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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 10-K
         (Mark One)
(X)  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
     ACT OF 1934

         For the fiscal year ended      December 31, 1996
                                        -----------------

( )  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
     EXCHANGE ACT OF 1934 

         For the transition period from__________________ to___________________


                         Commission File Number         0-19034

                         REGENERON PHARMACEUTICALS, INC.
             (Exact name of registrant as specified in its charter)

             New York                                13-3444607
             --------                                ----------
(State or other jurisdiction of         (I.R.S. Employer Identification No)
incorporation or organization)

777 Old Saw Mill River Road, Tarrytown, New York                  10591-6707
- ------------------------------------------------                  ----------
(Address of principal executive offices)                          (Zip code)

                                 (914) 347-7000
                                 --------------
              (Registrant's telephone number, including area code)

           Securities registered pursuant to Section 12(b) of the Act:

                                      None
                       -----------------------------------
                                (Title of Class)

                 Securities registered pursuant to Section 12(g)
                                  of the Act:

                    Common Stock - par value $.001 per share
                    ----------------------------------------
                                (Title of Class)

            Preferred Share Purchase Rights expiring October 18, 2006
            ---------------------------------------------------------
                                (Title of Class)

Indicate by check mark whether the registrant (1) has filed all reports required

to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. Yes x  No
                                      ---   ---

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K (ss.229.405 of this chapter) is not contained herein, and will
not be contained, to the best of registrant's knowledge, in definitive proxy or
information statements incorporated by reference in Part III of this Form 10-K
or any amendment to this Form 10-K. 
                                    ---
                                   
At March 11, 1997, the aggregate market value of voting stock held by
non-affiliates of the Registrant totaled approximately $194,810,771, based on
the last sale price as reported by The Nasdaq Stock Market.

Indicate the number of shares outstanding of each of Registrant's classes of
common stock as of March 11, 1997:

  Class of Common Stock                                  Number of Shares
  ------------------------------                         ----------------
  Class A Stock, $.001 par value                             4,355,994
  Common Stock, $.001 par value                             21,342,449


                      DOCUMENTS INCORPORATED BY REFERENCE:
     The Registrant's  definitive proxy statement to be filed in connection with
solicitation  of proxies for its Annual  Meeting of  Shareholders  to be held on
June 27, 1997  is  incorporated  by reference  into Part III of this Form 10-K.
Exhibit index is located on pages 32 to 34 of this filing.


                                       

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                                    PART I


Item 1.  Business

General

     Regeneron Pharmaceuticals, Inc. ("Regeneron" or the "Company") is a leader
in the application of molecular and cell biology to discover novel potential
therapeutics for human medical conditions and is seeking to develop and
commercialize these discoveries. The Company is applying its technological
expertise in protein growth factors, their receptors, and their mechanisms of
action to the discovery and development of drugs. The Company is pursuing
research programs in the following areas: (i) neurotrophic factors, including
brain-derived neurotrophic factor ("BDNF"), neurotrophin-3 ("NT-3"), and
AXOKINE(TM), for the treatment of neurological and retinal diseases and
conditions, (ii) the Angiopoietins, a new family of ligands (and their
receptors, called the TIE family of receptors) that appears to regulate blood
vessel formation, or angiogenesis, and may have a role in the production and

proliferation of blood cells (a process called hemopoiesis), (iii) muscle
atrophy, based on a receptor of the tyrosine kinase type that is specifically
expressed in skeletal muscle (called MuSK) and a protein ligand (agrin) for this
receptor, (iv) Noggin, a naturally occurring protein, for potential use in
treating abnormal bone formation and related diseases and conditions, and (v)
protein antagonists for cytokines such as interleukin-6 ("IL-6") as potential
treatment for inflammatory diseases, allergic disorders, and cancer.

     During 1996, Amgen Inc. ("Amgen"), on behalf of Amgen-Regeneron Partners (a
general partnership equally owned by Regeneron and Amgen), completed the
treatment phase of a Phase III clinical trial designed to determine the safety
and efficacy of BDNF delivered subcutaneously for the treatment of amyotrophic
lateral sclerosis ("ALS," commonly known as Lou Gehrig's disease). BDNF failed
to achieve its primary end points in that trial. See "Recent Development,"
below. In addition, in 1996, Amgen, on behalf of Amgen-Regeneron Partners,
continued to conduct a Phase I/II clinical trial of NT-3 for the treatment of
peripheral neuropathy caused by diabetes. Amgen also continued to conduct a
Phase I/II clinical trial of BDNF in Europe for the treatment of neuropathy
caused by diabetes and a Phase I/II trial for the treatment of Guillain-Barre
syndrome, and started a Phase I clinical trial in the United States and Europe
of BDNF delivered intrathecally for the treatment of ALS. The Company continued
in 1996 to develop and manufacture BDNF for use by Sumitomo Pharmaceuticals
Company, Ltd. ("Sumitomo Pharmaceuticals") in Japan and continued preclinical
research programs in the areas of angiogenesis, hematopoiesis, inflammatory and
muscle disease, abnormal bone formation and related disorders, and cancer (among
other programs). The Company is also engaged in a variety of research and
preclinical development activities relating to other neurotrophic and growth
factors, second generation neurotrophic factors (including chimeras), and other
novel potential therapeutics.

     In April 1996, Amgen purchased from the Company three million shares of
Common Stock for $48.0 million. The purchase price also included five-year
warrants to purchase an additional 700,000 shares of Common Stock at an exercise
price of $16.00 per share.

     In June 1996, the Company entered into a worldwide exclusive joint
development agreement with Medtronic, Inc. ("Medtronic") to collaborate on
research and development of a family of therapeutics for central nervous system
diseases and disorders using experimental Regeneron compounds and Medtronic
delivery systems. The initial target of the Medtronic collaboration will be the
development of Regeneron's second

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generation neurotrophic factor, AXOKINE(TM) for the potential treatment of
Huntington's disease, using Medtronic's implantable pump or other delivery
system to infuse or otherwise directly deliver AXOKINE into the brain. In
addition, Medtronic purchased from the Company 460,500 shares of Common Stock
for $10.0 million. The purchase price included five-year warrants to purchase an
additional 107,400 shares of Common Stock at an exercise price of $21.72 per
share.


     In August 1996, the Company entered into a collaboration agreement with
Pharmacopeia, Inc. ("Pharmacopeia"), a leader in the use of combinatorial
chemistry to discover potential small molecule, orally active pharmaceutical
product candidates, pursuant to which Regeneron and Pharmacopeia will conduct
research and development in a broad field of potential compounds and uses (the
"Pharmacopeia Agreement"). The Company also continued its research collaboration
with Glaxo-Wellcome plc ("Glaxo"), to pursue the discovery and development of
small molecule compounds that could potentially act as mimics, agonists, or
antagonists of neurotrophins (the "Glaxo Agreement").

     In December 1996, the Company entered into a collaboration agreement with
Procter & Gamble Pharmaceuticals, Inc. ("Procter & Gamble") seeking to 
discover and develop protein and small molecule compounds useful to treat
skeletal muscle disease and injury (the "Procter & Gamble Agreement"). Procter &
Gamble agreed to purchase $10.0 million of Regeneron Common Stock. Procter &
Gamble paid the $10.0 million to Regeneron in December 1996. In March 1997, the
price per share was set at $12.50 based on a 27 percent premium over an average
market price and Regeneron issued 800,000 shares of restricted Common Stock to
Procter & Gamble. In addition, Procter & Gamble will make a minimum of three and
up to five $3.75 million annual payments to Regeneron to support collaborative
muscle research.

     The Company has not received revenue from the sale of any commercial
product and has incurred losses in each year since inception of operations in
1988. As of December 31, 1996, the Company had an accumulated deficit of $157.0
million. To date, the Company has received revenues as compensation for research
and development efforts performed by Regeneron from its licensees and
collaborators, for contract manufacturing from Merck & Co., Inc. ("Merck"), and
investment income. There can be no assurance that such revenue will continue or
to what extent, if any, the Company's expenses incurred in connection with its
work on BDNF or NT-3 or other programs will be reimbursed by its licensees or
collaborators. In the absence of revenues from commercial product sales or other
sources (the amount, timing, nature, or source of which can not be predicted),
the Company's losses will continue as the Company conducts its research and
development activities. The Company's activities may expand over time and may
require additional resources, and the Company's operating losses may be
substantial over at least the next several years. The Company's losses may
fluctuate from quarter to quarter and will depend, among other factors, on the
timing of certain expenses and on the progress of the Company's research and
development efforts. There can be no assurance that the Company will ever have
an approved product or achieve significant revenues or profitable operations. To
date, Regeneron has not received any revenues from the commercial sale of
products and does not expect to receive any such revenues for at least several
years.

     The Company has incurred negative cash flow from operations in each year
since its inception. The Company expects that the funding requirements for its
activities will remain substantial and could increase significantly if, among
other things, its development or clinical trial programs are successful or its
research is expanded. In addition, the Company is required to provide capital
from time to time to fund and remain




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equal partners with Amgen in Amgen-Regeneron Partners. The Company's aggregate
capital contribution to Amgen-Regeneron Partners from the partnership's
inception in June 1993 through December 31, 1996 was $42.6 million. The Company
expects that its capital contributions in 1997 will total approximately $3.0
million to $5.0 million. These contributions could increase or decrease,
depending upon (among other things) the results of preclinical and clinical
studies of BDNF and NT-3. Capital contributions beyond 1997 are also anticipated
to be significant. In addition, the amount needed to fund the Company's
operations will also depend on other factors, including the potential future
need to expand the Company's professional and support staff and facilities to
support new areas of research and development, competitive products, the success
of the Company's research and development programs, the status of patent and
other intellectual property right developments, and the extent and success of
any collaborative research arrangements. The Company believes that its existing
capital resources will enable it to meet operating needs into 1999. No assurance
can be given that there will be no change in projected revenues or expenses that
would lead to the Company's capital being consumed significantly before such
time.

     Most drug research and development programs fail. A small minority of all
research and development programs ultimately result in commercially successful
drugs; it is not possible to predict whether any program will succeed until it
actually produces a drug that is commercially marketed for a significant period
of time. The Company is attempting to develop drugs for human therapeutic use
and no assurance can be made that any of the Company's research and development
activities will be successful or that any of the Company's current or future
potential product candidates will be commercialized.

Recent Development

     In January 1997, Amgen and Regeneron announced that the Phase III clinical
trial of BDNF delivered subcutaneously did not demonstrate clinical efficacy in
patients with ALS, that no further subsequent subcutaneous development of BDNF
for ALS was planned, and that the trial confirmed the safety and tolerability of
BDNF seen in earlier trials. The failure of the Phase III trial to achieve its
primary end points had a materially adverse effect on the price of the Company's
Common Stock (which declined more than 50% immediately after the announcement of
the results of the trial). After the Phase III clinical trial results were
announced, the Company retained independent experts in the fields of neurology
and gastroenterology, as well as independent statisticians, to conduct further
examination of the data. This review by the Company and the outside panels
indicated 1) that a subset of ALS patients in the trial may have received a
benefit from BDNF treatment and 2) that BDNF appeared to have an effect on the
gastrointestinal system and might have a therapeutic role in treating
constipating conditions, among other disorders. The panels recommended, among
other things, that additional clinical and preclinical investigations of
subcutaneous BDNF for ALS and BDNF for gastrointestinal conditions should be
undertaken. The Company is reviewing these recommendations and the Phase III
data and is discussing with Amgen and Sumitomo Pharmaceuticals whether to

undertake these or other investigations of BDNF. Further development of BDNF in
the United States must be undertaken in accordance with the terms of the
Company's collaboration agreement with Amgen. Although Sumitomo Pharmaceuticals
had planned a Phase I safety assessment of BDNF early in 1997, they are
currently reviewing their BDNF development plan in light of the recently
available information.




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The Company's Programs

     Neurotrophic Factors

     General. Neurodegenerative diseases are presently incurable conditions in
which there is a progressive loss of neurons that are crucial for functions such
as learning and memory, sensation (e.g., vision), control of movement, muscle
strength, and coordination. Neurodegenerative disorders are generally of unknown
cause. Symptoms often consist of progressive loss of memory, muscle control, or
sensation. Most of these diseases cause progressive functional diseases and may
cause permanent discomfort or disability. Regeneron's therapeutic strategy is to
use specific, naturally occurring proteins found in the human body --
neurotrophic factors -- to prevent degeneration or to promote regeneration of
specific populations of neurons.

 
    Part of Regeneron's research and development programs are directed first at
identifying neurotrophic proteins that have the capacity to arrest nerve
degeneration or restore nerve function. These proteins are then synthesized
principally by means of recombinant DNA technology. Preclinical studies of
certain of Regeneron's product candidates, including BDNF, NT-3, and AXOKINE,
suggest that these substances or their derivatives have potential therapeutic
value for a variety of neurological diseases and nerve injury or trauma.
Finally, the Company and Glaxo are conducting research to attempt to find small
molecules that might act to promote or affect neurotrophin activity that could
have a pharmaceutical role and that might be able to cross the blood-brain
barrier.

     BDNF. Brain-derived neurotrophic factor is a naturally occurring human
protein. Several biological properties of BDNF have been discovered. These
include the capacity of very small amounts of this protein to promote the
survival and differentiation of certain sensory neurons, motor neurons, nerve
cells of the retina, and several clinically important neurons in the brain.

     Preclinical studies suggest the potential clinical application of BDNF to a
variety of conditions in addition to ALS where motor neuron dysfunction is
present. These conditions could include motor neuron dysfunction that occurs in
Guillain-Barre syndrome, childhood spinal muscle atrophies, post-polio syndrome,
diabetic neuropathy, nerve trauma, and hereditary neuropathies. Amgen-Regeneron
Partners is continuing to conduct preclinical studies designed to support the
potential application of BDNF to certain of these conditions.


     During 1995 and 1996, Amgen conducted, on behalf of Amgen-Regeneron
Partners, a Phase III BDNF clinical trial to treat ALS. This study involved
1,135 patients, with each patient scheduled to receive subcutaneous treatment
for nine months. ALS is a disease that attacks motor neurons, those nerve cells
that cause muscles to contract. Degeneration of these neurons causes muscle
weakness, leading to death due to respiratory insufficiency. ALS afflicts adults
primarily between the ages of 40 and 70 years old; average survival is three to
five years following diagnosis. It is estimated that approximately 25,000 people
in the United States have ALS. In January 1997, the Company and Amgen announced
that the Phase III study failed to demonstrate clinical efficacy. The data
generated during the Phase III study are being analyzed by Regeneron which is in
discussions with Amgen and Sumitomo regarding what, if any, additional clinical
trials should be conducted with BDNF delivered subcutaneously for ALS or other
diseases or conditions (see "Recent Development"). Amgen and Amgen-Regeneron
Partners are conducting several early stage BDNF clinical trials for ALS
(delivered intrathecally), and peripheral neuropathy.



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     The Company and Amgen are conducting a Phase I trial of BDNF for ALS using
intrathecal delivery. While intrathecal delivery may be more successful in
delivering BDNF to certain motor neurons, it is not known whether intrathecal
delivery will prove any more successful in demonstrating safety and utility in
patients with ALS than the subcutaneous delivery used in the Phase III clinical
trial that failed to achieve its primary end points. In addition, the potential
success of any current or future BDNF clinical trial for the treatment of ALS
will be dependent upon, among other things, certain factors that could undermine
the significance of the data collected from such patients. Patients who take
Rilutek, an orally administered drug marketed by Rhone-Poulenc Rorer for the
treatment of ALS, might enroll in a BDNF trial. Other medications for the
treatment of ALS are available on an experimental basis and may be approved for
marketing in the future. The clinical effects of taking BDNF in combination with
other drugs is unknown and therefore unanticipated effects could complicate a
BDNF clinical trial or render the data collected difficult to analyze or
interpret. The design of any BDNF clinical trial will attempt to take into
account the inclusion of patients who may be taking other medications, including
Rilutek. However, if a clinical study is compromised through the inclusion of
patients who were taking Rilutek or other medications, with or without the
consent or knowledge of the trial sponsor, the results of the study may be
undermined and additional clinical studies may be required, causing a delay in,
and increasing the costs of, the development of BDNF, which would have a
material adverse effect on the Company. If additional studies of BDNF for ALS
are undertaken, the time and expense required for such trials could be material
to the Company and the outcome will be uncertain. If subsequent trials are
conducted and such trials fail to demonstrate that BDNF is safe and effective in
the treatment of ALS, that failure could have a materially adverse effect on the
Company, the price of the Company's Common Stock, and the Company's ability to
raise additional capital.

     NT-3. Neurotrophin-3 was the third member of the neurotrophin family
identified. Preclinical data suggest that NT-3 may be developed as a potential

therapeutic agent in the treatment of peripheral neuropathies, trauma to
peripheral nerves and spinal cord, and potentially other neurological disorders.
The therapeutic utility of certain drugs (in particular certain anticancer
agents such as cisplatin, taxol, and vincristine) is limited by the induction of
peripheral neuropathy. In animal models, NT-3 has been shown to reverse the
neuron damage caused by the cancer chemotherapeutic agent cisplatin.

     In the first clinical study measuring the safety and toxicity of NT-3,
conducted by Amgen on behalf of Amgen-Regeneron Partners, NT-3 was administered
by daily subcutaneous injection for seven days, over a wide range of doses, to a
limited number of normal human volunteers. A further clinical study of NT-3 as a
potential treatment for peripheral neuropathies caused by diabetes was started
during the first quarter of 1996 and continued into 1997. An additional trial
for peripheral neuropathies is planned to start in 1997; the decision whether
and when to start that clinical trial will now await Amgen-Regeneron Partners' 
review of the data from the diabetic neuropathy clinical trial. Amgen and
Regeneron are developing NT-3 in the United States under a license from Takeda
Chemical Industries, Ltd. ("Takeda").

     AXOKINE(TM). AXOKINE is Regeneron's second-generation neurotrophic factor,
discovered based on the Company's work with ciliary neurotrophic factor
("CNTF"). Preclinical data indicate that AXOKINE may be useful as a potential
therapeutic agent in the treatment of motor neuron disease, Huntington's and
other central nervous system degenerative diseases, and retinal degeneration
(including macular degeneration and retinitis pigmentosa). Preclinical data also
indicate that AXOKINE could have therapeutic and pharmacokinetic properties
superior to CNTF. Regeneron in 



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collaboration with Medtronic is developing AXOKINE for delivery via infusion or
injection to the central nervous system. Regeneron is also developing AXOKINE
for retinal degeneration and injury as well as other indications.

     Over the last few years, Regeneron has leveraged the proprietary
technologies and approaches it initially developed for the discovery and
characterization of neurotrophic factors to new growth factor-related areas. As
a result, the Company has substantially expanded its drug discovery and drug
development strategies, and is no longer primarily focused on neurological
diseases. Promising new areas, described below, include programs in angiogenesis
and the regulation of blood vessel growth, prevention of muscle atrophy, the
regulation of bone growth, and cytokines and the regulation of immune function.
Strategies involve both the discovery and development of recombinant
protein-based therapeutics and the discovery and development of small molecule
drugs.

     Angiogenesis and Hemopoiesis

     A plentiful blood supply is required to nourish every tissue and organ of
the body. Diseases such as diabetes and atherosclerosis wreck their havoc, in

part, by damaging the blood vessels (arteries, veins, and capillaries). The
decreased blood flow that results from such diseases can result in non-healing
skin ulcers and gangrene, painful limbs that cannot tolerate exercise, loss of
vision, and heart attacks. Building new blood vessels is a process known as
angiogenesis. Angiogenesis is required for normal growth and development and may
be limiting in tissue repair or ischemic states. Thus, new blood vessels are
required for tissue repair, and enhancement of blood vessel growth may aid in
improving circulation to ischemic limbs and heart tissue suffering from
atherosclerotic disease, in healing of skin ulcers or other chronic wounds, and
in establishing tissue grafts. Angiogenesis is also aberrantly involved in many
disease processes. Abnormal blood vessel growth is required for the growth and
metastasis of tumors, can lead to blindness when it occurs in and obscures the
retina, and seems to accompany an assortment of inflammatory processes.
Depending on the clinical situation, positively or negatively regulating blood
vessel growth could have important therapeutic benefits.

     Regeneron and others have identified a new family of receptors in the
tyrosine kinase class that appear critical for normal blood vessel formation and
perhaps abnormal vascularization as well. Through its ligand discovery program,
Regeneron has cloned and received patents for a new family of naturally
occurring protein ligands, collectively termed the "Angiopoietins," specific to
these blood vessel receptors. The Angiopoietins include naturally occurring
positive and negative regulators of angiogenesis, as described in significant
scientific manuscripts published within the last year. The Angiopoietin program
is in the early stage of discovery research, currently focusing on defining
potential clinical applications of this family of receptors and their ligands
and their applicability to either enhance or block blood vessel growth. Another
factor long known to act specifically on blood vessels, vascular endothelial
growth factor ("VEGF"), is undergoing extensive characterization for its
clinical potential at other companies and at many academic institutions and may
be competitive or synergistic to Regeneron's ligands.

     The receptors for the Angiopoietins are also expressed on early hemopoietic
stem cells. Thus, these factors may also be important in regulating blood cell
formation by the process known as hemopoiesis. Other hemopoietic growth factors
have proven useful in generating different types of blood cells in clinical
settings -- such as cancer chemotherapy -- when deficits of red blood cells,
white blood cells, and platelets can occur. These actions of the Angiopoietins
are also being examined.




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     Muscle Atrophy and Related Disorders

     Muscle atrophy occurs in many neuromuscular diseases and also when muscle
is unused, as often occurs during prolonged hospital stays and during
convalescence. Currently, physicians have few options to prescribe for patients
with muscle atrophy or other muscle conditions which afflict millions of
patients globally. Thus, a factor that might have beneficial effects on skeletal
muscle could have significant clinical benefit. The Company has identified a

receptor of the tyrosine kinase type termed MuSK that is specifically expressed
in skeletal muscle. This receptor is dramatically increased upon muscle injury
or disuse. A naturally occurring protein ligand for this receptor, termed agrin,
has also been identified at Regeneron. The muscle program is currently focused
on conducting in vivo and in vitro experiments with the objective of
demonstrating and further understanding the role of the muscle-specific receptor
and the activities of its ligand. Recent studies have revealed that this
receptor/ligand pair is absolutely required for the normal formation of the
connection between nerves and muscle. This work by Regeneron scientists gained
attention and formed the basis of the recent collaborative venture between the
Company and Procter & Gamble. This collaboration will explore the potential of
agrin and MuSK in muscle disease and also attempt to identify new orally active,
small-molecule drug candidates in this therapeutic arena by leveraging the
molecular expertise of the Company with the complementary expertise in chemical
libraries and high-throughput screening of Procter & Gamble.

     Abnormal Bone Growth and Related Disorders

     In collaboration with scientists at the University of California (San
Francisco), the Company has discovered human proteins that are natural
inhibitors of the proteins that regulate bone formation, known as the bone
morphogenic proteins ("BMPs"). The first such natural regulator, termed
"Noggin," is the most potent antagonist of BMP function yet described. In
addition to their apparent roles in normal bone formation, the BMPs also appear
to be involved in disease situations in which they promote abnormal bone growth.
One particularly devastating example is provided by the very rare disease known
as Fibrodysplasia Ossificans Progressiva ("FOP"), in which patients grow an
abnormal "second skeleton" that essentially locks them in place, preventing any
movement. As reported in the New England Journal of Medicine, BMPs appear to
play a causative role in this disease. Since Noggin is a potent blocker of the
BMPs implicated in FOP, it offers hope as a therapeutic agent in this
devastating disease. In addition, there are other less devastating but far more
common situations in which BMPs may be causing pathological bone growth and in
which Noggin or other negative regulators may be therapeutically useful. This
includes hip replacement surgery where abnormal bone growth can ruin the
surgical outcome.

     In addition, the Company is working to discover and develop antagonists of
Noggin, which may in some settings allow for promotion of BMP function, but only
where the BMP is normally being blocked by Noggin, to promote bone growth.

     The Company's research concerning regulators of bone growth includes
molecular and cellular research to improve or modify the Company's existing
regulators, process development efforts to produce experimental quantities of
these agents, and early stage in vivo and in vitro studies to further understand
and demonstrate the efficacy of the agents. The Company is also attempting to
discover more such regulators.




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     Cytokine Agonists and Antagonists

     Regeneron's widely-cited research on the CNTF class of neurotrophic factors
led to the discovery that CNTF, although it is a neurotrophic factor, belongs to
the "superfamily" of factors referred to as cytokines. This superfamily includes
factors such as erythropoietin, thrombopoietin, granulocyte-colony stimulating
factor, and the interleukins ("ILs"). Research at Regeneron has led to
proprietary insights into the receptors and signal transduction mechanisms used
by the entire cytokine superfamily and to novel approaches to develop both
agonists and antagonists for a variety of cytokines. Regeneron's scientists have
created protein-based antagonists for IL-1, IL-4, and IL-6 that are more potent
than previously described antagonists, allowing lower levels of these
antagonists to be used; moreover, these antagonists are comprised entirely of
natural human-derived sequences, and thus would not be expected to induce an
immune reaction in humans (although no assurance can be given since none have
yet been tested in humans). These cytokine antagonists are termed ligand traps.
Because pathological levels of IL-1, IL-4, and IL-6 seem to contribute to a
variety of disease states, these ligand traps have the potential to be important
therapeutic agents. Antagonists for IL-4 may be therapeutically useful in an
assortment of allergy and asthma-related disease situations in which IL-4 is
thought to play a contributory role and in a variety of vaccination settings in
which blocking IL-4 may help elicit more of the desired type of immune response
to the vaccine. Both IL-1 and IL-6 are referred to as pro-inflammatory cytokines
and have been implicated in the pathophysiology of a wide variety of human
disease conditions ranging from inflammatory disorders, such as rheumatoid
arthritis and sepsis, to cachexia (wasting). IL-6, in particular, is also
implicated in the pathology and progression of multiple myeloma, certain solid
tumors, AIDS, lymphomas (both AIDS-related and non-AIDS-related), osteoporosis,
and other conditions.

     The Company's research regarding protein-based cytokine antagonists
currently includes molecular and cellular research to improve or modify the
Company's ligand trap technology, process development efforts to produce
experimental quantities of the ligand traps, and early stage in vivo and in
vitro studies to further understand and demonstrate the efficacy of the ligand
traps. The Company is also developing similar high-affinity antagonists to other
cytokines.

     The Company has also entered into a substantial collaborative effort with
Pharmacopeia to use the Company's proprietary technology and insights concerning
cytokine receptors and their signaling, together with the proprietary
combinatorial- chemistry based small molecule libraries and high-throughput
screening technology provided by Pharmacopeia, for the discovery of small
molecule agonists and antagonists of a variety of members of the cytokine
superfamily. The objective of these collaborative efforts is to discover small
molecule mimics of protein therapeutics such as erythropoietin or
granulocyte-colony stimulating factor, as well as to discover small molecule
antagonists of interleukins such as IL-1, IL-4, and IL-6.

     Other Programs

     Orphan Receptor and Growth Factor Research. The therapeutic utility of many
growth factors depends, in part, on the exquisite specificity of their actions.
This specificity is determined largely by the limited distribution of receptors

for these factors on the target cells of interest. Using proprietary technology
initially developed for the discovery and characterization of neurotrophic
factors and their receptors, the Company has discovered new receptors and their
associated factors that act on particular cell 



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populations of potentially important clinical interest. These cell populations
include not only additional subsets of neurons but non-neuronal cells, such as
the endothelial cells that constitute blood vessels and skeletal muscle cells.
The Company's technology involves molecular biological as well as
"bioinformatics" approaches to identify and clone protein molecules that appear
to be receptors expressed on clinically relevant target cells for unknown
protein factors (hence their designation "orphan receptors"). The Company has
also obtained licenses and established collaborations for additional orphan
receptors, including licenses from the Salk Institute for Biological Studies.
The Company's technology includes approaches that allow for the identification
and molecular cloning of protein factors that bind to the orphan receptors.
Furthermore, the Company's technology allows for the development of derivatives
of the receptors and their factors, which can allow for modified agonistic or
antagonistic properties that may prove to be therapeutically useful.

     Other Research and Development. Regeneron has assembled scientists with a
variety of complementary skills and experience and operates its own facilities
to conduct a broad-based research, preclinical, and clinical development
program. Substantially all of the Company's operating expenditures to date have
related to the discovery and development of drug product candidates and the
purchase and renovation of facilities and equipment to produce product
candidates. One focus of the Company's research is factors that control the
survival, optimal function, and regeneration of neurons. Specific areas of this
research have included neuronal cell culture, animal models for human
neurological disorders, molecular cloning and gene regulation, monoclonal
antibodies, protein purification and analysis, and high-level expression of
recombinant proteins. As Regeneron's scientific efforts lead to potentially
promising new directions, both outside of recombinant protein therapies (into
orally active, small molecule pharmaceuticals) and outside of treatments for
neurological and neurodegenerative conditions (into, for example, potential
programs in cancer, inflammation, and muscle disease), the Company will require
additional internal expertise or external collaborations in areas in which it
currently does not have substantial resources and personnel.

Research Collaboration and Licensing Agreements

     To augment its research programs, Regeneron has entered into a variety of
collaborative research agreements and sponsored research agreements with
researchers and universities.  Under these agreements, the Company typically
receives certain proprietary rights to inventions or discoveries that arise as a
result of the research.  In addition, the Company has entered into significant
collaborative agreements with Amgen to develop, manufacture, and market BDNF and
NT-3, with Glaxo to discover and develop small molecule-based treatments for
neurodegenerative diseases, with Sumitomo Pharmaceuticals to develop BDNF for

commercialization in Japan, with Procter & Gamble to discover, develop, and
market protein and small molecule-based therapies for skeletal muscle diseases
and injuries, with Pharmacopeia to discover, develop, and market small
molecule-based pharmaceuticals, and with Medtronic to develop and market AXOKINE
delivered via infusion directly to the central nervous system.

     Agreement With Amgen Inc. In August 1990, Regeneron and Amgen entered into
a collaboration agreement (the "Amgen Agreement") and Amgen agreed to provide
$25.0 million of product development funding for BDNF and NT-3 payable in five
annual installments. The final such payment was made by Amgen in the second
quarter of 1995. In conjunction with entering into the Amgen Agreement, Amgen
made a $15.0 million equity investment in the Company. From inception of the
Amgen Agreement through December 31, 1996, the Company received contract
research and development payments



                                       9

<PAGE>


totaling $39.6 million directly from Amgen or from Amgen-Regeneron Partners.
Amgen has also agreed to pay to the Company a total of $13.0 million of research
progress payments, $1.0 million of which was paid on the signing of the Amgen
Agreement, $1.0 million of which was paid in July 1993 on the filing by Amgen of
the IND application for BDNF, and $1.0 million of which was paid in September
1994 on the filing by Amgen of the IND application for NT-3. The remaining $10.0
million, which is divided equally between BDNF and NT-3, will be paid upon the
achievement of certain further milestones in respect of each compound. There 
can be no assurance that any additional research progress payments will be made.

     Under the Amgen Agreement, following preclinical development, Amgen and the
Company will attempt to develop and, if such effort is successful,
commercialize, market, and distribute BDNF and NT-3 drug products in the United
States through Amgen- Regeneron Partners. Amgen-Regeneron Partners is governed
by a six member Joint Management Committee composed of three members each from
Regeneron and Amgen. The Joint Management Committee determines annually, in
advance, the capital requirements for Amgen-Regeneron Partners and approves a
budget and product plan for each product under development. To maintain an equal
interest in Amgen-Regeneron Partners, Amgen and Regeneron are obligated to make
equal capital contributions to the partnership (such capital contributions
exclude Amgen's product development funding obligation described above). Such
capital contributions may be substantial. Amgen has the duty to direct and
conduct clinical trials of BDNF and NT-3 in the United States in accordance with
an annual product plan and budget that is approved by the Joint Management
Committee. Amgen is also responsible for the preparation of protocols with
respect to such trials. Amgen has the primary responsibility to develop
manufacturing processes for, and to manufacture, BDNF and NT-3 on behalf of
Amgen-Regeneron Partners. Assuming equal capital contributions to
Amgen-Regeneron Partners, Regeneron and Amgen share any profits or losses of
Amgen-Regeneron Partners equally.

     The development and commercialization of BDNF and NT-3 outside of the

United States, Japan, China, and certain other Pacific Rim countries will be
conducted solely by Amgen through a license from the Company and, with respect
to NT-3, from Takeda (under a license agreement between Amgen/Regeneron,
Genentech and Takeda). In return, the Company will receive royalty payments
based on Amgen's net sales of any products in the licensed territory. In the
licensed territory, Amgen is solely responsible for funding clinical development
and related costs of the licensed products, as well as costs of their commercial
exploitation, and will have sole discretion with respect to all such
development, manufacturing, and marketing of the products and sole
responsibility for filing applications for regulatory approvals.

     At the time it entered into the Amgen Agreement, Amgen agreed that until
the earlier of August 2010 or termination of the Amgen Agreement, it will not
take any steps or assist any third party to take steps to acquire control of the
Company, whether by acquisition of capital stock, proxy contest, tender offer,
merger, sale of assets, or voting agreements, except under certain
circumstances.

     Agreement With Glaxo-Wellcome plc. In July 1993, the Company and Glaxo
agreed to conduct collaborative research with the objective of identifying
neurotrophin- related small molecules that could be useful for the treatment of
neurological and psychiatric diseases, including central nervous system diseases
such as Alzheimer's disease and Parkinson's disease, neuropsychiatric diseases
and conditions such as pain, depression, and eye diseases. This research is
directed by a joint management committee comprised of three Glaxo and three
Regeneron appointees. The collaborative research focuses on utilizing a
molecular understanding of the mechanism of action of the 



                                       10

<PAGE>

neurotrophin family of neurotrophic factors as a basis for discovery of lead
compounds. In addition, the identification of genes involved in synapse
formation and the control of neuronal cell death in model systems will be
analyzed to identify lead compounds for drug development. If such lead compounds
are identified, Glaxo will have the authority to determine whether to conduct
exploratory development. Following exploratory preclinical and initial clinical
development, which will be funded by Glaxo, further clinical development will be
conducted under the direction of Glaxo and will be jointly funded by Glaxo and
the Company. Glaxo has also agreed to pay the Company certain milestone
payments, none of which have been paid. If Glaxo determines not to conduct
exploratory development and in certain other circumstances, Regeneron has
certain rights to obtain such compounds for its own development and
commercialization.

     Under the Glaxo Agreement, if the Company contributes equally with Glaxo to
the costs of the development effort described above, the Company will be
entitled to require that any resulting products be commercialized by one or more
joint ventures formed by Glaxo and Regeneron. The Company will have the right to
contribute up to 50% of the capital of each such joint venture. Glaxo will be
responsible for the manufacture and supply of products to each such joint
venture entity pursuant to an agreed upon transfer price formula and other terms

and conditions. Glaxo and Regeneron will receive payments from each such joint
venture based on their respective capital contributions and will receive equal
royalty payments based on net sales.

     In connection with the Glaxo Agreement, Glaxo purchased 500,000 shares of
Common Stock for $10.0 million. Glaxo also obtained certain piggyback
registration rights (exercisable after the collaboration terminates) and agreed
that until the earlier of July 1998 or the termination of the collaboration
agreement it will not take any steps or assist any third party to take steps to
acquire control of the Company, whether by acquisition of capital stock, proxy
contest, tender offer, merger, sale of assets, or voting agreements, except
under certain circumstances.

     Agreement With Sumitomo Pharmaceuticals Company, Ltd. In June 1994, the
Company and Sumitomo Pharmaceuticals entered into an agreement for the research,
development, and commercialization of BDNF in Japan. Under the terms of the
agreement, Sumitomo Pharmaceuticals will pay up to $40.0 million to Regeneron,
including up to $25.0 million in research payments (of which Regeneron has
received $22.0 million as of December 31, 1996) and up to $15.0 million in
progress payments payable upon achievement of certain development milestones. No
progress payments have been made to date. In addition, Sumitomo Pharmaceuticals
agreed to reimburse Regeneron for its activities in developing manufacturing
processes for BDNF and supplying BDNF and other research materials to Sumitomo
Pharmaceuticals. Such manufacturing revenue totaled $8.5 million in 1996, $7.0
million in 1995, and $3.1 million in 1994. The agreement may be terminated by
Sumitomo Pharmaceuticals at its discretion; such termination would result in the
reversion to Regeneron of all rights to BDNF in Japan.

     Agreement With Sumitomo Chemical Company, Limited. In connection with a
$4.4 million equity investment made by Sumitomo Chemical in March 1989, the
Company granted Sumitomo Chemical a limited right of first negotiation to
license up to three of the product candidates the Company decides to
commercialize in Japan on financial and commercial terms as may be offered by
the Company. The Company's collaborative agreement with Sumitomo
Pharmaceuticals, an affiliate of Sumitomo Chemical, to develop BDNF in Japan,
described above, is the first of such license agreements. In connection with its
equity investment, Sumitomo Chemical paid the Company an additional $5.6
million, representing a deposit for reimbursable costs and 



                                       11

<PAGE>

expenses in product research and development. All available technology
development contract revenue was recognized by the end of 1992. The Company is
obligated periodically to inform and, if requested, to meet with Sumitomo
Chemical management about its progress in research and development.

     Agreement with Medtronic, Inc. In June 1996, the Company entered into a
worldwide exclusive joint development agreement with Medtronic to collaborate on
the research and development of a family of therapeutics for central nervous
system diseases and disorders using experimental Regeneron compounds and
Medtronic delivery systems. The initial target of the Medtronic collaboration

will be the development of AXOKINE for the potential treatment of Huntington's
disease, using Medtronic's implantable pump or other delivery system to infuse
or otherwise directly deliver AXOKINE into the central nervous system. Under the
agreement, the Company will pay Medtronic defined royalties based on sales of
AXOKINE delivered to the central nervous system using a Medtronic delivery
device. In addition, Medtronic purchased from the Company 460,500 shares of
Common Stock for $10.0 million. The purchase price included five-year warrants
to purchase an additional 107,400 shares of Common Stock at an exercise price of
$21.72 per share. Medtronic also obtained certain piggyback registration rights
and agreed that until the later of the termination of the collaboration
agreement or five years from the date of the agreement, it will not take any
steps or assist any third party to take steps to acquire control of the Company,
whether by acquisition of capital stock, proxy contest, tender offer, merger,
sale of assets, or voting agreements, except under certain circumstances.

     Agreement With Pharmacopeia, Inc. In October 1996, Regeneron and
Pharmacopeia entered into an agreement to collaborate exclusively in a series of
research programs the objective of which is to discover novel small molecule,
orally active therapeutics that are agonists, antagonists, or mimics of a broad
range of cytokines and growth factors. Subject to the ability of either or both
parties to opt-out of such efforts, any potential product candidate that may
emerge from this joint research will be jointly developed by Regeneron and
Pharmacopeia, with each party sharing equally in the costs of such efforts and
in any profits that may derived from such potential products. The Pharmacopeia
Agreement provided for no financial payments by either party, subject to the
mutual obligation to use reasonable efforts to discover lead compounds for
future development.

     Agreement with Procter & Gamble Pharmaceuticals, Inc. In December 1996,
Procter & Gamble and Regeneron entered into an exclusive worldwide agreement to
discover and develop therapeutics for muscle diseases and disorders. Procter &
Gamble agreed to purchase shares of Regeneron Common Stock for $10.0 million and
make a minimum of three and up to five $3.75 million annual payments to
Regeneron to support collaborative muscle research. Procter & Gamble paid the
$10.0 million to Regeneron in December 1996. In March 1997, the price per share
was set at $12.50 based on a 27 percent premium over an average market price and
Regeneron issued 800,000 shares of restricted Common Stock to Procter & Gamble.
In addition, Procter & Gamble agreed to conduct muscle disease and disorder
research at its research facilities, and contribute the results of that effort
to the collaboration. Profits will be shared equally from any products jointly
developed and marketed. Procter & Gamble may terminate its research payment
obligation after three years, subject to reversion of certain rights to
Regeneron. Regeneron contributed its muscle technologies and intellectual
property, including its MuSK receptor and related technology, to the
collaboration. In addition to the potential development of protein-based
therapeutics, the collaboration will seek to 



                                       12

<PAGE>



discover and develop small molecule, orally active therapeutics useful in the
treatment of muscle diseases and conditions.

     Procter & Gamble also obtained certain piggyback registration rights
(exercisable after the collaboration terminates) and agreed that until the
earlier of December 2001 or the termination of the collaboration agreement it
will not take any steps or assist any third party to take steps to acquire
control of the Company, whether by acquisition of capital stock, proxy contest,
tender offer, merger, sale of assets, or voting agreements, except under certain
circumstances.

     Other Agreements. The Company also has agreements with individual
researchers and universities to conduct sponsored research and development
programs. The goal of such agreements is to extend the Company's capabilities
and to acquire proprietary rights to the results of sponsored research. The
Company is a party to a number of sponsored research agreements which include
grants to the Company of exclusive licenses to certain discoveries and
technologies developed at, among other places, the Max Planck Institute
(covering the field of neurotrophic factors, including work done at the Max
Planck Institute on BDNF, NT-3, and other substances), and the University of
California at San Francisco (covering the use of neurotrophic factors and other
recombinant proteins to treat degenerative conditions of the eye).

     In addition to these sponsored research agreements, the Company
(individually or in partnership with Amgen pursuant to the Amgen Agreement)
provides resource material and information that relate to its product candidates
and research programs to over 400 investigators at private and public
institutions throughout the world. Regeneron supplies materials and know-how to
these investigators on a confidential basis in exchange for access to additional
research and ownership of certain proprietary rights resulting from the work of
the investigators.

      There can be no assurance that any of these agreements will result in work
that will have commercial potential or other useful benefit to the Company, or,
that if any such work has useful benefit to the Company, the Company will be
able to protect its proprietary position adequately to realize any possible
commercial benefit.

Manufacturing

     The Company completed construction of its first manufacturing facility in
1992 in Tarrytown, New York. This facility, which was designed to comply with
FDA current good manufacturing practices ("GMP"), is intended to produce
preclinical and clinical supplies of compounds. Depending on the dosage of its
drugs, the facility could also produce either bulk compounds or the final dosage
form of certain product candidates.

     In 1993, the Company purchased its Rensselaer, New York manufacturing
facility, which is being used to produce BDNF for use by Sumitomo
Pharmaceuticals and will be used to produce vaccine intermediate material for
Merck. The Company may use the facility to produce other product candidates and
materials in the future.

     Among the conditions for regulatory marketing approval of a drug is the

requirement that the prospective manufacturer's quality control and
manufacturing procedures conform to the GMP regulations of the health authority.
In complying with standards set forth in these regulations, manufacturers must
continue to expend time, money, and effort in the area of production and quality
control to ensure full technical compliance. Manufacturing establishments, both
foreign and domestic, are also subject 



                                       13

<PAGE>


to inspections by or under the authority
of the FDA and by other federal, state, and local agencies.

Competition

     There is substantial competition in the biotechnology industry. Many of the
Company's competitors have substantially greater research, preclinical and
clinical product development, manufacturing capabilities, and financial,
marketing, and human resources than Regeneron. Smaller companies may also prove
to be significant competitors, particularly as a result of acquiring or
discovering patentable inventions or as a result of collaborative arrangements
with large pharmaceutical companies or their acquisition by large pharmaceutical
companies. The Company's agreements with larger, better established
pharmaceutical companies are intended to secure for the Company the benefits of
such a collaboration with a more experienced pharmaceutical firm. Technological
development and discoveries may require the Company to change its research and
development efforts to develop effective therapeutics. Competitors with greater
resources than the Company may have financial and technological flexibility to
respond to such needed changes that the Company does not have.

     Even if BDNF or NT-3 is shown to be safe and effective to treat ALS,
peripheral neuropathy, or other neurological conditions, other companies have
developed or are developing drugs for the treatment of the same or similar
conditions. For example, the FDA has approved the application of Rhone-Poulenc
Rorer to market riluzole (under the tradename Rilutek), an orally administered
drug, to treat ALS in the United States, and Rhone-Poulenc Rorer has filed
applications for, and gained approval in, other countries. More broadly,
Regeneron is engaged in an intensely competitive field. Amgen and the Company
are direct competitors in the field of neurotrophic factors and possibly other
fields. Other potential competitors include Genentech, Inc. ("Genentech") which
is developing NGF to treat peripheral neuropathies, is a co-licensee under the
Amgen/Regeneron NT-3 license with Takeda, and may be developing other
neurotrophic factors, and Cephalon, Inc. ("Cephalon"), which is developing, in
collaboration with Chiron Corporation, insulin-like growth factor ("IGF-1", also
known as Myotrophin(TM)) and other compounds for the treatment of ALS,
peripheral neuropathies, and other conditions. Amgen, Genentech, Cephalon, and
others have filed patent applications, obtained issued patents relating to
neurotrophic factors, or have announced that they are actively pursuing
preclinical or clinical development programs in the area of neurotrophic
factors. Cephalon has announced that, based on the results of its Phase III
clinical studies with IGF-1 to treat ALS, it has filed or intends to file

applications for approval to market IGF-1 to treat ALS in the United States and
other countries. Amgen and Genentech have separately also announced research and
development of glial cell-line derived neurotrophic factor ("GDNF") for the
treatment of ALS, Parkinson's disease, and other conditions. Other companies
have developed or are developing drugs based on technology other than
neurotrophic factors for the treatment of diseases and injuries relating to the
nervous system (including ALS). The Company is also aware that several
pharmaceutical companies are conducting clinical trials in ALS with drugs which,
like riluzole, are orally administered.

     If a competitor announces a successful clinical study involving a product
that may be competitive with one of the Company's product candidates or an
approval by a regulatory agency of the marketing of a competitive product, such
announcement may have a material adverse effect on the operations or future
prospects of the Company or the price of its Common Stock.




                                       14

<PAGE>

     A number of corporate and academic competitors are involved in the
discovery and development of novel therapeutics using tyrosine kinase receptors,
orphan receptors, and compounds that are the focus of other research programs
now being conducted by the Company. These competitors include Amgen, Genentech,
and others. Many firms are engaged in research and development in the areas of
cytokines, interleukins, angiogenesis, and muscle conditions. Every
pharmaceutical and many biotechnology companies are engaged in attempting to
discover and develop small-molecule based therapeutics, similar in at least
certain respects to Regeneron's programs with Glaxo, Pharmacopeia, and Procter &
Gamble. In these and related areas, intellectual property rights have been
sought and certain rights have been granted to competitors and potential
competitors of the Company, and the Company may be at a substantial competitive
disadvantage in such areas as a result of, among other things, the Company's
lack of experience, trained personnel, and expertise.

     The Company also competes with academic institutions, governmental
agencies, and other public or private research organizations which continue to
conduct research, seek patent protection, and establish collaborative
arrangements for the development and marketing of products that would provide
royalties for use of their technology. These institutions are becoming more
active in seeking patent protection and licensing arrangements to collect
royalties for use of the technology that they have developed. Products developed
in such a manner may compete directly with any products developed by the
Company. The Company also competes with others in acquiring technology from such
institutions, agencies, and organizations.

     The relative speed with which Regeneron can develop safe and effective
product candidates, complete clinical testing and approval processes, and supply
commercial quantities of the product to the market will have an important impact
on the Company's competitive position. Competition among product candidates
approved for sale may be based on efficacy, safety, reliability, availability,
price, patent position, and other factors.


Patents, Trademarks, and Trade Secrets

     The Company's success depends, in part, on its ability to obtain patents,
maintain trade secret protection, and operate without infringing on the
proprietary rights of third parties. The Company's policy is to file patent
applications to protect technology, inventions, and improvements that are
considered important to the development of its business. The Company has been
granted a number of U.S. patents and is the exclusive or nonexclusive licensee
of a number of additional U.S. patents and patent applications. The Company also
relies upon trade secrets, know-how, and continuing technological innovation to
develop and maintain its competitive position. The Company or its licensers or
collaborators have filed patent applications on products and processes relating
to neurotrophic factors and other technologies and inventions in the United
States and in certain foreign countries. The Company intends to file additional
patent applications, when appropriate, relating to improvements in its
technologies and other specific products and processes. The Company plans to
aggressively prosecute, enforce, and defend its patents and other proprietary
technology.

     The patent positions of biotechnology firms, including the Company, are
generally uncertain and involve complex legal and factual questions. No
predictions can be made regarding the breadth, validity, or enforceability of
claims allowed in these types of patents. The Company does not know whether any
of its pending applications will result in the issuance of any patents or if any
currently issued patents or any patents 



                                       15

<PAGE>

issued in the future will provide significant proprietary protection or will be
circumvented or invalidated or will infringe on the rights of others.

     Competitors have filed applications for, or have been issued, patents and
may obtain additional patents and proprietary rights related to products or
processes competitive with those of the Company. Accordingly, there can be no
assurance that the Company's patent applications will result in patents being
issued in addition to those described above or that, if issued, the patents will
afford protection against competitors with similar technology; nor can there be
any assurance that others will not obtain patents that the Company will need to
license or circumvent. The Company is aware that one patent has issued in the
United States and patent applications in certain foreign countries were filed by
Amgen and others for the production of neurotrophic factor proteins, and that a
U.S. patent has issued to Genentech on processes relating to NGF. The Company is
further aware that patent applications have been filed in the United States and
certain foreign countries by Takeda, Amgen, and, the Company believes,
Genentech, on products and processes relating to NT-3. The Company has received
a co-exclusive license to NT- 3 as a result of a worldwide licensing agreement
between Amgen/Regeneron, Takeda, and Genentech. In November 1994, Genentech was
issued a U.S. patent relating to the nucleic acids encoding NT-4/5 and methods
for its recombinant production. Other patent filings by these companies or
others may be competitive with the Company's patent claims or may cause, if

valid and issued in the United States or a foreign jurisdiction, substantial
commercial difficulties or additional expenses or delays to the Company's
operations or commercial activities or may require the Company to cease certain
development or commercial activities altogether. The Company cannot predict
whether its or its competitors' patent applications will result in valid patents
being issued.

     The Company is currently involved in two interference proceedings in the
United States Patent and Trademark Office between Regeneron's patent
applications and patents issued to Synergen, Inc. ("Synergen") relating to CNTF.
Amgen acquired all outstanding shares of Synergen in 1994. The Company incurred
$1.1 million for legal expenses relating to the interference proceedings through
December 31, 1996. Since April 1995, the Company has not incurred substantial
expenses in connection with these proceedings. Although the patent interference
proceedings have not involved substantive discovery or other adversarial
activities to date, future patent interference proceedings could result in
substantial legal fees and other costs. The final result of the proceedings
cannot be reasonably predicted.

Government Regulation

     Regulation by government authorities in the United States and foreign
countries is a significant factor in the research, development, manufacture, and
marketing of the Company's product candidates. All of the Company's product
candidates will require regulatory approval before they can be commercialized.
In particular, human therapeutic products are subject to rigorous preclinical
and clinical trials and other premarket approval requirements by the FDA and
foreign authorities. Many aspects of the structure and substance of the FDA and
foreign pharmaceutical regulatory practice have been reformed during recent
years, and continued reform is under consideration in a number of forums. The
ultimate outcome and impact of such reforms and potential reforms cannot be
reasonably predicted.

     Clinical trials are conducted in accordance with certain standards under
protocols that detail the objectives of the study, the parameters to be used to
monitor safety and the efficacy criteria to be evaluated. Each protocol must be
submitted to the FDA. 





                                       16

<PAGE>


The phases of clinical studies may overlap. The designation of a clinical trial
as being of a particular phase is not necessarily indicative that such a trial
will be sufficient to satisfy the parameters of a particular phase, and a
clinical trial may contain elements of more than one phase notwithstanding the
designation of the trial as being of a particular phase. No assurance can be
given that the results of preclinical studies or early stage clinical trials
will predict long-term safety or efficacy of the Company's compounds when they
are tested or used more broadly in humans. Various federal and state statutes

and regulations also govern or influence the research, manufacture, safety,
labeling, storage, recordkeeping, marketing, transport, or other aspects of such
products. The lengthy process of seeking these approvals and the compliance with
applicable statutes and regulations require the expenditure of substantial
resources. Any failure by the Company or its collaborators or licensees to
obtain, or any delay in obtaining, regulatory approvals could adversely affect
the marketing of any products developed by the Company and its ability to
receive product or royalty revenue.

     In addition to the foregoing, the Company's present and future business
will be subject to regulation under the United States Atomic Energy Act, the
Clean Air Act, the Clean Water Act, the Comprehensive Environmental Response,
Compensation and Liability Act, the National Environmental Policy Act, the Toxic
Substances Control Act, and the Resource Conservation and Recovery Act, national
restrictions, and other present and potential future local, state, federal, and
foreign regulations.

Employees

     As of December 31, 1996, the Company had 243 full-time employees, 48 of
whom hold a Ph.D. and/or M.D. degree. Of the full-time employees, 198 are
engaged in or directly support research and development. The Company believes
that it has been highly successful in attracting skilled and experienced
personnel; however, competition for such personnel is intense. None of the
Company's personnel are covered by collective bargaining agreements, and
management considers its relations with its employees to be good.


Item 2. Properties

     Regeneron conducts the Company's research, development, manufacturing, and
administrative activities at its own facilities. The Company currently leases
approximately 121,000 square feet of office, laboratory, and manufacturing space
in Tarrytown, New York. The current monthly base rental charge is $224,825, with
increases based upon increases in taxes and operating expenses. The lease for
this facility expires on June 30, 1998, subject to an option to renew the lease
for two additional five-year periods. The Company owns the Rensselaer facility,
consisting of two buildings totaling approximately 104,000 square feet of
research, manufacturing, office, and warehouse space.

     As the Company's activities expand, additional space may be required. In
the future, the Company may locate, lease, operate, or purchase additional
facilities in which to conduct expanded research and development activities and
manufacturing and commercial operations.



                                       17

<PAGE>



Item 3. Legal Proceedings

     Other than the patent interference proceedings which were declared by the
United States Patent and Trademark Office, the Company is not engaged in any

litigation or formal legal proceedings.


Item 4.  Submission of Matters to a Vote of Security Holders

     None.

Executive Officers of the Registrant

     Listed below are the executive officers of the Company as of March 11,
1997. There are no family relationships between any of the executive officers
and there is no arrangement or understanding between any executive officer and
any other person pursuant to which the executive officer was selected. At the
annual meeting of the Board of Directors, which follows the Annual Meeting of
Shareholders, executive officers are elected by the Board to hold office for one
year and until their respective successors are elected and qualified, or until
their earlier resignation or removal.

     Information with regard to the directors of the Company, including that of
the following executive officers who are directors, is incorporated by reference
to Regeneron Pharmaceuticals, Inc. Proxy Statement to be filed in connection
with solicitation of proxies for its Annual Meeting of Shareholders to be held
on June 27, 1997.

Name                                  Age              Position
- ----                                  ---              --------

Leonard S. Schleifer, M.D., Ph.D.     44    Chief Executive Officer, President,
                                            and founder of the Company

Murray A. Goldberg                    52    Vice President, Finance &
                                            Administration, Chief Financial
                                            Officer, and Treasurer

Paul Lubetkin                         46    Vice President, General Counsel,
                                            and Secretary

Ronald M. Lindsay, Ph.D.              49    Vice President, Neurobiology

George D. Yancopoulos, M.D., Ph.D.    37    Vice President, Discovery

Jesse M. Cedarbaum, M.D.              44    Vice President, Clinical Affairs

Randall G. Rupp, Ph.D.                49    Vice President, Manufacturing and
                                            Process Science

Gail M. Kempler, Ph.D.                42    Vice President, Intellectual
                                            Property and Associate General
                                            Counsel

Beverly C. Dubs                       42    Controller and Assistant Treasurer



                                       18


<PAGE>


                                    PART II


Item 5. Market for Registrant's Common Equity and Related Stockholder Matters

     The Common Stock of Regeneron is quoted on The Nasdaq Stock Market under
the symbol "REGN". The Company's Class A Common Stock, par value $.001 per
share, is not publicly quoted or traded.

     The following table sets forth, for the periods indicated, the range of
high and low bid quotations for the Common Stock as reported by The Nasdaq Stock
Market. The bid prices reflect inter-dealer quotations without retail mark-ups,
mark-downs, or commissions and do not necessarily represent actual transactions.

                                             High             Low
                                             ----             ---
1995
First Quarter ...........................    $ 7.00          $3.00
Second Quarter ..........................     10.00           5.50
Third Quarter ...........................     16.375          8.75
Fourth Quarter ..........................     15.625          8.625

1996
First Quarter ............................    16.625         11.375
Second Quarter ...........................    19.75          11.75
Third Quarter ............................    20.50          13.25
Fourth Quarter ...........................    24.50          14.875

     As of March 11, 1997, there were approximately 947 holders of record of the
Company's Common Stock and 91 holders of record of the Company's Class A Common
Stock. The closing bid price on that date was $8.75.

     The Company has never paid cash dividends on its common shares and does not
intend to pay cash dividends in the foreseeable future. In addition, under the
terms of certain debt and equipment lease financing agreements, the Company is
not permitted to declare or pay dividends to its shareholders.


                                       19

<PAGE>




Item 6.  Selected Financial Data

         The selected financial data set forth below for the years ended
December 31, 1996, 1995, and 1994 and at December 31, 1996 and 1995 are derived
from and should be read in conjunction with the audited financial statements of
the Company, including the notes thereto, included elsewhere in this report.
The selected financial data for the years ended December 31, 1993 and 1992 and
at December 31, 1994, 1993 and 1992 are derived from audited financial
statements of the Company not included in this report.


         The Company has never paid cash dividends on its common shares and
does not anticipate paying any in the foreseeable future. In addition, under
the terms of certain debt agreements, the Company is not permitted to declare
or pay dividends to its shareholders.


<TABLE>
<CAPTION>

                                                                              Year Ended December 31,
                                                      --------------------------------------------------------------
                                                            1996                1995                     1994       
                                                      ------------------  ------------------   ---------------------
<S>                                                   <C>                 <C>                   <C>           
Statement of Operations Data
Revenues
     Contract research and development                      $17,302,473         $23,247,002           $19,606,292   
     Investment income                                        4,360,065           2,997,180             2,585,465   
     Contract manufacturing                                   2,451,424           1,140,321
     Research progress payments                                                                         1,000,000   
     Technology development contract                                                                                

                                                      ------------------  ------------------   -------------------  
                                                             24,113,962          27,384,503            23,191,757   
                                                      ------------------  ------------------   -------------------  

Expenses
     Research and development                                28,268,798          23,310,088            30,874,437   
     Loss in Amgen-Regeneron Partners                        14,250,239          13,804,777             9,794,237   
     General and administrative                               5,879,975           5,764,397             7,529,136   
     Depreciation and amortization                            6,083,845           5,885,699             4,245,686   
     Contract manufacturing                                   1,115,259              72,059
     Interest                                                   939,624           1,204,757             1,403,001   
     Other                                                                          850,000
                                                      --------------------------------------   -------------------  
                                                             56,537,740          50,891,777            53,846,497   
                                                      --------------------------------------   -------------------  
Net loss                                                   ($32,423,778)       ($23,507,274)         ($30,654,740)  
                                                      ==================  ==================   ===================  
Net loss per share                                               ($1.33)             ($1.19)               ($1.62)  
                                                      ==================  ==================   ===================  

Weighted average number of Common and
     Class A shares outstanding                              24,463,516          19,768,446            18,866,993   
                                                      ==================  ==================   ===================  


<CAPTION>

                                                                               At December 31,
                                                      --------------------------------------------------------------
                                                            1996                1995                  1994          
                                                      ------------------  ------------------   ---------------------
<S>                                                   <C>                 <C>                  <C>            
Balance Sheet Data
Cash, cash equivalents
     and marketable securities                              $97,027,766         $59,622,010          $60,215,256    
Working capital                                              72,960,217          36,254,422           34,040,342    
Total assets                                                137,581,854          93,811,345           94,235,806    
Capital lease obligations and note payable,
     long-term portion                                        5,148,097           5,977,866            9,249,471    
Stockholders' equity                                        106,930,999          67,856,449           67,070,567    

<CAPTION>

                                                              Year Ended December 31,
                                                      -----------------------------------------
                                                                 1993                 1992
                                                      ------------------   --------------------
<S>                                                   <C>                  <C>       
Statement of Operations Data
Revenues
     Contract research and development                       $6,092,319           $5,000,000
     Investment income                                        3,463,902            4,982,668
     Contract manufacturing                           
     Research progress payments                               1,000,000
     Technology development contract                                               1,553,601

                                                      ------------------   ------------------
                                                             10,556,221           11,536,269
                                                      ------------------   ------------------

Expenses
     Research and development                                36,755,883           23,809,313
     Loss in Amgen-Regeneron Partners                         3,511,346
     General and administrative                               6,025,921            3,993,504
     Depreciation and amortization                            3,101,055            2,109,958
     Contract manufacturing                           
     Interest                                                 1,045,953              736,183
     Other                                            
                                                      ------------------   ------------------
                                                             50,440,158           30,648,958
                                                      ------------------   ------------------
Net loss                                                   ($39,883,937)        ($19,112,689)
                                                      ==================   ==================
Net loss per share                                               ($2.41)              ($1.24)
                                                      ==================   ==================

Weighted average number of Common and
     Class A shares outstanding                              16,569,288           15,352,798
                                                      ==================   ==================


 <CAPTION>
                                                                 At December 31,
                                                      ----------------------------------------
                                                               1993                 1992
                                                      -------------------   ------------------
<S>                                                       <C>                  <C>        
Balance Sheet Data
Cash, cash equivalents
     and marketable securities                            $88,281,194          $83,344,257
Working capital                                            78,738,906           80,108,844
Total assets                                              117,579,418           97,879,953
Capital lease obligations and note payable,
     long-term portion                                      5,911,876            5,818,291
Stockholders' equity                                       98,388,159           87,153,427
</TABLE>


                                       20

<PAGE>

Item 7. Management's  Discussion and Analysis of Financial Condition and Results
        of Operations

General

          Overview. The discussion below contains forward-looking statements
that involve risks and uncertainties relating to the future financial
performance of Regeneron Pharmaceuticals, Inc. ("Regeneron" or the
"Company") and actual events or results may differ materially. These statements
concern, among other things, the possible therapeutic applications of the
Company's product candidates and research programs, the timing and nature of 
the Company's clinical and research programs now underway or planned, a variety
of items described herein and in the footnotes to the Company's financial
statements (including the useful life of assets, the anticipated length of
agreements, and other matters), and the future uses of capital and financial
needs of the Company. These statements are made by the Company based on
management's current beliefs and judgment. In evaluating such statements,
stockholders and investors should specifically consider the various factors
identified under the caption "Factors That May Affect Future Operating Results"
which could cause actual results to differ materially from those indicated by
such forward-looking statements.

          Regeneron is a New York corporation founded in 1988. It is a leader in
the application of molecular and cell biology to discover novel potential
therapies for human medical conditions. The Company is applying its
technological expertise in protein growth factors, their receptors, and their
mechanisms of action to the discovery and development of neurotrophic factors
for the potential treatment of neurodegenerative disease, peripheral neuropathy,
and nerve injury. More recently, Regeneron has used its technological expertise
to attempt to identify treatments for diseases and conditions outside of the
nervous system, such as inflammatory and muscle disease, angiogenesis,
hematopoiesis, and cancer. In addition to conducting research and development
during 1993 through 1996, highlights of Regeneron's operations included:

o    During 1993, the Company completed Phase II clinical trials and commenced

     Phase III clinical trials in the United States of ciliary neurotrophic
     factor ("CNTF") to treat amyotrophic lateral sclerosis ("ALS," commonly
     known as Lou Gehrig's disease). In addition, in accordance with its
     collaboration agreement with Amgen Inc. ("Amgen"), Amgen initiated clinical
     trials of brain-derived neurotrophic factor ("BDNF"), on behalf of
     Amgen-Regeneron Partners, for the treatment of ALS. The Company also added
     and renovated laboratory and administrative space, including the Rensselaer
     facility. In 1993, the Company raised a total of approximately $51.0
     million, primarily from the sale of Common Stock to Glaxo-Wellcome plc
     ("Glaxo") and in a public offering.

o    During 1994, the Company discontinued its Phase III clinical study of CNTF
     to treat ALS and implemented a strategy to concentrate on its most
     promising product candidates and its discovery research efforts and to seek
     additional corporate partnerships and licensing agreements. Regeneron also
     reduced its workforce by approximately 25%, to approximately 200 employees,
     and incurred a charge of approximately $0.4 million in connection with
     costs associated with the reduction in force.

o    During 1995, Amgen, on behalf of Amgen-Regeneron Partners, began a Phase
     III clinical trial of BDNF for the treatment of ALS designed to determine
     the safety and efficacy of BDNF to treat ALS. Amgen and Regeneron also
     analyzed results from the Phase I clinical trial and planned a further
     clinical trial of neurotrophin-3 ("NT-3") for peripheral neuropathy. The 
     Company continued to develop and manufacture BDNF for use by Sumitomo 
     Pharmaceuticals Company, Ltd. ("Sumitomo Pharmaceuticals") in Japan. 
     During the second quarter of 1995, the Company announced preclinical 
     research discoveries by Regeneron scientists in the areas of cancer, 
     muscle disease, and angiogenesis. In the third quarter of 1995, the 
     Company entered into a long-term manufacturing agreement with Merck & 
     Co., Inc. (the "Merck Agreement") under which the Company will produce at 
     its Rensselaer, New York facility an intermediate for an existing Merck 
     pediatric vaccine. In the fourth quarter of 1995, the Company raised 
     $22.3 million in net proceeds from a public offering of Common Stock. The 
     Company settled a securities class action lawsuit against the Company and 
     two individuals. As part of the settlement, the Company issued 153,017 
     shares of Common Stock in January 1996.


                                       21

<PAGE>



o    During 1996, Amgen, on behalf of Amgen-Regeneron Partners, completed the
     treatment phase of the Phase III clinical trial designed to determine the
     safety and efficacy of BDNF delivered subcutaneously for the treatment of
     ALS. In addition, Amgen, on behalf of Amgen-Regeneron Partners, continued
     to conduct a Phase I/II clinical trial of NT-3 for the treatment of
     peripheral neuropathy caused by diabetes. Amgen also continued to conduct a
     Phase I/II clinical trial of BDNF in Europe for the treatment of neuropathy
     caused by diabetes and started a Phase I clinical trial of BDNF delivered
     intrathecally for the treatment of ALS. The Company continued to develop
     and manufacture BDNF for use by Sumitomo Pharmaceuticals in Japan and

     continued preclinical research programs in the areas of inflammatory and
     muscle disease, angiogenesis, hematopoiesis, and cancer. In April 1996,
     Amgen purchased from the Company three million shares of Common Stock for 
     $48.0 million. The purchase price also included five-year warrants to 
     purchase an additional 700,000 shares of Common Stock at an exercise 
     price of $16.00 per share. In June 1996, the Company entered into a 
     worldwide exclusive joint development agreement with Medtronic Inc. 
     ("Medtronic") to collaborate on research and development of a family of 
     therapeutics for central nervous system diseases and disorders using 
     experimental Regeneron compounds and Medtronic delivery systems. The 
     initial target of the Medtronic collaboration will be the development of 
     AXOKINE(Trademark) for the potential treatment of Huntington's disease, 
     using Medtronic's implantable pump to infuse AXOKINE into the central 
     nervous system. Medtronic purchased from the Company 460,500 shares of
     Common Stock for $10.0 million; the purchase price included five-year
     warrants to purchase an additional 107,400 shares of Common Stock at an
     exercise price of $21.72 per share. In October 1996, Regeneron entered into
     a research collaboration with Pharmacopeia, Inc. ("Pharmacopeia") to
     discover and develop small molecule drugs that mimic or antagonize growth
     factors or cytokines. In December 1996, the Company entered into an
     exclusive worldwide agreement with Procter & Gamble Pharmaceuticals, Inc. 
     ("Procter & Gamble") to discover and develop therapeutics for muscle
     diseases and disorders. Procter & Gamble agreed to purchase shares of
     Common Stock for $10.0 million and make a minimum of three and up to five
     $3.75 million annual payments to the Company to support collaborative
     muscle research. Procter & Gamble paid the $10.0 million to Regeneron in
     December 1996. In March 1997, the price per share was set at $12.50 based
     on a 27 percent premium over an average market price and Regeneron issued
     800,000 shares of restricted Common Stock to Procter & Gamble.

          In January 1997, Amgen and Regeneron announced that the Phase III
clinical trial of BDNF delivered subcutaneously did not demonstrate clinical
efficacy in patients with ALS, that no further subsequent subcutaneous
development of BDNF for ALS was planned, and that the trial confirmed the safety
and tolerability of BDNF seen in earlier trials. The failure of the Phase III
trial to achieve its primary end points had a materially adverse effect on the
price of the Company's Common Stock (which declined more than 50% immediately
after the announcement of the results of the trial). After the Phase III
clinical trial results were announced, the Company retained independent experts
in the fields of neurology and gastroenterology, as well as independent
statisticians, to conduct further examination of the data. This review by the
Company and the outside panels indicated 1) that a subset of ALS patients in the
trial may have received a benefit from BDNF treatment and 2) that BDNF appeared
to have an effect on the gastrointestinal system and might have a therapeutic
role in treating constipating conditions, among other disorders. The panels
recommended, among other things, that additional clinical and preclinical
investigations of subcutaneous BDNF for ALS and BDNF for gastrointestinal
conditions should be undertaken. The Company is reviewing these recommendations
and the Phase III data and is discussing with Amgen and Sumitomo Pharmaceuticals
whether


                                       22

<PAGE>


to undertake these or other investigations of BDNF. Further development of BDNF
in the United States must be undertaken in accordance with the terms of the
Company's collaboration agreement with Amgen. Although Sumitomo Pharmaceuticals
had planned a Phase I safety assessment of BDNF early in 1997, they are
currently reviewing their BDNF development plan in light of the recently
available information.

          The results of the Company's and its collaborators' past activities in
connection with the research and development of BDNF and NT-3 do not necessarily
predict the results or success of future activities including, but not limited
to, any additional preclinical or clinical studies of BDNF or NT-3. The Company
can not predict whether, when, or under what conditions BDNF or NT-3 will be
shown to be safe or effective to treat any human condition or be approved for
marketing by any regulatory agency. The delay or failure of current or future
studies to demonstrate the safety or efficacy of BDNF or NT-3 to treat human
conditions or to be approved for marketing would have a material adverse impact
on the Company.

          The Company and Amgen are conducting a Phase I trial of BDNF for ALS
using intrathecal delivery. While intrathecal delivery may be more successful in
delivering BDNF to certain motor neurons (the nerve cells that degenerate in
ALS), it is not known whether intrathecal delivery will prove any more
successful in demonstrating safety and utility in patients with ALS than the
subcutaneous delivery used in the Phase III clinical trial that failed to
achieve its primary end points. In addition, the potential success of any 
current or future BDNF clinical trial for the treatment of ALS will be 
dependent upon, among other things, certain factors that could undermine the 
significance of the data collected from such patients. For example, patients 
who take Rilutek(Trademark), an orally administered drug marketed by 
Rhone-Poulenc Rorer for the treatment of ALS, might enroll in a BDNF trial. 
Also, other medications for the treatment of ALS are available on an 
experimental basis and may be approved for marketing in the future. The 
clinical effects of taking BDNF in combination with other drugs is unknown and 
therefore unanticipated effects could complicate a BDNF clinical trial or 
render the data collected difficult to analyze or interpret. The design of any 
BDNF clinical trial will attempt to take into account the inclusion of patients
who may be taking other medications, including Rilutek. However, if a clinical 
study is compromised through the inclusion of patients who were taking Rilutek 
or other medications, with or without the consent or knowledge of the trial 
sponsor, the results of the study may be undermined and additional clinical 
studies may be required, causing a delay in, and increasing the costs of, the 
development of BDNF, which would have a material adverse effect on the Company.
If additional studies of BDNF for ALS are undertaken, the time and expense 
required for such trials could be material to the Company and the outcome will 
be uncertain. If subsequent trials are conducted and such trials fail to 
demonstrate that BDNF is safe and effective in the treatment of ALS, that 
failure could have a materially adverse effect on the Company, the price of 
the Company's Common Stock, and the Company's ability to raise additional 
capital.

          No assurance can be given that extended administration of NT-3 will be
safe or effective. The Phase I study of NT-3 in normal human volunteers that
concluded in 1995 was a short term (seven day) treatment study. The 1996 study

involves substantially longer treatment (six months or longer). In the Phase I
study, two out of the seventy-six patients developed significant abnormalities
in blood tests of their liver function. These laboratory abnormalities reversed
after cessation of treatment and were not associated with any other evidence of
liver dysfunction. Similar abnormalities have not been observed in preclinical
toxicology studies with NT-3. However, if such abnormalities were to occur in a
number of patients in subsequent trials, including the 1996 study, this result
could delay or preclude the further development of NT-3. The treatment of


                                       23

<PAGE>
peripheral neuropathy associated with cancer chemotherapy or diabetes may
present additional clinical trial risks in light of the complex and not wholly
understood mechanisms of action that lead to the neuropathies, the presence of
many other drugs to treat the underlying conditions, the potential difficulty of
achieving significant clinical endpoints, and other factors. No assurance can be
given that these or any other studies of NT-3 will be successful or that NT-3
will be commercialized.

          To date, Regeneron has not received any revenues from the commercial
sale of products and may not receive any such revenues for several years. Before
such revenues can be realized, the Company (or its collaborators) must overcome
a number of hurdles which include successfully completing its research and
development efforts and obtaining regulatory approval from the United States
Food and Drug Administration ("FDA") or regulatory authorities in other
countries. In addition, the biotechnology and pharmaceutical industries are
rapidly evolving and highly competitive, and new developments may render the
Company's products and technologies noncompetitive and obsolete.

          In the absence of revenues from commercial product sales or other
sources (the amount, timing, nature, or source of which can not be predicted),
the Company's losses will continue as the Company conducts its research and
development activities. The Company's activities may expand over time and may
require additional resources, and the Company's operating losses may be
substantial over at least the next several years. The Company's losses may
fluctuate from quarter to quarter and will depend, among other factors, on the
timing of certain expenses and on the progress of the Company's research and
development efforts.


Results of Operations

          Years Ended December 31, 1996 and 1995. The Company's total revenue
decreased to $24.1 million in 1996 from $27.4 in 1995. Contract research and
development revenue decreased to $17.3 million in 1996 from $23.2 million in
1995. Contract research and development revenue earned from Sumitomo
Pharmaceuticals decreased to $11.5 million in 1996 from $15.4 million in 1995.
Of the 1996 Sumitomo Pharmaceuticals revenue, $3.0 million was for contract
research and $8.5 million was reimbursement for developing manufacturing
processes for BDNF and supplying BDNF. Of the 1995 Sumitomo Pharmaceuticals
revenue, $8.4 million was for contract research (including $5.4 million related
to a non-recurring contract research payment), and $7.0 million was
reimbursement for developing manufacturing processes for BDNF and supplying

BDNF. Contract research and development revenue earned from Amgen and
Amgen-Regeneron Partners decreased to $5.8 million in 1996 from $7.8 million
1995. This reflects a decision by the partnership to focus more spending in 1996
on clinical trials and precommercial activities conducted by Amgen and less
spending on preclinical research conducted by Regeneron. During 1995, the
Company entered into the Merck Agreement. Contract manufacturing revenue in 1996
and 1995 related to this agreement aggregated $2.4 million and $1.1 million,
respectively. Investment income for 1996 increased to $4.4 million from $3.0
million in 1995, primarily due to increased levels of interest-bearing 
investments resulting from the sale by the Company of equity securities in a 
public offering in November 1995 and in private placements to Amgen, Medtronic, 
and Procter & Gamble in April, June, and December 1996, respectively.

          The Company's total operating expenses increased to $56.5 million in
1996 from $50.9 million in 1995. Research and development expense increased to
$28.3 million in 1996 from $23.3 million in 1995, primarily due to costs related
to the Company's

                                       24

<PAGE>


preclinical research programs, as well as the costs of increased activity in the
Company's Rensselaer, New York manufacturing facility related to the Company's
agreement with Sumitomo Pharmaceuticals. Loss in Amgen-Regeneron Partners
increased to $14.3 million in 1996 from $13.8 million in 1995, primarily due to
increased costs related to clinical trials and other activities conducted by
Amgen on behalf of the partnership. Research and development expenses, including
the loss in Amgen-Regeneron Partners, were approximately 75% of total operating
expenses in 1996, compared to 73% in 1995.

          General and administrative expense increased to $5.9 million in 1996
from $5.8 million in 1995 as expenses remained consistent year-to-year. Interest
expense decreased to $0.9 million in 1996 from $1.2 million in 1995, resulting
from the expiration of capital leases during 1995 and 1996. Contract
manufacturing of $1.1 million in 1996 were direct expenses related to contract
manufacturing for Merck. Other expenses of $0.9 million in 1995 related to 
recognition of the Company's contribution to the settlement of shareholder 
class action litigation.

          The Company's net loss in 1996 was $32.4 million, or $1.33 per share,
compared to a net loss of $23.5 million, or $1.19 per share, in 1995.

          Years Ended December 31, 1995 and 1994. The Company's total revenue
increased to $27.4 million in 1995 from $23.2 million in 1994. Contract research
and development revenue increased to $23.2 million in 1995 from $19.6 million in
1994. Contract research and development revenue earned from Sumitomo
Pharmaceuticals increased to $15.4 million in 1995 from $10.7 million in 1994.
Of the 1995 Sumitomo Pharmaceuticals revenue, $8.4 million was for contract
research and $7.0 million was reimbursement for developing manufacturing
processes for BDNF and supplying BDNF. Of the 1994 Sumitomo Pharmaceuticals
revenue, $7.6 million was for contract research (including $5.4 million related
to a non-recurring contract research payment), and $3.1 million was
reimbursement for developing manufacturing processes for BDNF and supplying

BDNF. Contract research and development revenue earned from Amgen and
Amgen-Regeneron Partners decreased to $7.8 million in 1995 from $8.9 million in
1994. This decrease was the result of the Company providing less research
support to the partnership. During 1994, the Company received a $1.0 million
research milestone payment from Amgen upon the filing of an IND for NT-3, as
provided for in the Amgen Agreement. In 1995, the Company entered into a
long-term manufacturing agreement with Merck, and contract manufacturing revenue
related to this agreement totaled $1.1 million. Investment income in 1995,
increased to $3.0 million from $2.6 million in 1994, primarily due to capital
losses of $0.3 million in 1994, a rise in interest rates in 1995, and interest
earned on the net proceeds of the Company's November 1995 public offering,
offset by reduced levels of interest-bearing investments in the first ten months
of the year as the Company expended funds during 1995 for capital assets,
research and development, and other operating expenses.

          The Company's total operating expenses decreased to $50.9 million in
1995 from $53.8 million in 1994. Research and development expense decreased to
$23.3 million in 1995 from $30.9 million in 1994. The Company's research and
development expenses decreased primarily due to discontinuance of the Company's
clinical study of CNTF in June 1994, when that study failed to demonstrate the
safety and efficacy of CNTF to treat ALS. This decrease was partially offset by
additional expenses related to the Company's collaboration with Sumitomo
Pharmaceuticals. Loss in Amgen-Regeneron Partners increased to $13.8 million in
1995 from $9.8 million in 1994, primarily due to increased costs related to the
initiation in the third quarter of 1995 of the Phase III BDNF clinical trial
conducted by Amgen on behalf of Amgen-Regeneron Partners. Research and


                                       25

<PAGE>

development expenses, including the loss in Amgen-Regeneron Partners, were
approximately 73% of total operating expenses in 1995, compared to 76% in 1994.

          General and administrative expense decreased to $5.8 million in 1995
from $7.5 million in 1994, primarily because the 1995 period reflected lower
costs associated with the Company's reduced staff and because the 1994 period
included a charge of approximately $0.4 million for costs associated with a 25%
reduction in workforce following the discontinuance of the Company's clinical
study of CNTF. Depreciation and amortization expense increased to $5.9 million
in 1995 from $4.2 million in 1994, reflecting depreciation of the Rensselaer
facility, which became fully operational in July 1994, equipment and leasehold
improvements placed in service during 1995, and increased patent amortization
expense. Interest expense decreased to $1.2 million in 1995 from $1.4 million in
1994. Other expenses related to recognition in the third quarter of
1995 of a $0.9 million expense as the Company's contribution to the settlement
of shareholder class action litigation.

          The Company's net loss in 1995 was $23.5 million, or $1.19 per share,
compared to a net loss of $30.7 million, or $1.62 per share, in 1994.


Liquidity and Capital Resources


          Since its inception in 1988, the Company has financed its operations
primarily through private placements and public offerings of its equity
securities, revenue earned under the several agreements between the Company and
each of Amgen, Sumitomo Chemical Company, Ltd., Sumitomo Pharmaceuticals, Merck,
Medtronic, and Procter & Gamble and investment income. In connection with the
Company's agreement to collaborate with Sumitomo Pharmaceuticals in the research
and development of BDNF in Japan, Sumitomo Pharmaceuticals paid the Company
$22.0 million and agreed to pay the Company an additional $3.0 million in 1998.
Sumitomo Pharmaceuticals has the option to cancel the 1998 payment; however, if
such a cancellation were to occur, Sumitomo Pharmaceutical's rights to develop
and commercialize BDNF in Japan would revert to the Company. In addition, the
Company is being reimbursed in connection with supplying Sumitomo
Pharmaceuticals with BDNF for preclinical use.

          Under the Amgen Agreement, Amgen was required to make defined payments
through June 1995 to the Company for research and development efforts in the
United States in connection with BDNF and NT-3. The Amgen Agreement provided
that after Amgen determined that IND applications should be filed for BDNF and
NT-3, Amgen-Regeneron Partners would thereafter conduct the
development and commercialization of these product candidates on behalf of 
Amgen-Regeneron Partners. Amgen-Regeneron Partners began operations in June 
1993 with respect to BDNF and in January 1994 with respect to NT-3. Amgen's 
required payments for BDNF and NT-3 were made directly to Regeneron prior to 
the determination by Amgen that the preparation of an IND for each compound 
should commence and thereafter to Amgen-Regeneron Partners. The Company's 
further activities relating to BDNF and NT-3, as agreed upon by Amgen and 
Regeneron, are being reimbursed by Amgen-Regeneron Partners, and the Company 
recognizes such reimbursement as revenue. The funding of Amgen-Regeneron 
Partners is through capital contributions from Amgen and Regeneron, who must 
make equal payments in order to maintain equal ownership and equal sharing of 
any profits or losses from the partnership. The Company has made capital 
contributions totaling approximately $42.6 million to Amgen-Regeneron Partners 
from the partnership's inception in June 1993 through December 31, 1996. The 
Company expects that its capital contributions in 1997 will total approximately
$3.0 million to $5.0 million. These contributions could increase or 



                                       26

<PAGE>

decrease, depending upon the cost of Amgen-Regeneron Partners conducting
additional BDNF and NT-3 preclinical and clinical studies and the outcomes of
those and other ongoing studies. Capital contributions beyond 1997 are also
anticipated to be significant.

          In September 1995, the Company entered into the Merck Agreement.
Depending on the volume of the intermediate supplied to Merck, total capital and
product payments from Merck to Regeneron could total $40.0 million or more over
the term of the agreement, which is expected to extend to 2003. This agreement
may be terminated at any time by Merck upon the payment by Merck of a
termination fee.

          From its inception in January 1988 through December 31, 1996,

exclusive of construction in progress, the Company invested approximately $47.4
million in property, plant and equipment, including $16.8 million to acquire and
renovate the Rensselaer facility and $6.1 million of new construction that is in
progress related to the modification of the facility in connection with the
Merck Agreement. In connection with the purchase and renovation of the
Rensselaer facility, the Company obtained financing of $2.0 million from the New
York State Urban Development Corporation, of which $1.8 million is outstanding.
Under the terms of such financing the Company is not permitted to declare or pay
dividends to its stockholders.

          During 1996, the Company entered into a series of new leasing
agreements (the "New Lease Line") which provides up to $4.0 million to finance
equipment acquisitions and certain building improvements, as defined,
(collectively, the "Equipment"). The Company may utilize the New Lease Line in
increments ("leases"). Lease terms are for four years after which the Company is
required to purchase the Equipment at defined amounts. Certain of the leases
will be renewed for eight months at defined monthly payments after which the
Company will own the Equipment. At December 1996, the Company had available
approximately $1.1 million of the New Lease Line.

          The Company expects that expenses related to the filing, prosecution,
defense and enforcement of patent and other intellectual property claims will
continue to be substantial as a result of patent filings and prosecutions in the
United States and foreign countries. The Company is currently involved in two
interference proceedings in the Patent and Trademark Office between Regeneron's
patent applications and patents relating to CNTF issued to Synergen, Inc. Amgen
acquired all outstanding shares of Synergen in 1994.

          As of December 31, 1996, the Company had no established banking
arrangements through which it could obtain short-term financing or a line of
credit. Additional funds may be raised through, among other things, the issuance
of additional securities, other financing arrangements, and future collaboration
agreements. No assurance can be given that additional financing will be
available or, if available, that it will be available on acceptable terms.

          At December 31, 1996, the Company had $97.0 million in cash, cash
equivalents, and marketable securities. The Company expects to incur ongoing
funding requirements for capital contributions to Amgen-Regeneron Partners to
support the continued development and clinical trials of BDNF and NT-3. The
Company also expects to incur substantial funding requirements for, among other
things, its research and development activities (including preclinical and
clinical testing), validation of its manufacturing facilities, and the
acquisition of equipment, and may incur substantial funding requirements for
expenses related to the patent interference proceedings and other patent
matters. The amount needed to fund operations will also depend on other factors,
including the status of competitive products, the success of the Company's
research and 



                                       27

<PAGE>

development programs, the status of patents and other intellectual property

rights developments, and the extent and success of any collaborative research
programs. The Company expects to incur additional capital expenditures in
connection with the renovation and validation of its Rensselaer facility
pursuant to its manufacturing agreement with Merck. However, the Company also
expects that such expenditures will be substantially reimbursed by Merck,
subject to certain conditions. The Company believes that its existing capital
resources will enable it to meet operating needs into 1999. No assurance can be
given that there will be no change in projected revenues or expenses that would
lead to the Company's capital being consumed at a faster rate than currently
expected. In order to continue to attempt to assure Regeneron's financial
condition and maximize its technological developments for the long-term benefit
of shareholders, the Company from time to time seeks additional corporate
partners and explores other opportunities to obtain research and development
funding. No assurance can be given that such partners or funding will be
available or, if available, will be on terms favorable or acceptable to the
Company.


Factors That May Affect Future Operating Results

          Regeneron cautions stockholders and investors that the following
important factors, among others, in some cases have affected, and in the future
could affect, Regeneron's actual results and could cause Regeneron's actual
results to differ materially from those expressed in any forward-looking
statements made by, or on behalf of, Regeneron. The statements under this
caption are intended to serve as cautionary statements within the meaning of the
Private Securities Litigation Reform Act of 1995. The following information is
not intended to limit in any way the characterization of other statements or
information under other captions as cautionary statements for such purpose:

o    Delay, difficulty, or failure in obtaining regulatory approval (including
     approval of its facilities for production) for the Company's products
     (including vaccine intermediate for Merck), including delays or
     difficulties in development because of insufficient proof of safety or
     efficacy.

o    Delay, difficulty, or failure of the Company's preclinical drug research
     and development programs to produce product candidates that are
     scientifically or commercially appropriate for further development by the
     Company or others.

o    Increased and irregular costs of development, regulatory approval,
     manufacture, sales, and marketing associated with the introduction of
     products in the late stage of development.

o    Cancellation or termination of material collaborative or licensing
     agreements could result in loss of research or other funding and have other
     material adverse effects on the Company and its operations. A change of
     control of one or more of the Company's material collaborators or licensees
     could also have a material adverse effect on the Company.

o    Competitive or market factors may cause use of the Company's products to be
     limited or otherwise fail to achieve broad acceptance.




                                       28

<PAGE>


o    The ability to obtain, maintain, and prosecute intellectual property
     rights, and the cost of acquiring in-process technology and other
     intellectual property rights, either by license, collaboration, or purchase
     of another entity.

o    Difficulties or high costs of obtaining adequate financing to meet the
     Company's obligations under its collaboration and licensing agreements or
     to fund 50 percent of the cost of developing product candidates in order to
     retain 50 percent of the commercialization rights.

o    Amount and rate of growth in Regeneron's selling, general, and
     administrative expenses, and the impact of unusual or infrequent charges
     resulting from Regeneron's ongoing evaluation of its business strategies
     and organizational structure.

o    Failure of corporate partners to commercialize successfully the Company's
     products or to retain and expand the markets served by the commercial
     collaborations; conflicts of interest, priorities, and commercial
     strategies which may arise between the Company and such corporate partners.

o    Difficulties in launching or marketing the Company's products by the
     Company or its licensees, especially when such products are novel products
     based on biotechnology, and unpredictability of customer acceptance of such
     products.

o    Inability to maintain or initiate third party arrangements which generate
     revenues, in the form of license fees, research and development support,
     royalties, and other payments, in return for rights to technology or
     products under development by the Company.

o    Delays or difficulties in developing and acquiring production technology
     and technical and managerial personnel to manufacture novel biotechnology
     products in commercial quantities at reasonable costs and in compliance
     with applicable quality assurance and environmental regulations and
     governmental permitting requirements.

o    Difficulties in obtaining key raw materials and supplies for the
     manufacture of the Company's product candidates.

o    The costs and other effects of legal and administrative cases and
     proceedings (whether civil, such as product-related or environmental, or
     criminal); settlements and investigations; developments or assertions by or
     against Regeneron relating to intellectual property rights and licenses;
     the issuance and use of patents and proprietary technology by Regeneron and
     its competitors, including the possible negative effect on the Company's
     ability to develop, manufacture, and sell its products in circumstances
     where it is unable to obtain licenses to patents which may be required for
     such products.


o    Underutilization of the Company's existing or new manufacturing facilities
     or of any facility expansions, resulting in inefficiencies and higher
     costs; start-up costs, inefficiencies, delays, and increased depreciation
     costs in connection with the start of production in new plants and
     expansions.

                                       29

<PAGE>

o    Health care reform, including reductions or changes in reimbursement
     available for prescription medications or other reforms.

o    The ability to attract and retain key personnel. As Regeneron's scientific
     efforts lead to potentially promising new directions, both outside of
     recombinant protein therapies (into orally active, small molecule
     pharmaceuticals) and outside of treatments for neurological and
     neurodegenerative conditions (into, for example, potential programs in
     cancer, inflammation, muscle disease, angiogenesis, and hematopoiesis), the
     Company will require additional internal expertise or external
     collaborations in areas in which it currently does not have substantial
     resources and personnel.

Impact of the Adoption of Recently Issued Accounting Standards

     In February 1997, the Financial Accounting Standards Board issued Financial
Accounting Standard No. 128, "Earnings Per Share" ("SFAS 128"). SFAS 128 will
require the Company to replace the current presentation of "primary" per share
data with "basic" and "diluted" per share data. Currently, outstanding common
stock equivalents are antidilutive and therefore management estimates that the
future adoption of SFAS 128 currently will not have a material impact on the
Company's per share data. SFAS 128 will be adopted by the Company for periods
ending after December 15, 1997.

                                       30

<PAGE>

I
tem 8. Financial Statements and Supplementary Data

          The financial statements of the Company required by this item are
included herein as exhibits and listed under Item 14.(A)1.


Item 9. Changes in and Disagreements with Accountants on Accounting and
        Financial Disclosure
  
        Not applicable.




                                    PART III




Item 10. Directors and Officers of the Registrant


          Information with respect to directors and executive officers is
incorporated by reference to the material captioned "Election of Directors,"
"Executive Officers of the Registrant," and "Compliance with Section 16(b) of
the Securities Exchange Act of 1934" in the Regeneron Pharmaceuticals, Inc.
Proxy Statement to be filed in connection with solicitation of proxies for its
Annual Meeting of Shareholders to be held on June 27, 1997.


Item 11. Executive Compensation

          The information called for by this item is incorporated by reference
to the material captioned "Executive Compensation" and "Election of Directors"
in the Regeneron Pharmaceuticals, Inc. Proxy Statement to be filed in connection
with solicitation of proxies for its Annual Meeting of Shareholders to be held
on June 27, 1997.


Item 12. Security Ownership of Certain Beneficial Owners and Management

          The information called for by this item is incorporated by reference
to the material captioned "Security Ownership of Management" and "Security
Ownership of Certain Beneficial Owners" in the Regeneron Pharmaceuticals, Inc.
Proxy Statement to be filed in connection with solicitation of proxies for its
Annual Meeting of Shareholders to be held on June 27, 1997.


Item 13. Certain Relationships and Related Transactions

          The information called for by this item is incorporated by reference
to the material captioned "Certain Relationships and Related Transactions" in
the Regeneron Pharmaceuticals, Inc. Proxy Statement to be filed in connection
with solicitation of proxies for its Annual Meeting of Shareholders to be held
on June 27, 1997.



                                       31

<PAGE>





                                     PART IV


Item 14. Exhibits, Financial Statement Schedules and Reports on Form 8-K

(A)  1.   Financial Statements

          The financials statements filed as part of this report are listed on
     the Index to Financial Statements on page F-1.

     2.   Financial Statement Schedules

     All schedules for which provision is made in the applicable accounting
     regulations of the Securities and Exchange Commission are not required
     under the related instructions or are inapplicable and therefore have been
     omitted.


     3.   Exhibits

  Exhibit
  Number  Description
  ------- -----------

     3.1  (a)   - Restated Certificate of Incorporation of Regeneron
                  Pharmaceuticals, Inc. as at June 21, 1991.
     3.2        - By-Laws of the Company, currently in effect (amended as of 
                  January 22, 1995).
     10.1 (b) * - Technology Development Agreement, dated as of March 20, 1989,
                  between the Company and Sumitomo Chemical Company, Limited.
     10.2 (b) * - Neurotrophic Factor Agreement (License Agreement), dated as of
                  May 10, 1988, between the Company and Max Planck Institute fur
                  Psychiatrie.
     10.3 (b) * - Sponsored Research and License Agreement, dated as of June 17,
                  1988, between the Company and Erziehungsdirektion of the 
                  Canton Zurich.
     10.4 (b) * - Collaboration Agreement, dated August 31, 1990, between the
                  Company and Amgen Inc.
     10.5 (b)   - 1990 Amended and Restated Long-Term Incentive Plan.
     10.6 (a) * - Neurotrophic Factor Agreement, dated as of May 21, 1991,
                  between the Company and Finn Hallbook, Carlos Fernando Ibanez 
                  Molinar, and Hakan Persson.
     10.7 (c) * - License Agreement dated as of November 19, 1991, between the
                  Company and the University of Iowa Research Foundation.
     10.8 (c) * - License Agreement dated as of January 15, 1992, between the
                  Company and Hakan Persson.
     10.9 (c) * - License Agreement dated as of January 24, 1992, between the
                  Company and Rorer Biotechnology, Inc.
     10.10(d) * - Collaborative Development Agreement dated as of September 23,
                   1992, between the Company and American Cyanamid Company.
     10.11(d) * - License Agreement dated as of October 7, 1992, between the
                  Company and The Regents of the University of California.
     10.12(e) * - Collaboration Agreement dated as of July 22, 1993 between the
                  Company and Glaxo Group Limited.
     10.13(e)  -  Stock Purchase Agreement dated as of July 22, 1993 between the
                  Company and Glaxo Group Limited.
     10.14(e)  -  Contract to Sell Real Estate dated as of July 21, 1993 between
                  the Company and National Council for Community Development 
                  Inc.
     10.15(e)  -  Renovation License Agreement dated as of July 22, 1993 between
                  the Company, National Council for Community Development and 
                  Sterling Winthrop, Inc.
     10.16(f)  -  Employment Agreement, dated as of September 14, 1993 between
                  the Company and Dr. Leonard S. Schleifer.
     10.17(g)* -  Research and Development Agreement dated as of June 2, 1994
                  between the Company and Sumitomo Pharmaceuticals Company, Ltd.
     10.18(h)* -  Manufacturing Agreement dated as of September 18, 1995
                  between the Company and Merck & Co., Inc.
     10.19(i)  -  Stock and Warrant Purchase Agreement dated as of April 15,
                  1996, between the Company and Amgen Inc.


                                       32

<PAGE>
     10.20 (i) - Warrant Agreement dated as of April 15, 1996, between the
                 Company and Amgen Inc.
     10.21 (i) - Registration Rights Agreement dated as of April 15, 1996,
                 between the Company and Amgen Inc.
     10.22 (i) - Stock and Warrant Purchase Agreement dated as of June 27, 1996,
                 between the Company and Medtronic, Inc.
     10.23 (i) - Warrant Agreement dated as of June 27, 1996, between the
                 Company and Medtronic, Inc.
     10.24 (i) - Registration Rights Agreement dated as of June 27, 1996,
                 between the Company and Medtronic, Inc.
     10.25 (i) - Assignment and Assumption Agreement dated as of June 27, 1996,
                 between the Company and Medtronic, Inc.
     10.26 (j) - Certificate of Amendment of the Restated Certificate of
                 Incorporation of Regeneron Pharmaceuticals, Inc., as at 
                 October 18, 1996.
     10.27 (k) - Rights Agreement, dated as of September 20, 1996, between
                 Regeneron Pharmaceuticals, Inc. and ChaseMellon Shareholder 
                 Services L.L.C., as Rights Agent, including the form of Rights
                 Certificate as Exhibit B thereto.
     10.28 (j) - Letter of Resignation of James W. Fordyce, Director, dated
                 October 1, 1996.
     10.29     - Stock Purchase Agreement dated as of December 11, 1996, between
                 the Company and Procter & Gamble Pharmaceuticals, Inc.
     10.30     - Registration Rights Agreement dated as of December 11, 1996,
                 between the Company and Procter & Gamble Pharmaceuticals, Inc.
     10.31 *  -  Collaboration Agreement dated as of December 11, 1996, between
                 the Company and Procter & Gamble Pharmaceuticals, Inc.
     11       -  Statement of Computation of Loss per Share.
     23.1     -  Consent of Coopers & Lybrand L.L.P.
     23.2     -  Consent of Ernst & Young LLP, Independent Auditors        
     24       - Power of Attorney
     27       - Financial Statement Data
- --------------------------------------------------------------------------------

     (a)  Incorporated by reference from the Form 10-Q of Regeneron
          Pharmaceuticals, Inc. for the quarter ended June 30,1991, filed August
          13, 1991.

     (b)  Incorporated by reference from the Company's registration statement on
          Form S-1 (file number 33-39043).

     (c)  Incorporated by reference from the Form 10-K for Regeneron
          Pharmaceuticals, Inc. for the fiscal year ended December 31, 1991,
          filed March 30, 1992. 

     (d)  Incorporated by reference from the Form 10-K for Regeneron 
          Pharmaceuticals, Inc. for the fiscal year ended December 31, 1992, 
          filed March 30, 1993.

     (e)  Incorporated by reference from the Form 10-Q of Regeneron
          Pharmaceuticals, Inc. for the quarter ended June 30,1993, filed July
          22, 1993.


     (f)  Incorporated by reference from the Form 10-Q of Regeneron
          Pharmaceuticals, Inc. for the quarter ended September 30,1993, filed
          November 12, 1993.

     (g)  Incorporated by reference from the Form 10-Q for Regeneron
          Pharmaceuticals, Inc. for the quarter ended September 30, 1994, filed
          November 14, 1994.

     (h)  Incorporated by reference from the Form 10-Q for Regeneron
          Pharmaceuticals, Inc. for the quarter ended September 30, 1995, filed
          November 14, 1995.

     (i)  Incorporated by reference from the Form 10-Q for Regeneron
          Pharmaceuticals, Inc. for the quarter ended June 30, 1996, filed
          August 14, 1996.

     (j)  Incorporated by reference from the Form 10-Q for Regeneron
          Pharmaceuticals, Inc. for the quarter ended September 30, 1996, filed
          November 5, 1996.

                                       33

<PAGE>

     (k)  Incorporated by reference from the Form 8-A for Regeneron
          Pharmaceuticals, Inc. filed October 15, 1996.



     *    Portions of this document have been omitted and filed separately with
          the Commission pursuant to requests for confidential treatment
          pursuant to Rule 24b-2.


(B)  Reports on Form 8-K 

     No report on Form 8-K was filed by the Registrant during the year ended 
December 31, 1996.


                                       34

<PAGE>
                                                       

                                    SIGNATURE

         Pursuant to the  requirements  of Section 13 or 15(d) of the Securities
Exchange Act of 1934,  the registrant has caused this report to be signed on its
behalf by the undersigned, thereunto duly authorized.

Dated:   New York, New York
         March 26, 1997
                                   REGENERON PHARMACEUTICALS, INC.



                                   By:/s/ LEONARD S. SCHLEIFER
                                      -----------------------------------------
                                          Leonard S. Schleifer, M.D., Ph.D.
                                          President and Chief Executive Officer

         Pursuant to the  requirements  of the Securities  Exchange Act of 1934,
this  report  has been  signed  below by the  following  person on behalf of the
registrant in the capacities indicated on March 26, 1997.

              Signature                                     Title
              ---------                                     -----

/s/ LEONARD S. SCHLEIFER,                 President, Chief Executive Officer, 
- ------------------------------------      and Director                        
    Leonard S. Schleifer, M.D., Ph.D.                                         
                                                                              
                                                                              
/s/ MURRAY A. GOLDBERG                    Vice President, Finance &           
- ------------------------------------      Administration, Chief Financial     
    Murray A. Goldberg                    Officer, and Treasurer (Principal   
                                          Financial Officer)                  
                                          

/s/ BEVERLY C. DUBS                       Controller and Assistant Treasurer
- ------------------------------------      (Chief Accounting Officer)
    Beverly C. Dubs                   

                  *                       Chairman of the Board
- ------------------------------------
    P. Roy Vagelos, M.D.

                  *                       Director
- ------------------------------------
    Charles A. Baker

                  *                       Director
- ------------------------------------
    Michael S. Brown, M.D.

                  *                       Director
- ------------------------------------
    Alfred G. Gilman, M.D., Ph.D.

                  *                       Director
- ------------------------------------
    Joseph L. Goldstein, M.D.

                  *                       Director
- ------------------------------------
    Fred A. Middleton

                  *                       Director
- ------------------------------------
    Eric M. Shooter, Ph.D.


                  *                       Director
- ------------------------------------
    George L. Sing


*By    /s/  PAUL LUBETKIN
- ------------------------------------
            Paul Lubetkin
           (Attorney-in-Fact)



                                       35

<PAGE>
                         REGENERON PHARMACEUTICALS, INC.


                          INDEX TO FINANCIAL STATEMENTS

                                                                         Page
Regeneron Pharmaceuticals, Inc.                                         Numbers
                                                                        -------

     Report of Independent Accountants                                    F-2

     Balance Sheets at December 31, 1996 and 1995                         F-3

     Statements of Operations for the years ended 
          December 31, 1996, 1995  and 1994                               F-4

     Statements of Stockholders' Equity for the years 
          ended December 31, 1996, 1995 and 1994                          F-5

     Statements of Cash Flows for the years ended 
          December 31, 1996, 1995 and 1994                                F-6

     Notes to Financial Statements                                 F-7 to F-18

Amgen-Regeneron Partners

     Report of Ernst & Young LLP, Independent Auditors                    F-20

     Balance Sheets at December 31, 1996 and 1995                         F-21

     Statements of Operations for the years ended 
          December 31, 1996, 1995 and 1994                                F-22

     Statements of Changes in Partners' Capital for 
          the years ended December 31, 1996,  1995 and 1994               F-23

     Statements of Cash Flows for the years ended 
          December 31, 1996, 1995 and 1994                                F-24

     Notes to Financial Statements                                F-25 to F-27





================================================================================
                                       F-1

<PAGE>

                        REPORT OF INDEPENDENT ACCOUNTANTS

To the Board of Directors and Stockholders of
Regeneron Pharmaceuticals, Inc.:

     We have audited the accompanying balance sheets of REGENERON
PHARMACEUTICALS, INC. (the "Company") as of December 31, 1996, and 1995, and the
related statements of operations, stockholders' equity, and cash flows for each
of the three years in the period ended December 31, 1996. These financial
statements are the responsibility of the Company's management. Our
responsibility is to express an opinion on these financial statements based on
our audits. We did not audit the financial statements of Amgen-Regeneron
Partners (the "Partnership"), an entity which is fifty percent owned by the
Company, as of December 31, 1996 and 1995 or for each of the three years in the
period ended December 31, 1996. The Company's investment in the Partnership is
accounted for in accordance with the equity method of accounting and constitutes
one percent of the Company's total assets at December 31, 1996 and 1995,
respectively. For the years ended December 31, 1996, 1995 and 1994 the Company
recorded its pro rata share of the Partnership's net loss of approximately $14.3
million, $13.8 million, and $9.8 million, respectively. The Partnership's
financial statements were audited by other auditors whose report has been
furnished to us, and our opinion, insofar as it relates to the amounts included
for the Partnership, is based solely on the report of the other auditors.

     We conducted our audits in accordance with generally accepted auditing
standards. Those standards require that we plan and perform the audit to obtain
reasonable assurance about whether the financial statements are free of material
misstatement. An audit includes examining, on a test basis, evidence supporting
the amounts and disclosures in the financial statements. An audit also includes
assessing the accounting principles used and significant estimates made by
management, as well as evaluating the overall financial statement presentation.
We believe that our audits and the report of the other auditors provide a
reasonable basis for our opinion.

         In our opinion, based on our audits and the report of the other
auditors, the financial statements referred to above present fairly, in all
material respects, the financial position of the Company as of December 31, 1996
and 1995, and the results of its operations and its cash flows for each of the
three years in the period ended December 31, 1996, in conformity with generally
accepted accounting principles.

                                                        COOPERS & LYBRAND L.L.P.

New York, New York 
February 14, 1997, 

except for the second 
paragraph of Note8(e) 

for which the date is 
March 19, 1997


================================================================================
                                       F-2


<PAGE>

                         REGENERON PHARMACEUTICALS, INC.
                                 BALANCE SHEETS
                           December 31, 1996 and 1995


<TABLE>
<CAPTION>
                                                                                                 1996                1995
                                     ASSETS                                                   ------------        -----------
<S>                                                                                            <C>                <C>        
Current assets
    Cash and cash equivalents                                                                  $34,475,060        $32,736,026
    Marketable securities                                                                       45,587,404         13,417,634
    Receivable due from Sumitomo Pharmaceuticals Company, Ltd.                                   2,072,455          1,749,062
    Receivable due from Merck & Co., Inc.                                                        1,816,056            271,630
    Receivable due from Amgen-Regeneron Partners                                                   446,269            668,990
    Prepaid expenses and other current assets                                                      611,435            359,111
                                                                                           ----------------    ---------------
       Total current assets                                                                     85,008,679         49,202,453

Marketable securities                                                                           16,965,302         13,468,350
Investment in Amgen-Regeneron Partners                                                           1,205,299          1,273,538
Property, plant and equipment, at cost, net of accumulated depreciation
    and amortization                                                                            34,297,843         27,870,720
Other assets                                                                                       104,731          1,996,284
                                                                                           ----------------    ---------------
       Total assets                                                                           $137,581,854        $93,811,345
                                                                                           ================    ===============

                      LIABILITIES and STOCKHOLDERS' EQUITY
Current liabilities
    Accounts payable and accrued expenses                                                       $4,357,145         $6,289,832
    Capital lease obligations, current portion                                                   3,505,221          3,408,090
    Note payable, current portion                                                                   77,684             83,444
    Deferred revenue, current portion                                                            4,108,412          3,166,665
                                                                                           ----------------    ---------------
       Total current liabilities                                                                12,048,462         12,948,031

Capital lease obligations                                                                        3,400,015          4,152,100
Note payable                                                                                     1,748,082          1,825,766
Other liabilities                                                                                  183,426            103,374

Deferred revenue                                                                                13,270,870          6,925,625

Commitments and contingencies (Notes 7, 8, and 9)


Stockholders' equity
    Preferred stock, $.01 par value; 30,000,000 shares authorized; issued and outstanding - none
    Class A Stock, convertible, $.001 par value; 40,000,000 shares authorized;
         4,355,994 shares issued and outstanding in 1996
         5,403,923 shares issued and 5,386,850 outstanding in 1995                                   4,356              5,404
   Common Stock, $.001 par value; 60,000,000 shares authorized;
        21,319,896 shares issued and outstanding in 1996
        16,465,429 shares issued and outstanding in 1995                                            21,320             16,465
    Additional paid-in capital                                                                 264,742,236        193,594,141
    Unearned compensation                                                                       (1,080,000)        (1,440,000)
    Accumulated deficit                                                                       (157,029,112)      (124,605,334)
    Net unrealized gain on marketable securities                                                   272,199            285,940
                                                                                           ----------------    ---------------
                                                                                               106,930,999         67,856,616
    Less, Class A Stock held in treasury, at cost: none in 1996; 17,073 shares in 1995              -                    (167)
                                                                                           ----------------    ---------------
       Total stockholders' equity                                                              106,930,999         67,856,449
                                                                                           ----------------    ---------------
       Total liabilities and stockholders' equity                                             $137,581,854        $93,811,345
                                                                                           ================    ===============
</TABLE>


    The accompanying notes are an integral part of the financial statements.


                                       F-3


<PAGE>
                         REGENERON PHARMACEUTICALS, INC.
                            STATEMENTS OF OPERATIONS
              for the years ended December 31, 1996, 1995, and 1994



<TABLE>
<CAPTION>
                                                                 1996                    1995                   1994
                                                          --------------------    --------------------   ---------------------
<S>                                                       <C>                     <C>                    <C>        
Revenues
     Contract research and development                            $17,302,473             $23,247,002            $19,606,292
     Investment income                                              4,360,065               2,997,180              2,585,465
     Contract manufacturing                                         2,451,424               1,140,321
     Research progress payments                                                                                    1,000,000
                                                          --------------------    --------------------   --------------------
                                                                   24,113,962              27,384,503             23,191,757
                                                          --------------------    --------------------   --------------------


Expenses
     Research and development                                      28,268,798              23,310,088             30,874,437
     Loss in Amgen-Regeneron Partners                              14,250,239              13,804,777              9,794,237
     General and administrative                                     5,879,975               5,764,397              7,529,136
     Depreciation and amortization                                  6,083,845               5,885,699              4,245,686
     Contract manufacturing                                         1,115,259                  72,059

     Interest                                                         939,624               1,204,757              1,403,001
     Other                                                                                    850,000
                                                          --------------------    --------------------   --------------------
                                                                   56,537,740              50,891,777             53,846,497
                                                          --------------------    --------------------   --------------------

Net loss                                                        ($32,423,778)           ($23,507,274)          ($30,654,740)
                                                          ====================    ====================   ====================



Net loss per share                                                    ($1.33)                 ($1.19)                ($1.62)
                                                          ====================    ====================   ====================


Weighted average number of Common
     and Class A shares outstanding                                24,463,516              19,768,466             18,866,993
                                                          ====================    ====================   ====================
</TABLE>


    The accompanying notes are an integral part of the financial statements.

                                       F-4



<PAGE>

                         REGENERON PHARMACEUTICALS, INC.
                       STATEMENTS OF STOCKHOLDERS' EQUITY
             for the years ended December 31, 1996, 1995, and 1994


<TABLE>
<CAPTION>

                                                                                                                           
                                                                                                                         
                                                             Class A Stock              Common Stock              Additional
                                                 -------------------------------- ---------------------------       Paid-in
                                                      Shares             Amount      Shares         Amount          Capital 
                                                 --------------  ---------------  -------------- ------------   -------------

<S>                                               <C>             <C>             <C>            <C>           <C>          
         Balance, December 31, 1993                   6,559,017       $6,559      $12,312,035        $12,312    $168,812,770

Issuance of Common Stock in connection
     with services rendered                                                            25,000             25          99,975
Conversion of Class A Stock to
     Common Stock                                      (933,052)        (933)         933,052            933               
Net loss, 1994                                                                                                              
Change in net unrealized gain (loss)
     on marketable securities                                                                                               
                                                      ---------    ---------    -------------     ----------   -------------
         Balance, December 31, 1994                   5,625,965        5,626       13,270,087         13,270     168,912,745


Issuance of Common Stock for cash of
     $300,000 and services to be rendered                                             600,000            600       2,099,400
Amortization of unearned compensation                                                                                       
Issuance of Common Stock in a public
     offering at $10.50 per share                                                   2,300,000          2,300      24,147,700
Cost associated with issuance of
     equity securities                                                                                            (1,895,961)
Issuance of Common Stock in connection
     with exercise of stock options                                                    73,300             73         330,257
Conversion of Class A Stock to
     Common Stock                                      (222,042)        (222)         222,042            222
Purchase of treasury stock                                                                                                 
Net loss, 1995                                                                                                             
Change in net unrealized gain (loss)
     on marketable securities                                                                                              
                                                      ---------    ---------    -------------     ----------   -------------
         Balance, December 31, 1995                   5,403,923        5,404       16,465,429         16,465     193,594,141

Issuance of Common Stock for settlement of
     an obligation                                                                    153,017            153       1,999,847
Amortization of unearned compensation
Issuance of equity securities in private placements                                 3,460,500          3,461      57,996,539
Amounts received in connection with the Stock                                                                  
     Purchase Agreement with Procter & Gamble                                                                     10,000,000
Cost associated with issuance of
     equity securities                                                                                              (205,025)
Issuance of Common Stock in connection
     with exercise of stock options                                                   210,094            210       1,356,884
Conversion of Class A Stock to
     Common Stock                                    (1,030,856)      (1,031)       1,030,856          1,031
Retirement of treasury stock                            (17,073)         (17)                                           (150)
Net loss, 1996
Change in net unrealized gain (loss)
     on marketable securities
- ---------------------------------------------------------------------------------------------------------------------------
         Balance, December 31, 1996                   4,355,994       $4,356       21,319,896        $21,320    $264,742,236
===========================================================================================================================

<CAPTION>
                                                                                                       Net Unrealized       
                                                                                                       Gain (Loss) on    
                                                          Unearned             Accumulated               Marketable      
                                                         Compensation           Deficit                  Securities      
                                                         --------------   ----------------------     ----------------- 
<S>                                                  <C>                  <C>                        <C>          
         Balance, December 31, 1993                                          ($70,443,320)                                   
                                                                                                                             
Issuance of Common Stock in connection                                                                                       
     with services rendered                                                                                                  
Conversion of Class A Stock to                                                                                               
     Common Stock                                                                                                            
Net loss, 1994                                                                (30,654,740)                                   
Change in net unrealized gain (loss)                                                                                         
     on marketable securities                                                                           ($762,852)           

                                                     -------------          -------------           -------------            
         Balance, December 31, 1994                                          (101,098,060)               (762,852)           
                                                                                                                             
Issuance of Common Stock for cash of                                                                                         
     $300,000 and services to be rendered              ($1,800,000)                                                          
Amortization of unearned compensation                      360,000                                                           
Issuance of Common Stock in a public                                                                                        
     offering at $10.50 per share   
Cost associated with issuance of                                                                                             
     equity securities                            
Issuance of Common Stock in connection                                                                                       
     with exercise of stock options               
Conversion of Class A Stock to                                                                                               
     Common Stock                                                                                                            
Purchase of treasury stock                        
Net loss, 1995                                                                (23,507,274)                                   
Change in net unrealized gain (loss)                                                                                         
     on marketable securities                                                                           1,048,792            
                                                     -------------          -------------           -------------            
         Balance, December 31, 1995                     (1,440,000)          (124,605,334)                285,940            
                                                                                                                             
Issuance of Common Stock for settlement of                                                                                   
     an obligation                                
Amortization of unearned compensation                      360,000 
Issuance of equity securities in private placements                                  
Amounts received in connection with the Stock                                       
     Purchase Agreement with Procter & Gamble                                       
Cost associated with issuance of                                                    
     equity securities                                                              
Issuance of Common Stock in connection                                              
     with exercise of stock options                                                 
Conversion of Class A Stock to                                                      
     Common Stock                                                                   
Retirement of treasury stock                                                        
Net loss, 1996                                                                (32,423,778)                                 
Change in net unrealized gain (loss)                                                                                         
     on marketable securities                                                                             (13,741)
                                       --------------------------------------------------------------------------------------
         Balance, December 31, 1996                    ($1,080,000)         ($157,029,112)               $272,199           
                                       ======================================================================================
                                                                                                                             
<CAPTION>
                                                                         
                                                           Class A Stock     
                                                         Held in Treasury                  Total    
                                                    ---------------------------      Stockholders' 
                                                      Shares         Amount              Equity
                                                    --------------  -----------  --------------------

<S>                                                 <C>             <C>          <C>
         Balance, December 31, 1993                         16,559      ($162)       $98,388,159
                                                                                 
Issuance of Common Stock in connection                                           
     with services rendered                                                              100,000

Conversion of Class A Stock to                                                   
     Common Stock                                                                
Net loss, 1994                                                                       (30,654,740)
Change in net unrealized gain (loss)                                             
     on marketable securities                                                           (762,852)
                                                     -------------   --------      -------------
         Balance, December 31, 1994                         16,559       (162)        67,070,567
                                                                                 
Issuance of Common Stock for cash of                                             
     $300,000 and services to be rendered                                                300,000
Amortization of unearned compensation                                                    360,000
Issuance of Common Stock in a public                                             
     offering at $10.50 per share                                                     24,150,000
Cost associated with issuance of                                                 
     equity securities                                                                (1,895,961)
Issuance of Common Stock in connection                                           
     with exercise of stock options                                                      330,330
Conversion of Class A Stock to                                                   
     Common Stock                                                                
Purchase of treasury stock                                     514         (5)                (5)
Net loss, 1995                                                                       (23,507,274)
Change in net unrealized gain (loss)                                             
     on marketable securities                                                          1,048,792
                                                     -------------   --------      -------------
         Balance, December 31, 1995                         17,073       (167)        67,856,449
                                                                                 
Issuance of Common Stock for settlement of                                       
     an obligation                                                                     2,000,000
Amortization of unearned compensation                                                    360,000
Issuance of equity securities in private placement                                    58,000,000
Amounts received in connection with the Stock                                     
     Purchase Agreement with Procter & Gamble                                         10,000,000
Cost associated with issuance of                                                 
     equity securities                                                                  (205,025)
Issuance of Common Stock in connection                                           
     with exercise of stock options                                                    1,357,094
Conversion of Class A Stock to                                                   
     Common Stock                                                                
Retirement of treasury stock                               (17,073)      (167)   
Net loss, 1996                                                                       (32,423,778)
Change in net unrealized gain (loss)                                             
     on marketable securities                                                            (13,741)
                                              --------------------------------------------------
                                                                                 
         Balance, December 31, 1996                           --         --        $ 106,930,999
                                              ==================================================
</TABLE>


The accompanying notes are an integral part of the financial statements.
===============================================================================
                                                 
                                      F-5  


<PAGE>

                         REGENERON PHARMACEUTICALS, INC.
                            STATEMENTS OF CASH FLOWS
             for the years ended December 31, 1996, 1995, and 1994
                Increase (Decrease) in Cash and Cash Equivalents

<TABLE>
<CAPTION>
                                                                                           1996                      1995           
                                                                                           ----                      ----           
<S>                                                                                <C>                       <C>                    
Cash flows from operating activities
    Net loss                                                                                ($32,423,778)             ($23,507,274) 
                                                                                   ----------------------    ---------------------- 
    Adjustments to reconcile net loss to net cash
         used in operating activities
             Share of net loss of Amgen-Regeneron Partners                                    14,250,239                13,804,777  
             Depreciation and amortization                                                     6,083,845                 5,905,791  
             Amortization of lease incentive                                                                               (50,300) 
             Loss on sales of marketable securities                                                                                 
             Stock issued in consideration for services rendered                                 360,000                   360,000  
             Changes in assets and liabilities
                  Decrease (increase) in amounts due from Amgen-Regeneron Partners               222,721                   324,664  
                  Increase in amounts due from Sumitomo Pharmaceuticals Co., Ltd.               (323,393)               (1,749,062)
                  Increase in amounts due from Merck & Co., Inc.                              (1,544,426)                 (271,630)
                  Increase in investment in Amgen-Regeneron Partners                         (14,182,000)              (13,422,000) 
                  Decrease in prepaid expenses and other assets                                  356,353                    26,182  
                  Increase in deferred revenue                                                 7,286,992                   842,288  
                  Decrease in accounts payable, accrued expenses,
                      and other liabilities                                                     (368,427)                 (502,203) 
                                                                                   ----------------------    ---------------------- 
                             Total adjustments                                                12,141,904                 5,268,507  
                                                                                   ----------------------    ---------------------- 
                  Net cash used in operating activities                                      (20,281,874)              (18,238,767) 
                                                                                   ----------------------    ---------------------- 


Cash flows from investing activities
    Purchase of marketable securities                                                        (74,606,782)              (28,084,233) 
    Sale of marketable securities                                                             38,926,319                38,816,383  
    Capital expenditures                                                                      (8,622,133)               (3,342,040) 
                                                                                   ----------------------    ---------------------- 
                  Net cash (used in) provided by  investing activities                       (44,302,596)                7,390,110  
                                                                                   ----------------------    ---------------------- 

Cash flows from financing activities
    Net proceeds from the issuance of equity securities                                       69,963,916                23,222,522
    Proceeds from note payable                                                                                                      
    Principal payments on note payable                                                           (83,444)                  (90,790)
    Capital lease payments                                                                    (3,556,968)               (3,192,958) 
    Purchase of treasury stock                                                                                                  (5)
                                                                                   ----------------------    ---------------------- 
                  Net cash provided by (used in) financing activities                         66,323,504                19,938,769  
                                                                                   ----------------------    ---------------------- 
                  Net increase in cash and cash equivalents                                    1,739,034                 9,090,112  
                                                                                   ----------------------    ---------------------- 
Cash and cash equivalents at beginning of year                                                32,736,026                23,645,914  
                                                                                   ----------------------    ---------------------- 
                  Cash and cash equivalents at end of year                                   $34,475,060               $32,736,026  
                                                                                   ======================    ====================== 


Supplemental disclosure of cash flow information
    Cash paid for interest                                                                      $859,572                $1,101,383  
                                                                                   ======================    ====================== 

<CAPTION>
                                                                                           1994
                                                                                           ----
<S>                                                                                <C>          
Cash flows from operating activities
    Net loss                                                                                ($30,654,740)
                                                                                   ----------------------
    Adjustments to reconcile net loss to net cash
         used in operating activities
             Share of net loss of Amgen-Regeneron Partners                                     9,794,237
             Depreciation and amortization                                                     4,245,686
             Amortization of lease incentive                                                    (150,888)
             Loss on sales of marketable securities                                              315,384
             Stock issued in consideration for services rendered                                 100,000
             Changes in assets and liabilities
                  Decrease (increase) in amounts due from Amgen-Regeneron Partners              (429,863)
                  Increase in amounts due from Sumitomo Pharmaceuticals Co., Ltd. 
                  Increase in amounts due from Merck & Co., Inc.                  
                  Increase in investment in Amgen-Regeneron Partners                         (11,218,345)
                  Decrease in prepaid expenses and other assets                                1,330,298
                  Increase in deferred revenue                                                 8,416,669
                  Decrease in accounts payable, accrued expenses,
                      and other liabilities                                                   (2,267,256)
                                                                                   ----------------------

                             Total adjustments                                                10,135,922
                                                                                   ----------------------
                  Net cash used in operating activities                                      (20,518,818)
                                                                                   ----------------------

Cash flows from investing activities
    Purchase of marketable securities                                                        (22,526,927)
    Sale of marketable securities                                                             61,341,406
    Capital expenditures                                                                      (6,948,027)
                                                                                   ----------------------
                  Net cash (used in) provided by  investing activities                        31,866,452
                                                                                   ----------------------

Cash flows from financing activities
    Net proceeds from the issuance of equity securities                           
    Proceeds from note payable                                                                 2,000,000
    Principal payments on note payable                                            
    Capital lease payments                                                                    (2,234,735)
    Purchase of treasury stock                                                    
                                                                                   ----------------------
                  Net cash provided by (used in) financing activities                           (234,735)
                                                                                   ----------------------
                  Net increase in cash and cash equivalents                                   11,112,899
                                                                                   ----------------------
Cash and cash equivalents at beginning of year                                                12,533,015
                                                                                   ----------------------
                  Cash and cash equivalents at end of year                                   $23,645,914
                                                                                   ======================


Supplemental disclosure of cash flow information
    Cash paid for interest                                                                    $1,403,001
                                                                                   ======================
</TABLE>


    The accompanying notes are an integral part of the financial statements.

================================================================================

                                      F-6

<PAGE>

                         REGENERON PHARMACEUTICALS, INC.

                          NOTES TO FINANCIAL STATEMENTS
              for the years ended December 31, 1996, 1995, and 1994


1.   Organization and Business

         Regeneron Pharmaceuticals, Inc. (the "Company") was incorporated in
January 1988 in the State of New York. The Company is engaged in research and
development programs to discover and commercialize therapeutics to treat human
disorders and conditions. The Company's facilities are located in New York.  The
Company's business is subject to certain risks including, but not limited to
uncertainities relating to conducting pharmaceutical research, obtaining
regulatory approvals, commercializing products, and obtaining and enforcing
patents.

2.   Summary of Significant Accounting Policies

         Property, Plant and Equipment
         Property, plant, and equipment are stated at cost. Depreciation is
provided on a straight-line basis over the estimated useful lives of the assets.
Expenditures for maintenance and repairs which do not materially extend the
useful lives of the assets are charged to expense as incurred. The cost and
accumulated depreciation or amortization of assets retired or sold are removed
from the respective accounts, and any gain or loss is recognized in operations.
The estimated useful lives of property, plant, and equipment are as follows:

         Building and improvements                   30 years
         Leasehold improvements                      Life of lease
         Laboratory and computer equipment           3-5 years
         Furniture and fixtures                      5 years

         Cash and Cash Equivalents
         For purposes of the statement of cash flows and the balance sheet, the
Company considers all highly liquid debt instruments with a maturity of three
months or less when purchased to be cash equivalents. The carrying amount
reported in the balance sheet for cash and cash equivalents approximates its
fair value.

         Revenue Recognition
         Revenue from contract research and development and contract
manufacturing is recognized as the related services are performed by the
Company, provided the collection of the resulting receivable is probable. In
situations where the Company receives payments in advance of the performance of
services, such amounts are deferred and recognized as revenue as the related
services are performed.

         Net  Loss Per Share
         Net loss per share is computed on the basis of the net loss for the
period divided by the weighted average number of shares of Common Stock and
Class A Stock outstanding during the period. The net loss per share for all
periods presented excludes the number of shares issuable upon exercise of
outstanding stock options and warrants since such inclusion would be
anti-dilutive.


         Income Taxes
         The Company accounts for income taxes in accordance with the provisions
of Statement of Financial Accounting Standards No. 109, "Accounting for Income
Taxes" ("SFAS 109"). SFAS 109 requires that the Company recognize deferred tax
liabilities and assets for the expected future tax consequences of events that
have been included in the financial statements or tax returns. Under this
method, deferred tax liabilities and assets are determined on the basis of the
difference between the tax basis of assets and liabilities and their respective
financial reporting amounts ("temporary differences") at enacted tax rates in
effect for the years in which the differences are expected to reverse.

         Concentrations of Credit Risk
         Financial instruments which potentially subject the Company to
concentrations of credit risk consist of cash, cash equivalents, marketable
securities, and receivables from Amgen-Regeneron Partners, Sumitomo
Pharmaceuticals Company, Ltd., and Merck & Co., Inc. The Company generally
invests its excess cash in obligations of the U.S. government and its agencies,
bank deposits, and investment grade debt securities issued by corporations,
governments, and financial institutions. The Company has established guidelines
that relate to credit quality, diversification, and maturity and that limit
exposure to any one issue of securities.



                                      F-7

<PAGE>

                         REGENERON PHARMACEUTICALS, INC.
                    NOTES TO FINANCIAL STATEMENTS (Continued)

         Risks and Uncertainties
         The Company has had no product sales and there is no assurance that the
Company's research and development efforts will be successful, that the Company
will ever have commercially approved products, or that the Company will achieve
significant sales of any such products. The Company has incurred net losses and
negative cash flows from operations since its inception, and revenues to date
have been limited to payments for research from four collaborators and for
contract manufacturing from one pharmaceutical company and investment income
(see Notes 8 and 9). In addition, the Company operates in an environment of
rapid change in technology and is dependent upon the services of its employees,
consultants, and collaborators.

         The preparation of financial statements in conformity with generally
accepted accounting principles requires management to make estimates and
assumptions that affect the amounts reported in the financial statements and
accompanying notes. Actual results could differ from those estimates.

         Stock-based Employee Compensation
         The accompanying financial position and results of operations of the
Company have been prepared in accordance with APB Opinion No. 25, Accounting for
Stock Issued to Employees ("APB No. 25"). Under APB No. 25, generally, no
compensation expense is recognized in the accompanying financial statements in
connection with the awarding of stock option grants to employees provided that,

as of the grant date, all terms associated with the award are fixed and the
quoted market price of the Company's stock, as of the grant date, is equal to or
less than the amount an employee must pay to acquire the stock as defined.

         Disclosures required by Statement of Financial Accounting Standards No.
123, Accounting for Stock-Based Compensation ("SFAS No. 123"), including pro
forma operating results had the Company prepared its financial statements in
accordance with the fair value based method of accounting for stock-based
compensation, have been included in Note 10.

         Impact of the Adoption of Recently Issued Accounting Standards
         In February 1997, the Financial Accounting Standards Board issued
Financial Accounting Standard No. 128. "Earnings Per Share" ("SFAS 128"). SFAS
128 will require the Company to replace the current presentation of "primary"
per share data with "basic" and "diluted" per share data. Currently, outstanding
common stock equivalents are antidilutive and therefore management estimates
that the future adoption of SFAS 128 currently will not have a material impact
on the Company's per share data. SFAS 128 will be adopted by the Company for
periods ending after December 15, 1997.

         Statement of Cash Flows
         Supplemental disclosure of noncash investing and financing activities:

         Capital lease obligations of approximately $2.9 million, $0.4 million,
and $5.1 million were incurred when the Company acquired new equipment in 1996,
1995, and 1994, respectively.

         During January 1995, the Company issued 600,000 restricted shares of
Common Stock ("Restricted Shares"), in consideration for $0.3 million and
services to be rendered, in connection with an agreement with the Chairman of
the Board of Directors. The difference between the fair market value of the
Common Stock on the date the agreement was signed and the purchase price of the
Restricted Shares was $1.8 million which the Company is recognizing as
compensation expense on a pro rata basis over five years as the restriction on
the Restricted Shares lapses.

         During 1994, the Company issued 25,000 shares of Common Stock to a
financial advisor as compensation for services rendered to the Company. The fair
market value of such shares at the date of issuance was $0.1 million.

         Included in accounts payable and accrued expenses at December 31, 1996
and 1995 were approximately $0.8 million and $1.1 million of capital
expenditures. Included in accounts payable and accrued expenses at December 31,
1995 were $0.3 million of costs incurred in connection with the Company's sale
of Common Stock.

         Reclassifications
         Certain reclassifications have been made to the financial statements
for 1995 and 1994 in order to conform with the current year's presentation.


3.   Marketable Securities

         The Company considers its marketable securities to be

"available-for-sale," as defined by Statement of Financial Accounting Standards
No. 115, "Accounting for Certain Investments in Debt and Equity Securities"
("SFAS 115"), and, accordingly, unrealized holding gains and losses are excluded
from operations and reported as a net amount in a separate component of
stockholders' equity.




                                      F-8

<PAGE>

                         REGENERON PHARMACEUTICALS, INC.
                    NOTES TO FINANCIAL STATEMENTS (Continued)


         The following tables summarize the amortized cost basis of marketable
securities, the aggregate fair value of marketable securities, and gross
unrealized holding gains and losses at December 31, 1996 and 1995:


<TABLE>
<CAPTION>
                                                                                 Unrealized
                                                                                   Holding
                                              Amortized       Fair                 -------
At December 31, 1996                          Cost Basis      Value      Gains     (Losses)     Net
- --------------------                          ----------      -----      -----     --------     ---
<S>                                         <C>          <C>          <C>         <C>         <C>    
Maturities within one year                
   Corporate debt securities                 $7,120,080   $7,145,700     $28,363     $(2,743)    $25,620
   U.S. Government securities                38,205,193   38,441,704     257,096     (20,585)    236,511
                                             ----------   ----------  ----------  ----------  ----------
                                             45,325,273   45,587,404     285,459     (23,328)    262,131
                                             ----------   ----------  ----------  ----------  ----------
Maturities between one and three years                                                        
   Corporate debt securities                 10,982,405   10,994,489      16,411      (4,327)     12,084
   U.S. Government securities                 5,972,829    5,970,813      26,253     (28,269)     (2,016)
                                             ----------   ----------  ----------  ----------  ----------
                                             16,955,234   16,965,302      42,664     (32,596)     10,068
                                             ----------   ----------  ----------  ----------  ----------
                                            $62,280,507  $62,552,706    $328,123    $(55,924)   $272,199
                                             ==========   ==========  ==========  ==========  ==========
                                                                                              
At December 31, 1995                                                                          
Maturities within one year                                                                    
   Corporate debt securities                 $6,190,186   $6,244,035     $53,849     $    --     $53,849
   U.S. Government securities                 7,059,037    7,173,599     139,016     (24,454)    114,562
                                             ----------   ----------  ----------  ----------  ----------
                                             13,249,223   13,417,634     192,865     (24,454)    168,411
                                             ----------   ----------  ----------  ----------  ----------
Maturities between one and three years                                                                                         
   Corporate debt securities                  6,028,051    6,141,731     113,680      ---        113,680
   U.S. Government securities                 7,322,770    7,326,619      13,767      (9,918)      3,849
                                             ----------   ----------  ----------  ----------  ----------

                                             13,350,821   13,468,350     127,447      (9,918)    117,529
                                             ----------   ----------  ----------  ----------  ----------
                                            $26,600,044  $26,885,984    $320,312    ($34,372)    285,940
                                             ==========   ==========  ==========  ==========  ==========
                                          
</TABLE>

                            
                        
         The aggregate net unrealized gain has been included as an increase to
stockholders' equity at December 31, 1996 and 1995.

         Realized gains and losses are included as a component of investment
income. For the years ended December 31, 1996, 1995 and 1994, gross realized
gains and losses were not significant. In computing realized gains and losses,
the Company computes the cost of its investments on a specific identification
basis. Such cost includes the direct costs to acquire the securities, adjusted
for the amortization of any discount or premium. The fair value of marketable
securities has been estimated based on quoted market prices.

4.  Property, Plant, and Equipment

         Property, plant, and equipment as of December 31, 1996 and 1995 consist
of the following:

                                                       1996             1995
                                                       ----             ----
Land                                             $    474,501    $     474,501
Building and improvements                          22,573,914       16,300,026
Leasehold improvements                              6,165,487        6,147,652
Construction in progress                            6,131,873        3,885,730
Laboratory equipment                               17,248,902       14,931,715
Furniture, fixtures, and computer equipment           906,948          533,929
                                                  ------------     ------------
                                                   53,501,625       42,273,553
Less, accumulated depreciation and amortization   (19,203,782)     (14,402,833)
                                                  ------------     ------------
                                                  $34,297,843      $27,870,720
                                                  ============     ============


         Depreciation and amortization expense on property, plant, and equipment
amounted to approximately $4.8 million, $4.6 million, and $3.9 million for the
years ended December 31, 1996, 1995, and 1994, respectively.





                                      F-9

<PAGE>


                  REGENERON PHARMACEUTICALS, INC.
                    NOTES TO FINANCIAL STATEMENTS (Continued)


5.  Accounts Payable and Accrued Expenses

         Accounts payable and accrued expenses as of December 31, 1996 and 1995
consist of the following:

                                               1996             1995
                                               ----             ----

Accounts payable                          $ 2,178,308      $ 3,240,050
Accrued payroll and related costs           1,047,812        1,054,626
Accrued clinical trial expense                319,500          350,000
Accrued litigation settlement                   -- --          850,000
Accrued expenses, other                       389,062          299,412
Deferred compensation                         422,463          495,744
                                          -----------      -----------
                                          $ 4,357,145      $ 6,289,832
                                          ===========      ===========


6.  Stockholders' Equity

         The Company's Amended Certificate of Incorporation (the "Amendments")
provides for the issuance of up to 40 million shares of Class A Stock, par value
$0.001 per share, and 60 million shares of Common Stock, par value $0.001 per
share. Each share of Class A Stock is convertible, at any time, at the option of
the holder into shares of Common Stock on a share-for-share basis and holders of
Class A Stock have rights and privileges identical to Common Stockholders except
that Class A Stockholders are entitled to ten votes per share while Common
Stockholders are entitled to one vote per share. Class A Stock may only be
transferred to specified Permitted Transferees, as defined. The Amendments also
provide for the Company's Board of Directors (the "Board") to issue preferred
stock, par value $.01 per share, authorized 30 million shares, in series, with
rights, privileges, and qualifications of each series determined by the Board.

         During January 1995, the Company entered into an agreement with the
Chairman of the Board. As partial consideration for services to be rendered, the
agreement provided for the Company to sell the Chairman 600,000 restricted
shares of Common Stock ("Restricted Shares"), in consideration for $0.3 million,
and to grant 285,000 stock options. The Restricted Shares are nontransferable
with such restriction lapsing ratably over a five year period. In accordance
with generally accepted accounting principles, the Company is recognizing
compensation expense for the difference between the fair market value of the
Common Stock on the date the agreement was signed and the purchase price of the
Restricted Shares on a pro rata basis over five years as the restriction on the
Restricted Shares lapses. The unamortized balance of unearned compensation at
December 31, 1996 (approximately $1.1 million) has been included as a reduction
to stockholders' equity. For the years ended December 31, 1996 and 1995, the
Company recognized compensation expense of approximately $0.4 million in each
year. The stock options, which have been issued under the Company's Amended and
Restated 1990 Long-Term Incentive Plan, entitle the holder to purchase an equal
number of shares of Common Stock at a per share price of $3.50, the fair market
value of the Common Stock on the date of grant. The options vest over a five
year period.


         During April 1996, Amgen Inc. purchased from the Company 3 million
shares of Common Stock and 700,000 warrants for $48.0 million. The warrants have
an exercise price of $16 per share, are fully exercisable, expire on April 15,
2001, and are subject to anti-dilution provisions, and other defined
adjustments.

         During June 1996, Medtronic, Inc. purchased from the Company 460,500
shares of Common Stock and 107,400 warrants for $10.0 million. The warrants have
an exercise price of $21.72 per share, are fully exercisable, expire on June 26,
2001, and are subject to anti-dilution provisions and other defined adjustments.

         During September 1996, the Company announced that it adopted a
Shareholder Rights Plan in which Rights were distributed as a dividend at the
rate of one Right for each share of Common Stock and Class A Stock
(collectively, "Stock") held by shareholders of record as of the close of
business on October 18, 1996. Each Right initially entitles the registered
holder to buy a unit ("Unit") consisting of one-one thousandth of a share of
Series A Junior Participating Preferred Stock ("A Preferred Stock") at a
purchase price of $120 per Unit (the "Purchase Price"). Initially the Rights
were attached to all Stock certificates representing shares then outstanding,
and no separate Rights certificate were distributed. The Rights will separate
from the Stock and a "distribution date" will occur upon the earlier of (i) ten
days after a public announcement that a person or group of affiliated or
associated persons, excluding certain defined persons, (an "Acquiring Person")
has acquired, or has obtained the right to acquire, beneficial ownership of 20%
or more of the outstanding shares of Stock or (ii) ten business days following
the commencement of a tender offer or exchange offer that would result in a
person or group beneficially owning 



                                      F-10

<PAGE>

                  REGENERON PHARMACEUTICALS, INC.
                    NOTES TO FINANCIAL STATEMENTS (Continued)

20% or more of such outstanding shares of Stock. The Rights are not exercisable
unless a distribution date occurs and will expire at the close of business on
October 18, 2006 unless earlier redeemed by the Company, subject to certain
defined restrictions, for $.01 per Right. In the event that an Acquiring Person
becomes the beneficial owner of 20% or more of the then outstanding shares of
Stock (unless such acquisition is made pursuant to a tender or exchange offer
for all outstanding shares of the Company, at a price determined by a majority
of the independent directors of the Company who are not representatives,
nominees, affiliates, associates of an Acquiring Person to be fair and otherwise
in the best interest of the Company and its shareholders after receiving advice
from one or more investment banking firms), each Right will entitle the holder
to purchase, at the Right's then current exercise price, common shares (or, in
certain circumstances, cash, property or other securities of the Company) having
a value twice the Right's Exercise Price. The Right's Exercise Price is the
Purchase Price times the number of shares of Common Stock associated with each
Right (initially, one). Upon the occurrence of any such events, the Rights held

by an Acquiring Person become null and void. In certain circumstances, a Right
entitles the holder to receive, upon exercise, shares of common stock of an
acquiring company having a value equal to two times the Right's Exercise Price.

         As a result of the Shareholder Rights Plan, the Company's Board
designated 100,000 shares of preferred stock as A Preferred Stock. The A
Preferred Stock has certain preferences, as defined.

         In November 1996, the Company's Board authorized the retirement of
17,073 shares of Class A Stock which had been held as treasury shares. The
retired shares will have the status of authorized but unissued stock and will
retain the classification of Class A Stock.

7.  Commitments and Contingencies

         a.  Operating Leases
         The Company leases laboratory and office space under an operating lease
agreement, expiring June 30, 1998, with renewal options for two additional
five-year periods. The lease, as amended, provides for base rent plus additional
rental charges based upon increases in taxes and operating expenses, as defined.

         The Company leases certain laboratory and office equipment under
operating leases which expire at various times through 1998. Operating leases
entered into with one lessor contain a negative covenant agreement which
requires, among other things, that the Company maintain certain levels of
minimum cash, net worth, and other financial ratios, as defined.

         At December 31, 1996, the future minimum noncancelable lease
commitments under operating leases are as follows:

                           Laboratory and
  December 31,              Office Space       Equipment          Total
  ------------              ------------       ---------          -----
      1997                   $2,697,894         $456,401      $3,154,295
      1998                    1,348,947           72,575       1,421,522
                              ---------        ---------       ---------
                             $4,046,841         $528,976      $4,575,817
                              =========        =========       =========


         Rent expense under operating leases was:

                                  Laboratory and
    Year Ending December 31,       Office Space      Equipment           Total
    ------------------------       ------------      ---------           -----
              1996                  $2,738,226        $669,300      $3,407,526
              1995                   2,715,294         921,269       3,636,563
              1994                   2,648,819       1,091,806       3,740,625


         b.  Capital Leases
         The Company leases equipment under noncancelable capital leases. Lease
terms range from four to five years after which the Company is required to
purchase the equipment at amounts defined by the agreements, or the leases will

automatically be extended for one additional year at defined monthly payments.
The leases, as amended, have various financial covenants which include minimum
levels of liquid assets, as defined, of $30 million and tangible net worth, as
defined, of $35 million.



                                      F-11

<PAGE>

                  REGENERON PHARMACEUTICALS, INC.
                    NOTES TO FINANCIAL STATEMENTS (Continued)

         During 1996, the Company entered into a series of new leasing
agreements (the "New Lease Line") which provides up to $4.0 million to finance
equipment acquisitions and certain building improvements, as defined,
(collectively, the "Equipment"). The Company may utilize the New Lease Line in
increments ("leases"). Lease terms are for four years after which the Company is
required to purchase the Equipment at defined amounts. Certain of the leases
will be renewed for eight months at defined monthly payments after which the
Company will own the Equipment. At December 1996, the Company had available
approximately $1.1 million of the New Lease Line.

         As of December 31, 1996, minimum rental payments under all capital
leases, including payments to acquire leased equipment, are as follows:

                                                                Minimum
       Year Ending December 31,                         Rental Payments
       ------------------------                         ---------------
                 1997                                       $ 4,390,977
                 1998                                         1,843,022
                 1999                                           871,363
                 2000                                           748,732
                 2001                                            78,561
                                                             ----------
                                                              7,932,655
Less, amounts representing interest                          (1,027,419)
                                                             ----------
Present value of net minimum capital lease payments          $6,905,236
                                                             ==========

         Leased equipment and building improvements in property, plant, and
equipment was approximately $17.5 million and $14.6 million at December 31, 1996
and 1995, respectively; related accumulated depreciation was approximately $12.0
million and $8.8 million for the same respective periods.

         c.   Note Payable
         During November 1994, the Company borrowed $2.0 million from the New
York State Urban Development Corporation ("NYS UDC"). The terms of the note
provide for monthly payments of principal and interest through December 2014.
Outstanding borrowings accrue interest at an effective interest rate of
approximately 6.3%. The note is collateralized by a first mortgage on the
Company's land, building, and improvements in Rensselaer, New York (book value
at December 31, 1996 was approximately $30.6 million). The note also has various

financial covenants which include a minimum ratio of current assets over current
liabilities, as defined, and a minimum level of tangible net worth, as defined,
of $35.0 million. In addition, the Company is not permitted to declare or pay
dividends to its stockholders. The provisions of the note call for the Company
to meet certain defined levels of employment; otherwise, the interest rate on
outstanding borrowings will increase to 2.0% above the prime rate (as defined)
until the defined levels of employment are attained. As of January 1, 1997, the
Company did not meet the defined levels of employment and, accordingly, the
interest rate charged on outstanding borrowings will increase to 2.0% above the
prime rate effective March 1, 1997. The estimated fair value of the Company's
note payable to the NYS UDC at December 31, 1996 was approximately $2.0 million.
The fair value was estimated based on the current rate offered to the Company
for debt with similar terms.

         Principal payments under the note during each of the next five years,
and thereafter, are as follows:

                                          1997              $77,684
                                          1998               73,298
                                          1999               70,128
                                          2000               68,064
                                          2001               67,042
                                    Thereafter            1,469,550
                                                         ----------
                                                         $1,825,766
                                                         ==========

         d.  Research Collaboration and Licensing Agreements
         As part of the Company's research and development efforts, the Company
enters into research collaboration and licensing agreements ("Agreements") with
related and unrelated scientific collaborators, universities, or consultants
(collectively, the "Scientists"). These Agreements contain varying terms and
provisions which include fees to be paid by the Company and services to be
provided by, or rights to certain proprietary technology developed by, the
Scientists. Some of the Agreements contain provisions which require the Company
to pay royalties to the Scientists, as defined, in the event the Company sells
or licenses any proprietary products developed under the respective Agreements.




                                      F-12

<PAGE>
                  REGENERON PHARMACEUTICALS, INC.
                    NOTES TO FINANCIAL STATEMENTS (Continued)


         Certain Agreements, where the Company is required to pay fees, provide
for the Company, upon 30 to 90-day written notice, to terminate such Agreements.
During the three years ended December 31, 1996, the Company incurred expenses
related to these Agreements of approximately $0.5 million, $0.5 million, and
$0.6 million, respectively.

         e.  Deferred Compensation

         The Company has entered into compensation agreements with certain
employees and outside consultants. These agreements require the Company to make
certain payments in the future, as defined by the respective agreements. The
Company provides for such expenditures over the employment/service period. Such
accrual amounted to approximately $0.4 million and $0.5 million at December 31,
1996 and 1995, respectively.

8.  Collaboration Agreements

         a.  Amgen Inc.
         In August 1990, the Company entered into a collaboration agreement (the
"Amgen Agreement") with Amgen Inc. ("Amgen") to develop and attempt to
commercialize two proprietary products (BDNF and NT-3, individually the
"Product," collectively the "Products"). The Amgen Agreement, among other
things, provides for Amgen to fund defined amounts ("Minimum Annual Funding") of
development costs of the Products and for Amgen and the Company to form a
partnership ("Amgen-Regeneron Partners" or the "Partnership") to complete the
development and to commercialize the Products after a defined level of
development has occurred. In June 1993, the Partnership commenced operations,
with Amgen and the Company holding equal ownership interests (subject to
adjustment for any future inequities in capital contributions, as defined). The
Partnership is the exclusive distributor of Products in the United States, and
Amgen has received a license from the Company to market the Products outside the
United States and outside Japan and certain Pacific Rim countries. The Company
accounts for its investment in the Partnership in accordance with the equity
method of accounting. Since the Partnership's inception, the Company has
contributed capital to the Partnership of approximately $42.6 million. In 1996,
1995, and 1994, the Company recognized its share of the Partnership net loss in
the amounts of approximately $14.3 million, $13.8 million, and $9.8 million,
respectively, which represents 50% of the total Partnership net loss, after
first allocating certain defined amounts to Amgen ($2.5 million and $5.0 million
for 1995 and 1994, respectively), as defined in the Partnership agreement. As of
December 31, 1996, the Company continues to be an equal partner in the
Partnership.

         Payments from Amgen, with respect to its Minimum Annual Funding
obligation, and the Partnership, in connection with services provided to the
Partnership, are recognized as contract research and development revenue as
earned. Such revenue for the years ended December 31, 1996, 1995 and 1994
totaled approximately $5.8 million, $7.8 million, and $8.9 million,
respectively. Contract research and development payments received in advance are
deferred and recognized as revenue when the related services are performed. In
addition, the Amgen Agreement contains a provision whereby the Company will
receive defined amounts ("Research Progress Payments") from Amgen when each
Product reaches certain levels of development. The Company received Research
Progress Payments of $1.0 million in 1994 and 1993 when the respective Products
commenced clinical trials.

         Selected financial data of the Partnership as of December 31, 1996 and
1995 and for the years ended December 31, 1996, 1995 and 1994, are as follows:

         Balance Sheet Data

                                                  1996             1995

                                                  ----             ----
    Cash                                       $14,640,000    $17,498,000
    Accounts payable and accrued expenses
        due to partners  (1)                    12,230,000     14,952,000
    Partners' capital accounts

             Amgen                               1,205,000      1,273,000
             The Company                         1,205,000      1,273,000

(1)  Includes approximately $0.5 million and $0.6 million due the Company at
     December 31, 1996 and 1995, respectively.



                                      F-13

<PAGE>

                  REGENERON PHARMACEUTICALS, INC.
                    NOTES TO FINANCIAL STATEMENTS (Continued)

         Statement of Operations Data

 
                                 1996            1995               1994
                                 ----            ----               ----
     Total revenue             $750,000          $387,000            ---
     Total expenses (2)      29,250,000        30,497,000       $24,588,000
                            -----------        ----------       -----------
     Net loss               $28,500,000       $30,110,000       $24,588,000
                            ===========       ===========       ===========

         (2) Includes approximately $5.8 million, $7.0 million, and $8.9 million
related to services provided by the Company for the years ended December 31,
1996, 1995, and 1994, respectively.

         In 1990, Amgen purchased 767,656 shares of Series D convertible
preferred stock for $15.0 million. Such shares converted into 788,766 shares of
Class A Stock in April 1991 at the time of the Company's initial public
offering. In addition, in 1996, Amgen Inc. purchased from the Company 3 million
shares of Common Stock and 700,000 warrants for $48.0 million. The warrants have
an exercise price of $16 per share, are fully exercisable, expire on April 15,
2001, and are subject to anti-dilution provisions, as defined.

         b.  Sumitomo Pharmaceuticals Company, Ltd.
         In June 1994, the Company entered into a research and development
agreement with Sumitomo Pharmaceuticals Company, Ltd. ("Sumitomo
Pharmaceuticals") to collaborate in the research and development of BDNF in
Japan. Sumitomo Pharmaceuticals paid the Company $13.0 million in June 1994 and
agreed to pay $3.0 million annually on each January 1 from 1995 to 1998
(inclusive) for research payments. Only the 1998 annual payment remains to be
paid. If Sumitomo Pharmaceuticals cancels the 1998 payment, the rights granted
by the Company to Sumitomo Pharmaceuticals to develop and commercialize BDNF in
Japan will revert to the Company. The research payments from Sumitomo
Pharmaceuticals are recognized as contract research and development revenue over

a twelve month period. The Company recognized contract research and development
revenue with respect to research payments of approximately $3.0 million, $8.4
million, and $7.6 million in 1996, 1995 and 1994, respectively. Research
payments from Sumitomo Pharmaceuticals that are received in advance are deferred
and recognized as revenue when the related services are performed. At December
31, 1996 and 1995, there were $3.0 million of such amounts. In addition,
Sumitomo Pharmaceuticals reimburses the Company for its activities in developing
manufacturing processes for BDNF and supplying BDNF and other research materials
to Sumitomo Pharmaceuticals ("manufacturing payments"). Such manufacturing
payments, which are included in contract research and development revenue,
totaled approximately $8.5 million, $7.0 million, and $3.1 million in 1996,
1995, and 1994, respectively.

         In addition, during 1989, Sumitomo Chemical Company, Limited, an
affiliate of Sumitomo Pharmaceuticals, entered into a stock purchase agreement
whereby it purchased, for $4.4 million, 885,062 shares of Class C Preferred
Stock. Such shares converted into 909,401 shares of Class A Stock in April 1991
at the time of the Company's initial public offering.

         c.  Glaxo-Wellcome plc
         During July 1993, the Company entered into a collaborative research
agreement with Glaxo-Wellcome plc ("Glaxo"). Products that are developed by the
joint efforts of Glaxo and the Company will be commercialized by one or more
equally owned joint ventures. Glaxo also purchased 500,000 shares of the
Company's Common Stock at a price of $20 per share.

         d.  Medtronic, Inc.
         During June 1996, the Company and Medtronic, Inc. ("Medtronic") entered
into a worldwide exclusive joint development agreement (the "Medtronic
Agreement") to collaborate on research and development of therapeutics for
central nervous system diseases and disorders using experimental Regeneron
compounds and Medtronic delivery systems. The Medtronic Agreement, among other
things, provides for the Company and Medtronic to fund development costs and
supply amounts of drug and delivery systems, respectively. In addition,
Medtronic is required to make payments to Regeneron if certain clinical
milestones are achieved and the Company is required to pay royalties to
Medtronic based upon net sales of any drug developed under the collaboration.
The Medtronic Agreement may be terminated by written agreement of both parties,
by either party if certain regulatory approvals have not been obtained within
specified time periods, or by either party under certain other conditions.

         In addition, during June, 1996, Medtronic, Inc. purchased from the
Company 460,500 shares of Common Stock and 107,400 warrants for $10.0 million.
The warrants have an exercise price of $21.72 per share, are fully exercisable,
expire on June 26, 2001, and are subject to anti-dilution provisions and other
defined adjustments.


                                      F-14

<PAGE>

                  REGENERON PHARMACEUTICALS, INC.
                    NOTES TO FINANCIAL STATEMENTS (Continued)


         e.  Procter & Gamble Pharmaceuticals, Inc. 
         During December 1996, the Company entered into a collaboration 
agreement with Procter & Gamble Pharmaceuticals, Inc. ("Procter & Gamble")
to jointly discover and develop therapeutics ("compound") for muscle diseases 
and disorders. As part of the agreement, Procter & Gamble agreed to provide, 
for a minimum of three years, minimum annual research funding to the Company 
of $3.75 million. At December 31, 1996, deferred revenue-current portion 
included $0.9 million of prepaid research funding. Procter & Gamble has the 
option to fund additional amounts and has the right to terminate the agreement
after three years. In the event that a compound is discovered and developed to
certain defined levels (but not before the third anniversary of the agreement),
Procter & Gamble and the Company have agreed to negotiate, in good faith, an 
agreement whereby they would jointly complete the development of and 
commercialize the compound.

         In addition, during December 1996, the Company and Procter & Gamble
entered into a Stock Purchase Agreement whereby Procter & Gamble agreed to
purchase $10.0 million of the Company's Common Stock. Procter & Gamble paid
$10.0 million in December 1996 and in March 1997 received 800,000 shares of
restricted Common Stock based on a 27% premium over an average market price over
a period of time.

9.    Manufacturing Agreement

         During September 1995, the Company entered into a long-term
manufacturing agreement with Merck & Co., Inc. (the "Merck Agreement") to
produce an intermediate (the "Intermediate") for a Merck pediatric vaccine at
the Company's Rensselaer, New York facility. The Company has agreed to modify
portions of its facility for manufacture of the Intermediate and to assist Merck
in securing regulatory approval for such manufacture in the Company's facility.
Once the facility is able to produce Intermediate, the Merck Agreement calls for
the Company to manufacture Intermediate for Merck for six years (the "Production
Period"), with certain minimum order quantities each year. The Merck Agreement
is expected to extend into 2003 and may be terminated at any time by Merck upon
the payment by Merck of a termination fee.

         Merck has agreed to reimburse the Company for the capital costs to
modify the facility ("Capital Costs") and for the cost of Company activities
performed on behalf of Merck prior to the Production Period ("Internal Costs").
Merck has also agreed to pay an annual facility fee (the "Facility Fee") of $1.0
million beginning March 1995, subject to annual adjustment for inflation. During
the Production Period, Merck has agreed to reimburse the Company for certain
manufacturing costs and pay the Company a variable fee based on the quantity of
Intermediate supplied to Merck. These payments are recognized as contract
manufacturing revenue as follows: (i) payments for Internal Costs are recognized
as the activities are performed, (ii) the Facility Fee is recognized over the
period to which it relates, (iii) payments for Capital Costs are being deferred
and will be recognized over the Production Period, and (iv) payments related to
the manufacture of Intermediate during the Production Period will be recognized
as Intermediate is accepted by Merck.

         For the years ended December 31, 1996 and 1995, contract manufacturing
revenue includes approximately $1.0 million and $0.8 million of Facility Fee,
respectively, and $1.4 million and $0.3 million of Internal Costs, respectively.

At December 31, 1996, deferred revenue-current portion included $0.2 million of
Facility Fee and deferred revenue-long-term portion included $13.3 million of
Capital Costs. At December 31, 1995, deferred revenue-current portion included
$0.2 million of Facility Fee and deferred revenue-long-term portion included
$6.9 million of Capital Costs.

10.  Incentive and Stock Purchase Plans

         a.  Long-Term Incentive Plan
         During 1990, the Company established the Regeneron Pharmaceuticals,
Inc. 1990 Long-Term Incentive Plan ("Incentive Plan"). The Incentive Plan, as
amended, provides for a maximum of 3,900,000 shares of Common Stock for awards.
Salaried employees who are officers or who are employed in an executive,
administrative, or professional capacity, and nonemployees, including
consultants and members of the Scientific Advisory Board or Board of Directors,
may receive awards as determined by a committee of independent directors
("Committee"). Awards generally vest on a pro rata basis over a three or five
year period and have a term of ten years. The awards under the Incentive Plan
include: (a) Restricted Share Rights, (b) Incentive Stock Rights, (c) Stock
Options, (d) Stock Appreciation Rights, and (e) Performance Unit Rights.

         Restricted Share Rights ("RSR") are awards in which participants in the
Incentive Plan are awarded the right to purchase shares of Common Stock at a
price determined by the Committee. Such shares are nontransferable for a period
determined by the Committee ("vesting period") and, should employment terminate
as defined by the Incentive Plan, the ownership of the shares will be
transferred to the Company in consideration of amounts paid to acquire such
shares. The holder of the RSR has the right to vote and receive dividends during
the vesting period.



                                      F-15

<PAGE>

                  REGENERON PHARMACEUTICALS, INC.
                    NOTES TO FINANCIAL STATEMENTS (Continued)


         Incentive Stock Rights ("ISR") are awards in which participants are
awarded by the Committee the right to receive shares of Common Stock, at no cost
to the participant, in consideration of services performed subject to a vesting
period as determined by the Committee. Holders of ISRs have the right to receive
cash payments from the Company at the same time and in the same amounts as the
holders of Common Stock.

         Stock Options are awards in which participants receive the right to
purchase shares of Common Stock at prices determined by the Committee. The
options vest to the employees over a period of time determined by the Committee.

         Stock Appreciation Rights ("SAR") may be issued by the Committee in
connection with stock options and allow the option holder to receive Common
Stock (or cash if the Board of Directors elects to do so) equal in value to the
difference between the fair market value of the Common Stock at the exercise

date and the stock option price. Should a participant exercise a SAR, an
equivalent number of stock options will be canceled. SARs have a vesting period
similar to that of stock options.

         Performance Unit Rights are awards which the Committee may issue alone
or grant in conjunction with related stock options. Such awards entitle the
holder to receive common stock, cash, or a combination of both at no cost to the
participant upon specific performance objectives being achieved and other
conditions being met, as defined by the Incentive Plan.

         The Incentive Plan contains provision for immediate vesting of awards
upon a change in control of the Company, as defined.

         The Company may incur charges to operations in connection with these
awards.

         Transactions involving stock option awards during 1994, 1995, and 1996
are summarized in the table below. Option exercise prices were equal to the
market price of the Company's common stock on the date of grant. The total
number of options exercisable at December 31, 1994, 1995, and 1996 was 340,428,
635,233, and 943,118, respectively. As of December 31, 1996, shares available
for future grants amounted to 683,149.


<TABLE>
<CAPTION>

                                                              Number  
                                                                of             Range of        Weighted-Average  
                                                              Shares       Exercise Prices      Exercise Price 
                                                              ------       ---------------      -------------- 
<S>                                                       <C>            <C>                    <C>   
Stock options outstanding at December 31, 1993              1,072,993      $8.25 to $21.50              $13.27

1994: Stock options granted  (1)                            1,952,770      $3.63 to $16.38               $5.90
      Stock options canceled  (1)                          (1,016,090)     $4.00 to $21.50              $12.79
                                                          -----------
      Stock options outstanding at December 31,             2,009,673      $3.63 to $18.00               $6.36
      1994

1995: Stock options granted                                   852,744      $3.00 to $16.38               $5.26
      Stock options canceled                                 (117,340)     $3.00 to $12.38               $4.48
      Stock options exercised                                 (73,300)     $4.00 to $12.00               $4.22
                                                          -----------
      Stock options outstanding at December 31,             2,671,777      $3.00 to $18.00               $6.15
      1995

1996: Stock options granted                                   658,827     $12.00 to $23.06              $13.14
      Stock options canceled                                 (198,643)     $3.00 to $15.50              $11.17
      Stock options exercised                                (210,094)     $3.00 to $18.00               $6.46
                                                          -----------
      Stock options outstanding at December 31,             2,921,867      $3.00 to $23.06               $7.36
      1996                                                ===========
</TABLE>




(1)  On July 18, 1994, the Company repriced certain stock options granted under
     the Company's Incentive Plan. A total of 691,080 stock options were
     repriced (the "repriced options"). Certain Company employees who had
     previously been granted stock options under the Incentive Plan received new
     grants which canceled their prior grants and awarded the same number of
     options on the same vesting schedule that governed their original grants at
     an exercise price of $4.00 per share (the fair market value on the date of
     grant). The Company's Vice Presidents received new grants which canceled
     their prior grants and awarded 40% of the number of options previously
     granted on the same vesting schedule that governed their original grants
     and 40% of the number of options previously granted on a five-year vesting
     schedule commencing July 18, 1994, at an exercise price of $4.00 per share
     for all such newly granted options. The following stock option grantees did
     not receive repriced options: the members of the Board of Directors
     (including the President and Chief Executive Officer), employees who were
     included in the reduction in workforce, and nonemployee service providers
     (including but not limited to outside consultants and members of the
     Scientific Advisory Board). The repricing program was determined, in
     accordance with the terms of the Incentive Plan, by the Committee.



                                      F-16

<PAGE>
                         REGENERON PHARMACEUTICALS, INC.
                    NOTES TO FINANCIAL STATEMENTS (Continued)


The following table summarizes stock option information as of December 31, 1996:


<TABLE>
<CAPTION>

                                       Options Outstanding                                   Options Exercisable
                        ------------------------------------------------------  -----------------------------------
                                         Weighted-Average
       Range of             Number          Remaining         Weighted-Average    Number       Weighted-Average
    Exercise Prices      Outstanding     Contractual Life      Exercise Price   Exercisable     Exercise Price
    ---------------      -----------     ----------------      --------------   -----------     --------------
<S>                    <C>                <C>                 <C>               <C>             <C>  
     $3.00 to $4.25      1,503,050               7.6                 $4.01        526,123              $4.07
     $4.38 to $10.25       545,960               7.8                 $6.71        130,392              $7.00
     $10.38 to $15.50      775,075               7.9                $13.00        246,281             $13.29
     $15.56 to $23.06       97,782               7.8                $17.73         40,322             $17.80
                            ------                                                ------
                      
     $3.00 to $23.06     2,921,867               7.7                 $7.36        943,118              $7.47
                         =========                                                =======
</TABLE>


         The following table summarizes the pro forma operating results of the
Company had compensation costs for the Incentive Plan been determined in
accordance with the fair value based method of accounting for stock based

compensation as prescribed by SFAS No. 123. Since option grants awarded during
1996 and 1995 vest over several years and additional awards are expected to be
issued in the future, the pro forma results shown below are not likely to be
representative of the effects on future years of the application of the fair
value based method.

                                            1996               1995
                                            ----               ----

   Pro forma net loss                     ($35,368,272)      ($24,700,788)
                                          =============      =============

   Pro forma net loss per share                ($1.40)          ($1.22)
                                               =======          =======

         For the purpose of the above pro forma calculation, the fair value of
each option granted from the Incentive Plan during 1996 and 1995 was estimated
on the date of grant using the Black-Scholes option pricing model. The
weighted-average fair value of the options granted during 1996 and 1995 was
$13.14 and $5.26, respectively. The following assumptions were used in computing
the fair value of option grants during 1996 and 1995: expected volatility of
85%, expected lives of 3 years after vesting, and zero dividend yield for both
1996 and 1995; risk-free interest rates of 5.46%-6.92% in 1996 and 5.53%-7.15%
in 1995.

         b.  Executive Stock Purchase Plan
         In 1989, the Company adopted an Executive Stock Purchase Plan (the
"Plan") under which 1,027,500 shares of Class A Stock were reserved for
restricted stock awards. The Plan provides for the compensation committee of the
Board of Directors to award employees, directors, consultants, and other
individuals ("Plan participants") who render service to the Company the right to
purchase Class A Stock at a price set by the compensation committee. The Plan
provides for the vesting of shares as determined by the compensation committee
and, should the Company's relationship with a Plan participant terminate before
all shares are vested, unvested shares will be repurchased by the Company at a
price per share equal to the original amount paid by the Plan participant.
During 1989 and 1990, a total of 983,254 shares were issued and as of December
31, 1996, there were 44,246 shares available for future grants under the Plan.

11.  Employee Savings Plan

         The Company, during 1993, adopted the provisions of the Regeneron
Pharmaceuticals, Inc. 401(k) Savings Plan (the "Savings Plan"). The terms of the
Savings Plan provide for employees who have met defined service requirements to
participate in the Savings Plan by electing to contribute to the Savings Plan a
percentage of their compensation to be set aside to pay their future retirement
benefits, as defined. The Savings Plan provides for the Company to make
discretionary contributions, as defined. To date, the Company has made no
contributions to the Savings Plan.



                                      F-17

<PAGE>


                         REGENERON PHARMACEUTICALS, INC.
                    NOTES TO FINANCIAL STATEMENTS (Continued)


12.  Income Taxes

         There is no provision (benefit) for federal or state income taxes,
since the Company has incurred operating losses since inception and has
established a valuation allowance equal to the total deferred tax asset.

         The tax effect of temporary differences, net operating loss
carry-forwards, and research and experimental tax credit carry-forwards as of
December 31, 1996 and 1995 was as follows:

                                                 1996                 1995
                                                 ----                 ----
      Deferred tax assets

       Net operating loss carry-forward          $53,390,000      $46,286,000
       Fixed assets                                2,261,000        1,493,000
       Deferred revenue                            7,957,000        2,867,000
       Research and experimental tax credit 
            carry-forward                          4,501,000        3,849,000
       Other                                       1,265,000          621,000
       Valuation allowance                       (69,374,000)     (55,116,000)
                                                 ------------     ------------
                                                      --                 --
                                                 ============     ============
                                                                    

         As of December 31, 1996, the Company had available for tax purposes
unused net operating loss carry-forwards of approximately $129.0 million which
will expire in various years from 2003 to 2011. The Company's research and
experimental tax credit carry-forwards expire in various years from 2003 to
2011.

13.  Litigation

         In 1995, the Company settled a securities class action lawsuit against
the Company and two individuals. As part of the settlement, the Company issued
153,017 shares of the Company's Common Stock in January 1996. The total cost to
the Company of the settlement, before legal expenses and after reimbursement
from the Company's insurance providers, was approximately $0.9 million.

                                      F-18


<PAGE>                         
                           AMGEN-REGENERON PARTNERS

                             FINANCIAL STATEMENTS

                                       
                         Year ended December 31, 1996
                                     with
                        Report of Independent Auditors



                                     F-19


<PAGE>











                REPORT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS



The Partners
Amgen-Regeneron Partners


We have audited the accompanying balance sheets of Amgen-Regeneron  Partners,  a
Delaware general  partnership, as of December 31, 1996 and 1995, and the
related  statements of operations, changes in partners' capital, and cash
flows for each of the three years in the period ended December 31, 1996. 
These  financial statements are the responsibility of the Partnership's 
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with generally accepted auditing
standards. Those standards require that we plan and perform the audit to obtain
reasonable assurance about whether the financial statements are free of material
misstatement. An audit includes examining, on a test basis, evidence supporting
the amounts and disclosures in the financial statements. An audit also
includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement 
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present 
fairly, in all material respects, the financial position of 
Amgen-Regeneron Partners at December 31, 1996 and 1995, and the results of its
operations and its cash flows for each of the three years in the period 
ended December 31, 1996, in conformity with generally accepted accounting
principles.


ERNST & YOUNG LLP

Los Angeles, California
February 5, 1997


                                     F-20


<PAGE>

                           AMGEN-REGENERON PARTNERS

                                BALANCE SHEETS

                          December 31, 1996 and 1995

                                (In thousands)

<TABLE>
<CAPTION>
                                                                                       1996             1995 
                                                                                     -------          -------
<S>                                                                                <C>             <C>         
                                   ASSETS

Total current assets - cash and cash equivalents...........................          $14,640          $17,498
                                                                                     =======          =======

                      LIABILITIES AND PARTNERS' CAPITAL

Total current liabilities - accounts payable and accrued expenses 
   due to partners                                                                   $12,230          $14,952
                                                                                     -------          -------
Partners' capital:
     Capital Accounts A:
         Amgen    .........................................................            1,205            1,273
         Regeneron.........................................................            1,205            1,273
     Capital Account B - Amgen.............................................                -                -
                                                                                     -------          -------
              Total partners' capital......................................            2,410            2,546
                                                                                     -------          -------

                  Total liabilities and partners' capital..................          $14,640          $17,498
                                                                                     =======          =======
</TABLE>



                            See accompanying notes.

                                     F-21


<PAGE>

                                             AMGEN-REGENERON PARTNERS

                                             STATEMENTS OF OPERATIONS

                                   Years ended December 31, 1996, 1995 and 1994

                                                  (In thousands)


<TABLE>
<CAPTION>

                                                                       1996             1995             1994  
                                                                   --------          --------         --------
<S>                                                               <C>              <C>           <C>  
Revenues:
     Interest income......................................        $     750        $      387    $           -
                                                                   --------          --------         --------
         Total revenues...................................              750               387                -
                                                                   --------          --------         --------

Expenses:
     Research and development performed
         by partners......................................           29,069            30,363           24,484
     General and administrative...........................              181               134              104
                                                                   --------          --------         --------

         Total expenses...................................           29,250            30,497           24,588
                                                                   --------          --------         --------

Net loss..................................................        $ (28,500)        $ (30,110)       $ (24,588)
                                                                   ========          ========         ========
</TABLE>







                            See accompanying notes.

                                     F-22


<PAGE>

                                             AMGEN-REGENERON PARTNERS

                                    STATEMENTS OF CHANGES IN PARTNERS' CAPITAL

                                   Years ended December 31, 1996, 1995 and 1994

                                                  (In thousands)



<TABLE>
<CAPTION>
                                                       Amgen Capital                Regeneron Capital
                                                 -------------------------          -----------------
                                                 Account A       Account B              Account A
                                                 ---------       ---------              ----------
<S>                                              <C>            <C>                     <C>
Balance at December 31, 1993.................    $     232      $         -             $      232

Capital contributions........................       11,218           5,000                  11,218

Net loss                                            (9,794)         (5,000)                 (9,794)
                                                 ---------       ---------              ----------
Balance at December 31, 1994.................        1,656               -                   1,656

Capital contributions........................       13,422           2,500                  13,422

Net loss                                           (13,805)         (2,500)                (13,805)
                                                 ---------       ---------              ----------
Balance at December 31, 1995.................        1,273               -                   1,273

Capital contributions........................       14,182               -                  14,182

Net loss                                           (14,250)              -                 (14,250)
                                                 ---------       ---------              ----------
Balance at December 31, 1996.................    $   1,205      $        -              $    1,205
                                                 =========       =========              ==========
</TABLE>


                            See accompanying notes.

                                     F-23


<PAGE>

                                             AMGEN-REGENERON PARTNERS

                                             STATEMENTS OF CASH FLOWS

                                   Years ended December 31, 1996, 1995 and 1994

                                                  (In thousands)

<TABLE>
<CAPTION>
                                                                       1996               1995                1994  
                                                                   ---------            --------            --------
<S>                                                                <C>                  <C>                 <C>
Cash flows from operating activities:
     Net loss                                                       $(28,500)           $(30,110)           $(24,588)
     (Decrease) increase in accounts payable and ...........
        accrued expenses                                              (2,722)              7,895               4,158
                                                                   ---------            --------            --------
              Net cash used in operating activities.........         (31,222)            (22,215)            (20,430)

Cash flows from financing activities - capital contributions
                                                                      28,364              29,344              27,436
                                                                   ---------            --------            --------
(Decrease) increase in cash and cash equivalents............          (2,858)              7,129               7,006

Cash and cash equivalents at beginning of period............          17,498              10,369               3,363
                                                                   ---------            --------            --------

Cash and cash equivalents at end of period..................        $ 14,640            $ 17,498            $ 10,369
                                                                   =========            ========            ========
</TABLE>


                                       
                            See accompanying notes.

                                     F-24



<PAGE>
                           AMGEN-REGENERON PARTNERS
                                       
                         NOTES TO FINANCIAL STATEMENTS
                                       
                               December 31, 1996


1.       Summary of significant accounting policies

     Business and organization

     Amgen-Regeneron Partners (the "Partnership"), a general partnership, was
formed on June 21, 1991, under the laws of the State of Delaware between Amgen
Inc. ("Amgen") and Regeneron Pharmaceuticals, Inc. ("Regeneron"). The
Partnership was formed to develop and commercialize in the United States BDNF
and NT-3 ("Products") for human pharmaceutical use, in conformity with a
Collaboration Agreement (Note 3).

     Under the Collaboration Agreement, Amgen will be primarily responsible for
the manufacture and commercialization of the Products in the United States, if
successfully developed by the Partnership. Amgen's costs in connection with such
activities will be reimbursed at agreed to rates. Unless terminated earlier, the
Partnership will continue in effect, with respect to each Product, until the
later of the expiration of the last United States patent of each Product, or
fifteen years from the date on which each Product was approved for sale in the
United States.

     A Joint Management Committee (the "Committee") is responsible for the
overall management of the business and affairs of the Partnership as well as
activities performed under the Collaboration Agreement. Each partner has
appointed three representatives to the Committee. One additional representative
may be appointed by a partner if the balance of their Capital Account A becomes
more than twice the amount of the balance of the other partner's Capital Account
A (Note 2).

     Cash equivalents

     The Partnership considers only those investments which are highly liquid,
readily convertible to cash and which mature within three months of the date of
purchase as cash equivalents. At December 31, 1996 and 1995, cash and cash
equivalents consisted of a single interest bearing money market account.

     Research and development

         Research and development costs are expensed as incurred.

     Income taxes

     The Partnership's financial statements do not include a provision (credit)
for income taxes. Income taxes, if any, are the liability of the individual
partners.

     Use of estimates


     The preparation of financial statements in conformity with generally
accepted accounting principles requires management to make estimates and
assumptions that affect the amounts reported in the financial statements and
accompanying notes. Actual results could differ from those estimates.

                                     F-25


<PAGE>

                           AMGEN-REGENERON PARTNERS
                                       
                   NOTES TO FINANCIAL STATEMENTS (Continued)

     Reclassifications

     Certain prior year amounts have been reclassified to conform to the current
year presentation.


2. Capital contributions, allocation of profits and losses and cash
   distributions

     Capital contributions are recorded in the Capital Account A of each
partner, except for contributions related to the product development funding
obligation, discussed below. Capital Account A contributions are generally made
quarterly in advance based upon capital calls made by the Committee pursuant to
projected cash requirements of the Partnership. Cash distributions and profits
or losses, except for that portion due to expenses related to the product
development funding obligation, are allocated to each partner in proportion to
their respective Capital Account A contributions.

     Pursuant to Amgen's product development funding obligation to Regeneron
under the Collaboration Agreement (Note 3), Amgen made stated quarterly cash
contributions to the Partnership which were credited to Amgen's Capital Account
B. Such funds were then used to satisfy the Partnership's obligation to
Regeneron for performing specified research and development activities on behalf
of the Partnership. The expenses related to such activities were allocated to
Amgen's Capital Account B.


3. Collaboration Agreement

     In August 1990, Amgen and Regeneron entered into a Collaboration Agreement
to develop and commercialize BDNF and NT-3, compounds for which Regeneron
possesses substantial scientific, technical and proprietary information. Each
party has agreed to perform research and development on the Products under
product development programs approved by the Committee. Upon Amgen's
notification in writing to Regeneron that the preparation of an Investigational
New Drug Application for each Product should commence, the licenses granted by
the partners to the Partnership for the underlying technologies, discussed
below, became effective on a Product-by-Product basis. Also, upon such
notification, further research and development of the Products under the
licenses became the obligation of the Partnership. These licenses grant the

Partnership an exclusive, royalty-free right to develop, make, have made, use,
and sell, and distribute each Product for human pharmaceutical use in the United
States. The Partnership has, in turn, granted to Amgen and Regeneron exclusive,
royalty-free sublicenses for the underlying technologies to the extent necessary
to fulfill their obligations under the Collaboration Agreement. These
sublicenses became effective at the same time the related licenses granted the
Partnership became effective.

     Pursuant to the terms of the Collaboration Agreement, Amgen and Regeneron
conduct certain research and development activities on behalf of the
Partnership, including contracting with third parties to conduct clinical
trials. Amgen also provides on behalf of the Partnership certain quantities of
materials, primarily for clinical testing. Amgen and Regeneron are paid for such
services and materials at amounts approved by the Committee. During the years
ended December 31, 1996, 1995 and 1994, the Partnership incurred expenses
(including accrued expenses) of $23,191,000, $23,392,000 and $15,604,000
respectively, from Amgen and $5,878,000, 

                                     F-26


<PAGE>

                           AMGEN-REGENERON PARTNERS
                                       
                   NOTES TO FINANCIAL STATEMENTS (Continued)

$4,471,000 and $3,880,000 respectively, from Regeneron for such services and
materials. These amounts are included in research and development expense in the
accompanying statements of operations. In addition, certain other costs
associated with the development of the Products have been incurred by the
partners but not charged to the Partnership or reflected in the accompanying
financial statements. At December 31, 1996, accounts payable and accrued
expenses due to partners was composed of $7,307,000 of accounts payable and
$4,451,000 of accrued clinical costs due to Amgen and $472,000 of accounts
payable due to Regeneron. At December 31, 1995, accounts payable and accrued
expenses due to partners was composed of $7,944,000 of accounts payable and
$6,364,000 of accrued clinical costs due to Amgen and $644,000 of accounts
payable due to Regeneron.

     The Collaboration Agreement obligated Amgen to fund a portion of the
product development costs incurred by Regeneron at specified rates. This funding
obligation of $2,500,000 per year for each Product terminated in August 1995.
Payments were due quarterly in advance. The related amounts for each Product
were paid by Amgen directly to Regeneron until the licenses with respect to the
Products became effective. Thereafter, Amgen contributed such amounts to the
Partnership, and the Partnership remitted the amounts to Regeneron in
consideration of certain research and development activities performed by
Regeneron on behalf of the Partnership. Research and development expense for the
years ended December 31, 1995 and 1994 included $2,500,000 and $5,000,000
respectively, of costs incurred under this funding obligation.


4.       Subsequent event (unaudited)


     On January 10, 1997, Amgen and Regeneron announced the Phase 3 clinical
trial of BDNF did not demonstrate clinical efficacy in patients with amyotrophic
lateral sclerosis (ALS), commonly known as Lou Gehrig's Disease and that no
further development of subcutaneous delivery for ALS is planned. The trial was
designed to evaluate the effects of subcutaneous delivery of BDNF for ALS. A
small, early-stage clinical trial investigating intrathecal administration of
BDNF for ALS, sponsored by Amgen on behalf of the Partnership, is in progress
and will continue.


                                     F-27







                                                                   EXHIBIT 10.29

                         REGENERON PHARMACEUTICALS, INC.
                            STOCK PURCHASE AGREEMENT

         This Agreement, is made as of December 11, 1996, by and between
Regeneron Pharmaceuticals, Inc., a corporation organized under the laws of New
York (the "Company"), with its principal office at 777 Old Saw Mill River Road,
Tarrytown, New York 10591, and Procter & Gamble Pharmaceuticals, Inc., a
corporation organized under the laws of Ohio (the "Buyer"), with its principal
office at One Procter & Gamble Plaza, Cincinnati, Ohio 45202.

                                    ARTICLE I

                         ISSUANCE AND SALE OF SECURITIES

                  1.1 Issuance and Sale of Securities. Upon the terms set forth
herein, the Company will issue and sell to Buyer, and Buyer will purchase from
the Company, shares of common stock, par value $.001 per share, of the Company
("Common Stock") in an amount to be determined as set forth in Section 2.2 (the
"Shares") for an aggregate price of $10.0 Million in immediately available funds
(the "Securities Purchase Price").

                                   ARTICLE II

                                     CLOSING

                  2.1 Closing. The closing of the sale and purchase of the
Shares under this Agreement (the "Closing") shall take place in two phases: (i)
at 4:00 p.m. New York time on December 11, 1996 ("Closing I") simultaneously at
the offices of the Company and Buyer or at such other time and place as the
parties
 may agree, and (ii) at 10:00 a.m. New York time on June 30, 1997, or at
10:00 a.m. on such earlier business day to be specified by the Buyer upon not
less than forty-five (45) trading days' written notice ("Closing II") at the
offices of the Company or at such other time and place as the parties may agree.

                  2.2 Shares to be Delivered. At Closing II, the Company shall
deliver to Buyer a number of shares of Common Stock rounded up to the next whole
share, equal to the quotient of $7.9 Million divided by the Current Market
Price. Current Market Price is the average of the Quoted Prices of the Common
Stock for thirty (30) consecutive trading days commencing forty five (45)
trading days before Closing II ending the trading day before Closing II. The
"Quoted Price" of the Common Stock is the last reported sales price of the
Common Stock as reported by Nasdaq National Market, or if the Common Stock is
listed on a national 


<PAGE>

securities exchange, the last reported sales price of the
Common Stock on such exchange (which shall be for consolidated trading if
applicable to such exchange), or if neither so reported or listed, the last
reported bid price of the Common Stock. In the absence of one or more such

quotations, the Board of Directors of Regeneron shall determine the Current
Market Price on the basis of such quotation as it in good faith considers
appropriate.

                  2.3 Documents to be Delivered. At Closing I, the Company shall
deliver to Buyer, against payment in full of the Securities Purchase Price, (i)
each of the Collateral Agreements, (the Stock Registration Agreement and the
Collaboration Agreement) which shall have been duly authorized, executed and
delivered by the Company and shall be in full force and effect and (ii) an
opinion of Paul Lubetkin, General Counsel to the Company, in form and substance
reasonably satisfactory to Buyer, substantially to the effect specified in
Sections 3.1 through 3.5, with such exceptions and qualifications as are
customary and reasonable under the law of the applicable jurisdiction. In
rendering such opinion, such counsel may rely upon certificates of public
officers and, as to matters of fact, upon certificates of duly authorized
representatives of the Company, provided, that copies of such certificates shall
be contemporaneously delivered to Buyer. At Closing II, the Company shall
deliver to Buyer (i) a certificate for the Shares dated the date thereof and
registered in the name of Buyer and (ii) an opinion of Paul Lubetkin confirming
or updating his opinion delivered at Closing I.

                                   ARTICLE III

                  REPRESENTATIONS AND WARRANTIES OF THE COMPANY

                  The Company hereby represents and warrants to Buyer as of the
date hereof as follows:

                  3.1 Organization and Standing. The Company has been duly
incorporated and is validly existing and in good standing under the laws of the
State of New York with the corporate power and corporate authority to own and
lease its property, to conduct its business as presently conducted and proposed
to be conducted by it in the manner described in the Company SEC Reports and to
execute and deliver the Agreement and each of the Collateral Agreements. The
Company has corporate power and authority to perform and to carry out the
transaction contemplated by the Agreement and each of the Collateral Agreements.
The Company is qualified to do business and is in good standing in New York.

                  3.2 Capitalization. As of September 30, 1996, the authorized
capital stock of the Company consisted of the following: (a) 60,000,000 shares
of Common Stock, of which (i) 20,855,186 shares were issued and outstanding,
(ii) 4,760,684 shares were reserved for future issuance upon conversion of the
Class A Common Stock, each share of the Class A Stock being convertible into one
share of Company Common Stock, (iii) 3,664,316 shares were reserved for future
issuance under the Company's 1990 Amended and Restated Long-Term Incentive Plan,



<PAGE>
and (iv) 807,400 shares were reserved for future issuance in accordance with
certain warrants issued to Amgen Inc. and Medtronic, Inc.; and (b) 40,000,000
shares of Class A Common Stock, of which 4,760,684 were issued and outstanding
and 17,073 shares were held in treasury; and (c) 30,000,000 shares of Preferred
Stock, (i) none of which were issued and outstanding, and (ii) 100,000 shares of
which are reserved for issuance as Series A Junior Participating Preferred Stock

in accordance with the Rights Agreement dated as of September 20, 1996. No
material change in such capitalization has occurred between September 30, 1996
and the date hereof, and there has been no reduction whatsoever in the number of
shares of any class of the Company's outstanding capital stock. All of the
issued and outstanding shares of Common Stock, Class A Stock, and Preferred
Stock have been duly authorized, and all of the issued and outstanding shares of
the Common Stock and the Class A Common Stock are validly issued and are fully
paid and non-assessable. Except as set forth in the Company SEC Reports or as
provided in the Agreement, there is not, nor upon the consummation of the
transaction- contemplated therein, will there be (i) any subscription, warrant,
option, convertible security, or any other right (contingent or otherwise) to
purchase or acquire any shares of the capital stock of the Company, (ii) any
commitment of the Company to issue any subscription, warrant, option,
convertible security, or other such right or to issue or distribute to holders
of any share of its capital stock any evidence of indebtedness or assets of the
Company, or (iii) any obligation of the Company (contingent or otherwise) to
purchase, redeem or otherwise acquire any shares of its capital stock or any
interest therein or to pay any dividend or make any other distribution in
respect thereof. Except as set forth in the Company SEC Reports or as provided
in the Agreement, no person is entitled to, nor upon the consummation of the
transactions contemplated thereby will any person be entitled to (i) any
preemptive or similar right with respect to the issuance of any capital stock of
the Company, or (ii) any rights with respect to the registration of any capital
stock of the Company under the Securities Act.

                  3.3 Issuance of Shares. The issuance, sale and delivery of the
Shares under the Agreement have been duly authorized and reserved for issuance
by all necessary corporate action on the part of the Company (no consent or
approval of the shareholders of the Company being required by law, by the
Restated Certificate of Incorporation or Bylaws of the Company, or the
qualification criteria of the Nasdaq National Market), and the Shares so issued,
sold, and delivered against payment therefor in accordance with the provisions
of this Agreement will be duly and validly issued, fully paid, and
non-assessable and not subject to preemptive or any other similar rights of the
shareholders of the Company or others and free, at time of issuance of all
restrictions on transfer subject to restrictions on transfer imposed by
applicable federal and state securities laws.

                  3.4 Authority for Agreement. The execution, delivery and
performance by the Company of this Agreement and each of the Collateral
Agreements have been duly authorized by all necessary corporate action, and this
Agreement and each of the Collateral Agreements have been duly executed and
delivered and constitute valid and binding obligations of the Company
enforceable in accordance with their respective terms, subject to bankruptcy or
equitable laws that might affect the enforceability of this Agreement and each
of the Collateral 


<PAGE>

Agreements.  The execution and delivery by the Company of this Agreement and
each of the Collateral Agreements, and the consummation by the Company of the
transactions contemplated hereby and thereby (including, without limitation, the
issuance and sale of the Shares, will not violate any provision of law and will
not conflict with or result in any breach of any of the terms, conditions or

provisions of, or constitute a default under, or result in the creation of any
lien, security interest, charge or encumbrance upon any of the properties,
assets or outstanding capital stock of the Company, under the Company's Restated
Certificate of Incorporation, or Bylaws, or any indenture, lease, agreement or
other instrument to which the Company is a party or by which it or any of its
properties is bound, or any decree, judgment, order, statute, rule or regulation
applicable to the Company.

                  3.5 Governmental Consents. No consent, approval, order or
authorization of, or registration, qualification, designation, declaration or
filing with, any governmental or regulatory authority is required on the part of
the Company in connection with the execution and delivery of this Agreement and
each of the Collateral Agreements, and the consummation of the transactions
contemplated hereby and thereby (including, without limitation, the offer,
issue, sale and delivery of the Shares), except such filings as shall have been
made or consents or approvals obtained prior to and which shall be effective on
and as of the Closing.

         Based in part on the representations made by Buyer in Article IV of
this Agreement, the offer and sale of the Shares to Buyer will be in compliance
with applicable federal and state securities laws.

                  3.6 Litigation. Except as set forth in the Company SEC
Reports, there are no material actions, suits, proceedings or investigations,
either at law or in equity, or before any commission or other administrative
authority in any United States or foreign jurisdiction, of any kind now pending
or, to the best of the Company's knowledge, threatened or proposed involving the
Company or any of its properties or assets or which questions the validity or
legality of the transactions contemplated hereby, or to the Company's actual
knowledge, against its employees or consultants with respect to the Company's
business.

                  3.7      SEC Filings; Financial Statements.

                  (a) The Company has filed all forms, reports and documents
required to be filed with the Securities and Exchange Commission (the
"Commission") since May 3, 1993 (collectively, the "Company SEC Reports"). The
Company SEC Reports (i) were prepared in all material respects in accordance
with the requirements of the Securities Act of 1933 (the "Securities Act") or
the Securities Exchange Act of 1934 (the "Exchange Act"), as the case may be,
and (ii) did not at the time they were filed (or if amended or superseded by a
filing prior to the date of this Agreement, then on the date of such filing)
contain any untrue statement of a material fact or omit to state a material fact
required to be stated therein or necessary in order to make the statements
therein, in the light of the circumstances under which they were made, not
misleading.


<PAGE>

                  (b) Each of the financial statements (including, in each case,
any related notes thereto) contained in the Company SEC Reports was prepared in
accordance with generally accepted accounting principles applied on a consistent
basis throughout the periods involved (except as may be indicated in the notes
thereto), and each was complete and correct in all material respects and

presented fairly in all material respects presented the financial position of
the Company as at the respective dates thereof and the results of its operations
and cash flows for the periods indicated, except that the unaudited interim
financial statements were or are subject to normal and recurring year-end
adjustments which were not or are not expected to be material in amount.

                  3.8 No Undisclosed Liabilities. The Company does not have any
material liabilities (absolute, accrued, contingent or otherwise) except
liabilities (a) in the aggregate adequately provided for in the Company's
unaudited balance sheet (including any related notes thereto) for the quarter
ended September 30, 1996 included in the Company's Quarterly Report on Form 10-Q
for the quarter year ended September 30, 1996 (the "September 30, 1996 Balance
Sheet"), or (b) incurred since September 30, 1996 in the ordinary course of
business.

                  3.9 Absence of Changes. Since September 30, 1996, there has
been no material adverse change in the financial condition, business, or assets
of the company.

                  3.10     Intellectual Property.

                  (a) To the best of the Company's knowledge, it has done
nothing to compromise the secrecy, confidentiality or value of any of its trade
secrets, know-how, inventions, prototypes, designs, processes or technical data
required to conduct its business as now conducted or as proposed to be
conducted. The Company will continue to take reasonable security measures in the
future, as it presently is doing, to protect the secrecy, confidentiality, and
value of all of its trade secrets, know-how, inventions, prototypes, designs,
processes, and technical data import to the conduct of its business.

                  (b) Except as set forth in the Company SEC Reports or as
otherwise disclosed to Buyer, the Company has not granted rights to manufacture,
produce, license, market or sell its products to any other Person and is not
bound by any agreement that affects the Company's exclusive right to develop,
manufacture, distribute, market or sell its products.

                  3.11 No Defaults. The Company is not in default (a) under its
Restated Certificate of Incorporation or Bylaws, each as amended or restated to
date, or any indenture, mortgage, lease agreement, contract, purchase order or
other instrument to which it is a party or by which it or any of its property is
bound or affected or (b) with respect to any order, writ, injunction or decree
of any court of any federal, state, municipal or other governmental department,
commission, board, bureau, agency or instrumentality, domestic or foreign, which
defaults, either singly or in the aggregate, would have a material adverse
effect on the Company. 


<PAGE>

At the time of the Closing, to the best knowledge of the Company, there will
exist no condition, event or act which constitutes, or which after notice, lapse
of time or both would constitute, a material default under any of the foregoing
which, either singly or in the aggregate, would have a material adverse effect
on the Company.


                  3.12 Offerings. Except as contemplated by this Agreement or
the Company's 1990 Amended and Restated Long-Term Incentive Plan or as otherwise
disclosed by the Company to Buyer, the Company does not have any current plans
or intentions to issue any shares of its capital stock or any other securities
or any securities convertible or exchangeable into shares of its capital stock
or any other securities.

                  3.13 Brokers. No broker, finder or investment banker is
entitled to any brokerage, finder's or other fee or commission in connection
with the transactions contemplated by this Agreement based upon arrangements
made by or on behalf of the Company.

                                   ARTICLE IV

                   REPRESENTATIONS AND WARRANTIES OF THE BUYER

                  Buyer hereby represents and warrants to the Company as
follows:

                  4.1 Legal Power. Buyer has the requisite legal power to enter
into this Agreement, the Collaboration Agreement, and the Registration Rights
Agreement to purchase the Shares hereunder, and to carry out and perform its
obligations under the terms of this Agreement, the Collaboration Agreement, and
the Registration Rights Agreement.

                  4.2 Due Execution. This Agreement, the Collaboration Agreement
and the Registration Rights Agreement, have been duly authorized, executed and
delivered by Buyer, and, upon due execution and delivery by the Company, this
Agreement, the Collaboration Agreement, and the Registration Rights Agreement
will be valid and binding agreements on Buyer enforceable in accordance with its
terms, subject to laws of general application relating to bankruptcy, insolvency
and the relief of debtors and rules of law governing specific performance,
injunctive relief or other equitable remedies.

                  4.3      Investment Representations.

                  (a) Buyer is acquiring the Shares for its own account, not as
nominee or agent, for investment and not with a view to, or for resale in
connection with, any distribution or public offering thereof within the meaning
of the 1933 Act.

                  (b) Buyer understands that (i) the Shares have not been
registered under the Securities Act by reason of a specific exemption therefrom,
that they must be held by it 


<PAGE>
indefinitely, and that it must, therefore, bear the economic risk of such
investment indefinitely, unless a subsequent disposition thereof is registered
under the Securities Act or is exempt from such registration; and (ii) each
certificate representing the Shares will be endorsed with the restrictive legend
set forth in the Registration Rights Agreement.

                  (c) Buyer is aware of the provisions of Rule 144 promulgated
under the Securities Act which permits limited resale of shares purchased in a

private placement (i) by non-affiliates of a company not less than three (3)
years after such non-affiliate had purchased and paid for the security to be
sold, or (ii) subject to the satisfaction of certain conditions, including,
among other things, the existence of a public market for the shares, the
availability of certain current public information about the Company, the resale
occurring not less than two (2) years after a party has purchased and paid for
the security to be sold, the sale being through a "broker's transaction" or in
transactions directly with a "market maker" (as provided by Rule 144(f)) and the
number of shares being sold during any three-month period not exceeding
specified limitations.

                  4.4 Brokerage. There are no claims for brokerage commissions,
finders fees or similar compensation tin connection with the transactions
contemplated by this Agreement based on any arrangement or agreement made by or
on behalf of Buyer.

                                    ARTICLE V

                         CONDITIONS TO CLOSING OF BUYER

                  Buyer's obligation to purchase the Shares at the Closing is
subject to the fulfillment to Buyer's satisfaction, at or prior to the Closing,
of all of the following conditions, any of which may be waived by Buyer:

                  5.1 Representations and Warranties True: Performance of
Obligations. The representations and warranties made by the Company in Section 3
hereof shall be true and correct on the date of the Closing with the same force
and effect as if they had been made on and as of said date; and the business and
assets of the Company shall not have been adversely affected in any material way
prior to the Closing.

                  5.2 Covenants. All covenants, agreements and conditions
contained in this Agreement to be performed by the Company on or prior to the
Closing Date shall have been performed or complied with.

                  5.3 Collaboration Agreement and Registration Rights Agreement.
The Company and Buyer shall have entered into a Collaboration Agreement
substantially in the form of Exhibit A hereto and a Registration Rights
Agreement substantially in the form of Exhibit B hereto.


<PAGE>

                  5.4 Opinion of the Company's Counsel. Buyer shall have
received from Paul Lubetkin, General Counsel to the Company, an opinion letter
substantially in the form attached hereto as Exhibit C, addressed to it, dated
the date of the Closing. In rendering the opinion called for under this
paragraph 5.4, counsel may rely as to factual matters on certificates of public
officials, officers of the Company, and officers of Buyer.

                  5.5 Proceedings and Documents. All corporate and other
proceedings in connection with the transactions contemplated at the Closing
hereby and all documents and instruments incident to such transactions shall
have been reasonably approved by Buyer and Buyer shall have received all such
counterpart originals or certified or other copies of such documents as it may

reasonably request.

                  5.6 Qualifications, Legal Investment. All authorizations,
approvals or permits, if any, of any governmental authority or regulatory body
of the United States or of any state that are required in connection with the
lawful sale and issuance of the Shares pursuant to this Agreement, including but
no limited to the Commissioner of Corporations of the Sate of New York, shall
have been duly obtained and shall be effective on and as of the Closing. At the
time of the Closing, the sale and issuance of the shares shall be legally
permitted by all laws and regulations to which Buyer and the Company are
subject.

                                   ARTICLE VI

                      CONDITIONS TO CLOSING OF THE COMPANY

                  The Company's obligations to issue and sell the Shares at the
Closing is subject to the fulfillment to the Company's satisfaction, on or prior
to the Closing, of the following conditions, any of which may be waived by the
Company:

                  6.1 Representations and Warranties True. The representations
and warranties made by Buyer in Section 4 hereof shall be true and correct on
the date of the Closing, with the same force and effect as if they had been made
on and as of said date.

                  6.2 Performance of Obligations. Buyer shall have performed and
complied with all agreements and conditions herein required to be performed or
complied with by it on or before the Closing.

                  6.3 Qualifications, Legal Investment. All authorizations,
approvals or permits, if any, of any governmental authority or regulatory body
of the United States or of any state that are required to be obtained prior to
or at Closing in connection with the lawful sale and issuance of the Shares
pursuant to this Agreement shall have been duly obtained and shall be effective
on and as of the Closing. At the time of the Closing, the sale and issuance of
the Shares 


<PAGE>
shall be legally permitted by all laws and regulations to which Buyer and the
Company are subject.

                  6.4 Collaboration Agreement and Registration Rights Agreement.
The Company and Buyer shall have entered into a Collaboration Agreement
substantially in the form of Exhibit A hereto and a Registration Rights
Agreement substantially in the form of Exhibit B hereto.

                                   ARTICLE VII

                                  MISCELLANEOUS

                  7.1 Governing Law.  This Agreement shall be governed by and 
construed under the laws of the State of New York.


                  7.2 Survival. The representations, warranties, covenants and
agreements made herein shall survive the Closing for the period prescribed by
the applicable statute of limitations. All statements as to factual matters
contained in any certificate or other instrument delivered by or on behalf of
the Company pursuant hereto or in connection with the transactions contemplated
hereby shall be deemed to be representations and warranties by the Company
hereunder as of the date of such certificate or instrument.

                  7.3 Successors and Assigns. Except as otherwise expressly
provided herein, the provisions hereof shall inure to the benefit or, and be
binding upon, the successors, assigns, heirs, executors and administrators of
the parties hereto.

                  7.4 Entire Agreement.This Agreement, the Exhibits hereto, and
the other documents delivered pursuant hereto constitute the full and entire
understanding and agreement along the parties with regard to the subjects hereof
and no party shall be liable or bound to any other party in any manner by any
representations, warranties, covenants or agreements except as specifically set
forth herein or therein. Nothing in this Agreement, express or implied, is
intended to confer upon any party, other than the parities hereto and their
respective successors and assigns, any rights, remedies, obligations or
liabilities under or by reason of this Agreement, except as expressly provided
herein.

                  7.5 Separability. In case any provision of this Agreement
shall be invalid, illegal or unenforceable, it shall to the extent practicable,
be modified so as to make it valid, legal and enforceable and to retain as
nearly as practicable the intent of the parties, and the validity, legality and
enforceability of the remaining provisions shall not in any way be affected or
impaired thereby.


<PAGE>

                  7.6 Amendment and Waiver. Any term of this Agreement may be
amended and the observance of any term of this Agreement may be waived (either
generally or in a particular instance, either retroactively or prospectively,
and either for a specified period of time or indefinitely), only with the
written consent of the Company and Buyer.

                  7.7 Delays or Omissions. No reasonable delay or omission to
exercise any right, power or remedy accruing to Buyer upon any breach, default
or noncompliance of the Company under this Agreement shall impair any such
right, power or remedy, nor shall it be construed to be a waiver of any such
breach, default or noncompliance, or any acquiescence therein, or of any similar
breach, default or noncompliance thereafter occurring. It is further agreed that
any waiver, permit, consent or approval of any kind or character on Buyer's part
of any breach, default or noncompliance under this Agreement or any waiver on
Buyer's part of any provisions or conditions of this Agreement must be in
writing and shall be effective only to the extent specifically set forth in such
writing, and that all remedies, either under this Agreement, by law, or
otherwise afforded to buyer, shall be cumulative and not alternative.

                  7.8 Notices, etc. Any notices or communications provided for
in this Agreement to be made by either of the Parties to the other shall be in

writing, in English, and shall be made by prepaid air mail with return receipt
addressed to the other at its address set forth below. Any such notice or
communication may also be given by hand or facsimile to the appropriate
designation with confirmation of receipt. Either Party may by like notice
specify an address to which notices and communications shall thereafter be sent.
Notices sent by mail shall be effective upon receipt; notices given by hand
shall be effective when delivered.

                  Notices for Regeneron shall be sent to:

                           Regeneron Pharmaceuticals, Inc.
                           Attn:  Corporate Secretary
                           777 Old Saw Mill River Road
                           Tarrytown, New York  10591-6707

                  With copy to:

                           Regeneron Pharmaceuticals, Inc.
                           Attn:  General Counsel
                           777 Old Saw Mill River Road
                           Tarrytown, New York  10591-6707

                  Notices for Procter & Gamble shall be sent to:

                           Procter & Gamble Pharmaceuticals, Inc.
                           Attn:  President
                           One Procter & Gamble Plaza


<PAGE>
                           Cincinnati, Ohio  45202

                  With copy to:

                           Procter & Gamble Pharmaceuticals, Inc.
                           Attn:  Associate General Counsel
                           Blue Ash Office Center
                           10200 Alliance Road
                           Cincinnati, Ohio  45242-4716

                  7.9      Titles and Subtitles.  The titles of the paragraphs
and subparagraphs of this Agreement are for convenience of reference only and
are not to be considered in construing this Agreement.




<PAGE>


                  7.10 Counterparts. This Agreement may be executed in any
number of counterparts, each of which shall be deemed an original, but all of
which together shall constitute one instrument. The foregoing Agreement is
hereby executed as of the date first above written.

REGENERON PHARMACEUTICALS, INC.             PROCTER & GAMBLE
                                            PHARMACEUTICALS, INC.

By: /s/ Leonard S. Schleifer, M.D., Ph.D.   By: /s/ G. Gilbert Cloyd
   ______________________________________      _____________________________
   Leonard S. Schleifer, M.D., Ph.D.           G. Gilbert Cloyd
     President and Chief Executive Officer       President






                                                      
                                                                   EXHIBIT 10.30

                          REGISTRATION RIGHTS AGREEMENT

                                     between

                         REGENERON PHARMACEUTICALS, INC.

                   and PROCTER & GAMBLE PHARMACEUTICALS, INC.

                                December 11, 1996



<PAGE>


                          REGISTRATION RIGHTS AGREEMENT

                  REGISTRATION RIGHTS AGREEMENT, dated as of December 11, 1996,
between Regeneron Pharmaceuticals, Inc., a New York corporation (the "Company"),
and Procter & Gamble Pharmaceuticals, Inc., an Ohio corporation (the
"Purchaser").

                  1. Introduction. The Company is a party to a Stock Purchase
Agreement (the Stock Purchase Agreement), dated December 11, 1996, with the
Purchaser and pursuant to which the Company has agreed, among other things, to
issue shares of its common stock, par value .001 per share (the Common Stock),
to the Purchaser. This Agreement shall become effective upon the issuance of
such securities to the Purchaser at Closing II pursuant to the Stock Purchase
Agreement. Certain capitalized terms used in this Agreement are defined below;
references to sections shall be to sections of this Agreement. Terms not
otherwise defined herein shall have the meanings assigned to them in the Stock
Purchase Agreement.

                  1.1  Certain Definitions.  As used in this Agreement, the 
following terms shall have the following respective meanings:

                  1.2 "Affiliate"
 means any corporation, company, partnership,
joint venture, or other entity which controls, is controlled by, or is under
common control with Purchaser. For purposes of this definition control shall
mean the direct or indirect ownership of at least fifty (50%) percent or, if
less than fifty (50%) percent, the maximum percentage as allowed by applicable
law of (a) the shares of capital stock entitled to vote for the election of
directors, or (b) ownership interest.

                  "Collaboration Agreement" means that certain Collaboration 
Agreement, dated December 11, 1996 between Regeneron Pharmaceuticals, Inc. and 
Procter & Gamble Pharmaceuticals, Inc..

                  "Commission" means the Securities and Exchange Commission, or
any other Federal agency at the time administering the Securities Act.

                  "Exchange Act" means the Securities Exchange Act of 1934, as

amended, and any successor Federal statute, and the rules and regulations of the
Commission issued under such Act, as they each may, from time to time, be in
effect.

                  "Registration Statement" means a registration statement filed
by the Company with the Commission for a public offering and sale of securities
of the Company (other than a registration statement on Form S-8 or Form S-4, or
their successor forms, or any other form for a limited purpose, or any
registration statement covering only securities proposed to be issued in
exchange for securities or assets of another corporation).


<PAGE>
                  "Registration Expenses means the expenses described in 
subsection 2.3.

                  "Registrable Shares" means (i) the shares of Common Stock
acquired by the Purchaser pursuant to the Stock Purchase Agreement (ii) any
other shares of Common Stock of the Company issued in respect of such shares
(because of stock splits, stock dividends, reclassifications, recapitalization,
or similar event); provided, however, that shares of Common Stock which are
Registrable Shares shall cease to be Registrable Shares upon any sale of such
shares pursuant to a Registration Statement, Section 4(1) of the Securities Act,
or Rule 144 under the Securities Act, or any sale in any manner to a person or
entity which is not entitled to the rights provided by this Agreement.

                  "Securities Act" means the Securities Act of 1933, as amended,
and any successor Federal statute, and the rules and regulations of the
Commission issued under such Act, as they each may, from time to time, be in
effect.

                  1.3  Sale or Transfer of Company's Common Stock; Legend.

                           (a)  The Registrable Shares shall not be sold or 
transferred unless either (i) they first shall have been registered under the 
Securities Act, or (ii) the Company first shall have been furnished with an
opinion of legal counsel, reasonably satisfactory to the Company, to the effect
that such sale or transfer is exempt from the registration requirements of the
Securities Act.

                           (b)  Notwithstanding the foregoing, no registration 
or opinion of counsel shall be required for a transfer made in accordance with 
Rule 144 under the Securities Act.

                           (c)  Each certificate representing the Registrable 
Shares shall bear a legend substantially in the following form:

                The shares represented by this certificate have not been
         registered under the Securities Act of 1933, as amended, and may not be
         offered, sold, or otherwise transferred, pledged, or hypothecated
         unless and until such shares are registered under such Act or an
         opinion of counsel reasonably satisfactory to the Company is obtained
         to the effect that such registration is not required. Additionally, the
         transfer of these shares is subject to the conditions specified in the
         Registration Rights Agreement dated as of December , 1996, between

         Regeneron Pharmaceuticals, Inc. and Procter & Gamble Pharmaceuticals,
         Inc., and no transfer of these shares shall be valid or effective until
         such conditions have been fulfilled. Upon the fulfillment of such
         conditions, Regeneron Pharmaceuticals, Inc., has agreed to deliver to
         the holder hereof a new certificate for the shares 


<PAGE>
         represented hereby registered in the name of the holder hereof. Copies
         of such agreement may be obtained at no cost by written request made by
         the holder of record of this certificate to the secretary of Regeneron
         Pharmaceuticals, Inc.

               The foregoing legend shall be removed from the certificates
representing any Registrable Shares, at the request of the holder thereof, at
such time as such shares become eligible for resale pursuant to Rule 144(k)
under the Securities Act or such shares become publicly tradable pursuant to an
effective Registration Statement.

         2.  Registration under Securities Act, etc.

                  2.1  Incidental Registration.

                           (a)  Whenever the Company proposes to file a 
Registration Statement after the termination or expiration of the Collaboration 
Agreement, at any time and from time to time, it will, prior to such filing, 
give written notice to the Purchaser of its intention to do so and, upon the 
written request of the Purchaser given within ten (10) days after the Company 
provides such notice (which request shall state the intended method of
disposition of such Registrable Shares), the Company shall use its best efforts
to cause all Registrable Shares which the Company has been requested by the
Purchaser to register to be registered under the Securities Act to the extent
necessary to permit their sale or other disposition in accordance with the
intended methods of distribution specified in the request of the Purchaser;
provided that the Company shall have the right to postpone or withdraw any
registration affected pursuant of this subsection 2.1 without obligation to the
Purchaser.

                           (b)  In connection with any offering under this 
subsection 2.1 involving an underwriting, the Company shall not be required to
include any Registrable Shares in such underwriting unless the Purchaser accepts
the terms of the underwriting as agreed upon between the Company and the
underwriters, and then only in such quantity as will not, in the opinion of the
underwriters, jeopardize the success of the offering by the Company. If in the
opinion of the managing underwriters the registration of all, or part of, the
Registrable Shares which the Purchaser has requested to be included would
materially and adversely affect such public offering then the Company shall be
required to include in the underwriting only that number of Registrable Shares,
if any, which the managing underwriter believes may be sold without causing such
adverse effect. Except as set forth in subsection 2.3, the Company will bear all
Registration Expenses in connection with the Purchaser's registration under this
subsection 2.1.


<PAGE>


                           (c)  The Company may refuse to register shares 
eligible for sale under Rule 144(k), unless good cause for inclusion for such
Registrable Shares can be shown; provided good cause will be deemed to be shown
if not all the shares requested by the Purchaser to be registered could
immediately be sold under Rule 144(k) at a price substantially equivalent to the
prevailing market price.

                  2.2 Registration Procedures. If and whenever the Company is
required by the provisions of this Agreement to use its best efforts to effect
the registration of any of the Registrable Shares under the Securities Act, the
Company shall:

                           (a) file with the Commission a Registration 
Statement  with respect to such Registrable Shares and use reasonable efforts to
cause the  Registration Statement to become and remain effective;

                           (b) prepare and file with the Commission any 
amendments and supplements to the Registration Statement and the prospectus 
included in the Registration Statement as may be necessary to comply with the
provisions of the Securities Act and keep the Registration Statement effective
for a period of not less than one hundred twenty (120) days from the effective
date;

                           (c) furnish to the Purchaser such reasonable numbers 
of copies of the prospectus, including a preliminary prospectus, in conformity
with the requirements of the Securities Act, and such other documents as the
Purchaser may reasonably request in order to facilitate the public sale or other
disposition of the Registrable Shares owned by the Purchaser.

                         If the Company has delivered preliminary or final 
prospectuses to the Purchaser and after having done so the prospectus is 
amended  to comply with the requirements of the Securities Act, the Company
shall promptly notify the Purchaser and, if requested, the Purchaser shall
immediately cease making offers of Registrable Shares and return all
prospectuses to the Company. The Company shall promptly provide the Purchaser
with revised prospectuses and, following receipt of the revised prospectuses,
the Purchaser shall be free to resume making offers of the Registrable Shares;

                           (d) use its best efforts to register or qualify the 
Registrable Shares covered by the Registration Statement under securities or
Blue Sky laws of such states as the Purchaser shall reasonably request, and do
any and all other acts and things that may be necessary or desirable to enable
the Purchaser to consummate the public sale or other disposition in such states
of the Registrable Shares owned by the Purchaser; provided, however, that the
Company shall not be required in connection with this paragraph (d) to qualify
as a foreign corporation or execute a general consent to service of process in
any jurisdiction, nor 


<PAGE>
shall it be required to comply with any Blue Sky or other laws, rules or
regulations of any jurisdiction for which compliance or other requirements are,
in the reasonable judgment of the Company, unduly burdensome or would require
any material adjustments in any terms of the offering or in the offering
documents; and


                           (e) In the event of an underwritten public offering, 
enter into and perform its obligations under an underwriting agreement, in usual
and customary form, with the managing underwriter of such offering. The
Purchaser shall also enter into and perform its obligations under such
agreement.

                  2.3 Allocation of Expenses. The Company will indemnify and
hold the Purchaser harmless for the payment of all Registration Expenses of all
registrations under this Agreement, except as set forth in this Agreement. The
term Registration Expenses shall mean all expenses incurred by the Company in
complying with this Section 2, including, without limitation, all registration
and filing fees, exchange listing fees, printing expenses, fee; and
disbursements of counsel for the Company and the Purchaser, state Blue Sky fees
and expenses (except that: the Purchaser shall not cause or request the filing
for Blue Sky approval in any state reasonably refused by the Company), and the
expenses of any special audits incident to or required by any such registration,
but excluding underwriting discounts and selling commissions.

                  2.4 Indemnification. In the event of any registration of any
of the Registrable Shares under the Securities Act pursuant to this Agreement,
the Company will indemnify and hold harmless the Purchaser, and each of its
officers and directors, and each other person, if any, who controls the
Purchaser, within the meaning of the Securities Act or the Exchange Act against
any losses, claims, damages or liabilities, joint or several, to which the
Purchaser or controlling person may become subject under the Securities Act, the
Exchange Act, state securities or Blue Sky laws or otherwise, insofar as such
losses, claims, damages, or liabilities (or actions in respect thereof) arise
out of or are based upon any untrue statement or alleged untrue statement of any
material fact contained in any Registration Statement under which such
Registrable Shares were registered under the Securities Act, any preliminary
prospectus or final prospectus contained in the Registration Statement, or any
amendment or supplement to such Registration Statement, or arise out of or are
based upon the omission or alleged omission to state a material fact required to
be stated therein or necessary to make the statements therein not misleading or
arise out of or are based upon any violation by the Company of the Securities
Act in connection with such registration; and the Company will reimburse the
Purchaser, officer, director, and each such controlling person for any legal or
any other expenses reasonably incurred by the Purchaser, officer, director, or
controlling person in connection with the investigating or defending of any such
loss, claim, damage, 


<PAGE>

liability or action; provided, however, that the Company will not be liable in
any such case to the extent that any such loss, claim, damage or liability
arises out of or is based upon any untrue statement or omission made in such
Registration Statement, preliminary prospectus or prospectus, or any such
amendment or supplement, in reliance upon and in conformity with information
furnished to the Company, in writing, by or on behalf of the Purchaser, officer,
director, underwriter, or controlling person specifically for use in the
preparation thereof.

                  In the event of any registration of any of the Registrable

Shares under the Securities Act pursuant to this Agreement, the Purchaser will
indemnify and hold harmless the Company, each of its directors and officers and
each underwriter (if any) and each person, if any, who controls the Company or
any such underwriter within the meaning of the Securities Act or the Exchange
Act, against any losses, claims, damages, or liabilities, joint or several, to
which the Company, such directors and officers, underwriter or controlling
person may become subject under the Securities Act, Exchange Act, state
securities or Blue Sky laws or otherwise, insofar as such losses, claims,
damages, or liabilities (or actions in respect thereof) arise out of or are
based upon any untrue statement or alleged untrue statement of a material fact
contained in any Registration Statement under which such Registrable Shares were
registered under the Securities Act, any preliminary prospectus or final
prospectus contained in the Registration Statement, or arise out of or are based
upon any omission or alleged omission to state a material fact required to be
stated therein or necessary to make the statements therein not misleading, if
the statement or omission was made in reliance upon and in conformity with
information furnished in writing to the Company, by or on behalf of the
Purchaser, specifically for use in connection with the preparation of such
Registration Statement, prospectus, amendment, or supplement; provided, however,
that the obligations of the Purchaser hereunder shall be limited to an amount
equal to the proceeds of the Registrable Shares sold as contemplated herein;
provided, further, that, with respect to any untrue statement or omission or
alleged untrue statement or omission made in any preliminary prospectus, the
indemnity agreement contained in this subsection 2.4 shall not apply to the
extent that any loss, claim, damage or liability results from the fact that a
current copy of the prospectus was not sent or given to the person asserting any
such loss, claim, damage, or liability at or prior to the written confirmation
of the sale of the Registrable Shares confirmed to such person if it is
determined that it was the responsibility of the Company, any of its directors,
officers or agents to provide such person with a current copy of the prospectus
and such current copy of the prospectus would have cured the defect giving rise
to such loss, claim, damage or liability.

                  Each party entitled to indemnification under this subsection
2.4 (the "Indemnified  Party") shall give notice to the party required to
provide indemnification (the "Indemnifying 


<PAGE>

Party") promptly after such Indemnified Party has actual knowledge of any claim
as to which indemnity may be sought, and shall permit the Indemnifying Party to
assume the defense of any such claim or any litigation resulting therefrom;
provided, that counsel for the Indemnifying Party, who shall conduct the defense
of such claim or litigation, shall be approved by the Indemnified Party (whose
approval shall not be unreasonably withheld); and, provided, further that the
failure of any Indemnified Party to give notice as provided herein shall not
relieve the Indemnifying Party of its obligations under this subsection 2.4. The
Indemnified Party may participate in such defense at such party's expense
provided, however, that the Indemnifying Party shall pay such expense if
representation of such Indemnified Party by the counsel retained by the
Indemnifying Party would be inappropriate due to actual or potential differing
interests between the Indemnified Party and any other party represented by such
counsel in such proceeding. No Indemnifying Party, in the defense of any such
claim or litigation, shall except with the consent of each Indemnified Party,

consent to entry of any judgment or enter into any settlement which does not
include as an unconditional term thereof the giving by the claimant or plaintiff
to such Indemnified Party of a release from all liability in respect of such
claim or litigation, and no Indemnified Party shall consent to entry of any
judgment or settle such claim or litigation without the prior written consent of
the Indemnifying Party.

                  If the indemnification provided for in this subsection 2.4 is
held by a court of competent jurisdiction to be unavailable to an Indemnified
Party, then each Indemnifying Party, in lieu of indemnifying such Indemnified
Party thereunder, hereby agrees to contribute to the amount paid or payable by
such Indemnified Party in such proportion as is appropriate to reflect the
relative fault of the Indemnifying Party on the one hand and of the Indemnified
Party on the other. Notwithstanding the foregoing, the amount the Purchaser
shall be obliged to contribute pursuant to this paragraph of subsection 2.4
shall be limited to an amount equal to the public offering sale price of the
shares sold by the Purchaser.

                  2.5 Information by Holder. The Purchaser shall furnish to the
Company such information regarding the Purchaser and the distribution proposed
by the Purchaser as the Company may request in writing and as shall be required
in connection with any registration, qualification or compliance referred to in
this Section 2.

                  2.6 "Stand-off" Agreement. The Purchaser, if requested by the
Company and an underwriter of Common Stock or other securities of the Company,
shall agree not to sell or otherwise transfer or dispose of any Registrable
Shares or other securities of the Company held by the Purchaser for a specified
period of time (not to exceed one hundred and eighty (180) days) following the
effective date of the Registration Statement; provided, that 


<PAGE>
all officers and directors of the Company enter into similar agreements. Such
agreement shall be in writing in a form satisfactory to the Company and such
underwriter. The Company may impose stop transfer instructions with respect to
the Registrable Shares or other securities subject to the foregoing restrictions
until the end of the stand-off period.

                  2.7  Rule 144 Requirements.  The Company agrees to use 
reasonable efforts to:

                           (a) make and keep public information available, as 
those terms are understood and defined in Rule 144 under the Securities Act;

                           (b) file with the Commission in a timely manner all 
reports and other documents required of the Company under the Securities Act 
and the Exchange Act; and

                           (c) furnish to the Purchaser upon request a copy of 
the most recent annual or quarterly report of the Company, and such other
reports and documents of the Company as the Purchaser may reasonably request to
avail itself of any similar rule or regulation of the Commission allowing it to
sell all or any portion of the Registrable Shares without registration.


         3.  Standstill Agreement.

                  3.1 Except as hereinafter set forth in subsection 3.2, the
Purchaser agrees, for itself and its Affiliates, whether now or hereafter
created or acquired, and any of the Purchaser's pension plans or employee
benefit plan programs sponsored by the Purchaser for which the Purchaser
controls its investment decisions, that it will not, until the earlier of (x)
the termination of the Collaboration Agreement or (y) five (5) years from the
date of this Agreement, without the prior written consent of the Company;

                           (i) directly or indirectly acquire or own 
beneficially and/or of record more than twenty (20%) percent of the Then 
Outstanding Capital Stock of the Company (as hereinafter defined). For purposes
of this Section 3, the Then Outstanding Capital Stock of the Company shall be
deemed to be all of the then issued and outstanding shares of the Common Stock
and all shares of Common Stock into which the then outstanding shares of
preferred stock and any other convertible securities or any options or warrants
issued by the Company are convertible or exercisable, as well as all capital
stock issued as a result of any stock split, stock dividend, or
reclassifications of Common Stock distributable, on a pro rata basis, to all
holders of Common Stock or securities convertible into Capital Stock;

                           (ii) directly or indirectly, solicit proxies or 
consents or become a participant in a solicitation (as such terms 


<PAGE>
are defined in  Regulation 14A under the Exchange Act) in opposition to the
recommendation of the majority of the Board of Directors of the Company with
respect to any matter, or seek to advise or influence any person, with respect
to the voting of any securities of the Company or any of its subsidiaries;

                            (iii) propose or induce any other person to 
propose, directly or indirectly, (x) any merger or business combination
involving the Company or any of its subsidiaries, (y) the purchase or sale of
any assets of the Company or any of its subsidiaries or (z) the purchase of any
of the voting securities of the Company, by tender offer or otherwise (except
pursuant to the exercise of rights, warrants, options, or similar securities
distributed by the Company to holders of voting securities generally);

                           (iv) deposit any voting securities in a voting trust 
or subject any voting securities to any arrangement or agreement with respect to
the voting of voting securities; or

                           (v) advise, assist, or encourage any other person in 
connection with any of the foregoing.

                  3.2 The Purchaser will be relieved of the restrictions set
forth in subsection 3.1 of this Agreement only under the following circumstances
and for the specific transactions as set forth herein below:

                           (i) if a third party, not an Affiliate of the 
Purchaser, directly or indirectly makes a bona fide tender offer or other bona
fide offer for more than twenty (20%) percent but not more than fifty (50%)
percent of the Company's Then Outstanding Capital Stock, and said third party

has, in the reasonable opinion of the Purchaser, the financial resources,
ability and intention to carry out such offer, the Purchaser shall not be
prohibited from purchasing or conducting a tender offer for an amount of shares
equal to the amount of shares sought out be acquired by the third party during
the period of its tender offer;

                           (ii) if a third party, not an Affiliate of the 
Purchaser, directly or indirectly makes a bona fide tender offer or other bona
fide offer for more than fifty (50%) percent of the Company's Then Outstanding
Capital Stock and said third party has, in the reasonable opinion of the
Purchaser, the financial resources, ability and intention to carry out such
offer, the Purchaser shall not be prohibited from purchasing or conducting a
tender offer for all or less than all of the Then Outstanding Capital Stock it
does not already own during the period of the third party's tender offer; or

                           (iii) in the event the Company hereafter issues to a 
third party more than seven (7%) percent of its Then Outstanding Capital Stock 
pursuant to a negotiated written transaction without requiring such third party
to enter into a standstill agreement 


<PAGE>
with provisions substantially as restrictive as those set forth in this Section
3, then Purchaser shall be relieved from its obligations hereunder.

                  3.3 At the time that the Board of Directors of the Company
makes a decision to put the Company up for sale and to entertain bids in
connection with such sale, the Company shall promptly notify the Purchaser of
such decision and in the event that the Company is entertaining a merger
proposal or acquisition proposal which would result in the Company being merged
with and into or acquired by another corporation and such negotiations have
reached a state of finality that the Company believes a public announcement is
warranted, the Company shall forthwith notify the Purchaser of the material
terms of such proposed merger or acquisition which have been agreed upon.
Purchaser's rights under this subsection shall be limited solely to
notification. The Company's obligations under this Section 3 including without
limitation this subsection 3.3 shall terminate upon the termination of the
Collaboration Agreement.

                  3.4 The parties hereto acknowledge and agree that the Company
would be irreparably damaged in the event that any of the provisions of this
Section 3 are not performed in accordance with their specific terms or are
otherwise breached and that monetary damages are not an adequate remedy for said
breach. It is, accordingly, agreed that the Company shall be entitled to
injunctive relief to prevent breaches of this Section 3 by Purchaser and/or its
Affiliates, and to specifically enforce this Section 3 and the terms and
provisions thereof, in addition to any other remedy to which such aggrieved
party may be entitled, at law or in equity. The Company may enter a stop
transfer order with respect to the transfer of voting securities except in
compliance with the termination of this Agreement.

                  3.5 The Company shall give Purchaser prompt notice of the
receipt by the Company of any Schedule 13-D filing from any person or Group
(within the meaning of the Exchange Act) couched in such terms as to put the
Company reasonably on notice of the likelihood that such person or Group has

acquired or is proposing to acquire any shares of Common Stock which results in,
or, if successful, would result in, such person or Group owning or having the
right to acquire more than twenty percent (20%) of the Company's Then
Outstanding Capital Stock.

                  3.6 If Purchaser desires at some date to account for its
investment in the Company pursuant to the equity method, the Company shall
promptly furnish the Purchaser, at Purchaser's sole expense, which estimated
expense shall be prepaid by Purchaser if so requested by the Company, all
information that is required by generally accepted accounting principles to
enable Purchaser to so account. To the extent reasonably available to the
Company and to the extent reasonably requested by Purchaser, the Company shall
provide information (and shall cause its employees, independent public
accountants, and other representatives to do the same), to 


<PAGE>
the extent reasonably available regarding the Company's to, and otherwise
cooperate with, Purchaser so as to enable Purchaser to prepare financial
statements in accordance with accounting principles generally accepted in the
United States and to comply with its reporting requirements and other disclosure
obligations under applicable United States securities laws and regulations (the
"Regulations"). Purchaser agrees to hold all such information in at least the
same degree of confidence as it would hold similar information regarding its
operations and condition, and to disclose it only to the extent required by the
Regulations, provided that there shall be no restriction on Purchaser's right to
disclose its own financial statements, whether or not reflecting or including
such information.

                  3.7 All purchases of securities of the Company by Purchaser
shall be made in compliance with applicable laws and regulations.

         4.  Amendments and Waivers.  This Agreement may be amended, modified, 
supplemented or waived only with the written consent of the parties hereto.

         5. Notices. Except as otherwise provided in this Agreement, all
notices, requests and other communications to any Person provided for hereunder
shall be in writing and shall be given to (a) in the case of the Company, at 777
Old Saw Mill River Road, Tarrytown, New York 10591, attention: President, with a
copy to the attention of General Counsel and Corporate Secretary or (b) in the
case of the Purchaser, at One Procter & Gamble Plaza, Cincinnati, Ohio 45202,
attention: President, with a copy to the attention of General Counsel. Each such
notice, request or other communication shall be effective (i) if given by mail,
72 hours after such communication is deposited in the mails with first class
postage prepaid, addressed as aforesaid or (ii) if given by any other means
(including, without limitation, by air courier), when delivered at the address
specified above.

         6. Successors and Assigns. The provisions of this Agreement, including
the rights and obligations hereunder, shall be binding upon, and inure to the
benefit of, the respective successors and assigns of the Purchaser (the
Transferees) and of the Company, provided that such Transferees shall be an
Affiliate of the Purchaser, and such Transferees shall become the Purchaser for
the all purposes of this Agreement.


         7.  Transfer of Certain Rights.

                           (a) The rights and obligations of the Purchaser 
under  this Agreement may be transferred by the Purchaser to any Affiliate of
the Purchaser. The Company shall be given written notice by the Purchaser at the
time of such transfer stating the name and address of the Transferee and
identifying the securities with respect to which such rights are assigned.


<PAGE>

                           (b) Any Transferee to whom rights are transferred 
shall, as a condition to such transfer, deliver to the Company a written
instrument pursuant to which the Transferee agrees to be bound by the
obligations imposed upon the Purchaser hereunder to the same extent as if such
Transferee were the Purchaser hereunder.

         8.  Descriptive Headings.  The descriptive headings of the several 
sections and paragraphs of this Agreement are inserted for reference only and
shall not limit or otherwise affect the meaning hereof.

         9.  Governing Law.  THIS AGREEMENT SHALL BE CONSTRUED AND ENFORCED IN 
ACCORDANCE WITH, AND THE RIGHTS OF THE PARTIES SHALL BE GOVERNED BY, THE LAWS OF
THE STATE OF NEW YORK WITHOUT REFERENCE TO THE PRINCIPLES OF

CONFLICTS OF LAWS.

         10. Counterparts.  This Agreement may be executed simultaneously in 
any  number of counterparts, each of which shall be deemed an original, but all
such  counterparts shall together constitute one and the same instrument.

         11. Entire Agreement.  This Agreement embodies the entire agreement 
and  understanding between the Company and the Purchaser relating to the subject
matter hereof and supersedes all prior agreements and understandings relating to
such subject matter.

         12. Severability. If any provision of this Agreement, or the
application of such provisions to any Person or circumstance, shall be held
invalid, the remainder of this Agreement, or the application of such provision
to Persons or circumstances other than those to which it is held invalid, shall
not be affected thereby.

                  IN WITNESS WHEREOF, the parties have caused this Agreement to
be executed and delivered by their respective officers thereunto duly authorized
as of the date first above written.

                           REGENERON PHARMACEUTICALS, INC.

                           By __________________________________

                           PROCTER & GAMBLE PHARMACEUTICALS, INC.

                           By __________________________________




                                                                   EXHIBIT 10.31

                             COLLABORATION AGREEMENT

                                     between

                     PROCTER & GAMBLE PHARMACEUTICALS, INC.

                                       and

                         REGENERON PHARMACEUTICALS, INC.

                                December 11, 1996

Execution Copy



<PAGE>



                                       


                             COLLABORATION AGREEMENT

I.         Definitions......................................................3
II.        Scope; Joint Management Committee................................9
III.       Research and Development........................................11
IV.        Commercialization of Products...................................17
V.         License Grants..................................................19
VI.        Royalties and Accounting........................................21
VII.       Patents and Infringement........................................24
VIII.      Confidentiality.................................................27
IX.        Representations, Warranties and Indemnification.................28
X.         Term, Termination...............................................30
XI.        Miscellaneous...................................................35
XII.       Execution.......................................................39



<PAGE>

                             COLLABORATION AGREEMENT

Made as of this 11th day of December, 1996, by and among

         Procter & Gamble Pharmaceuticals, Inc., an Ohio corporation having its
principal offices at One Procter & Gamble Plaza, Cincinnati, Ohio 45202
(hereinafter "Procter & Gamble"), and

         Regeneron Pharmaceuticals, Inc., a New York corporation having its
principal office at 777 Old Saw Mill River Road, Tarrytown, New York 10591-6707
(hereinafter "Regeneron").


         Whereas Regeneron and Procter & Gamble have conducted basic research in
the area of skeletal muscle; and

        Whereas Procter & Gamble and Regeneron share a common vision and commit
to a true collaboration focused on discovering, developing, and commercializing

therapeutic agents in the Field in the Territory (both terms as defined herein);
and

         Whereas Procter & Gamble and Regeneron intend fully to utilize their
capabilities, capitalize on each other's expertise, and put forth Commercially
Reasonable Efforts to achieve this objective, and recognize that each party is
contributing valuable technologies and capabilities to this effort and that the
combination of these compatible and complementary technologies and capabilities
creates the basis for a successful collaboration; and

         Whereas the Parties have also entered into a Stock Purchase Agreement
and Stock Registration Agreement as of the date first written above as part of
this collaboration; so that

The Parties agree as follows:



<PAGE>


                             Article I - Definitions

         1.1. "Affiliate" means any entity that directly or indirectly Owns, is
Owned by, or is under common Ownership with a Party to this Agreement. In no
event will Amgen-Regeneron Partners, any legal entity that Regeneron forms with
Glaxo that relates to their July 1993 agreement, any legal entity that Regeneron
forms with Pharmacopeia, Inc. that relates to their October 1996 agreement, or
any legal entity that Regeneron forms with Procter & Gamble that relates to this
Agreement be deemed to be an Affiliate of Regeneron under this Agreement. "Owns"
or "Ownership" means direct or indirect possession of more than fifty percent
(50%) of the votes of holders of a corporation's voting securities or a
comparable equity interest in any other type of entity.

         1.2.     "Agreement" means the present agreement together with all 
appendices.

         1.3. "Allowable Expense" means Direct Costs to be reimbursed with
respect to a Compound that the JMC approves and authorizes (including without
limitation the nature, amount and calculation of such costs) prior to the time
when such expenses are incurred and shall consist of internal and/or Third Party
(as defined herein) costs incurred by each Party for the research, development,
commercialization, and marketing of Compounds. "Direct Costs" shall mean those
costs that are traceable to the approved activity based upon effort expended
and/or resources consumed to perform such activity; Direct Costs shall not
include without limitation any mark-up or profit above actual costs. Allowable
Expenses will be recognized in accordance with GAAP.

         1.4.     "Anniversary" means the month and day of the Effective Date 

during any year subsequent to the Effective Date.

         1.5.     "Article" means any article of this Agreement.

         1.6.     "Calendar Quarter" means each period of three (3) months 
ending on 31 March or 30 June or 30 September or 31 December.

         1.7. "Commercially Reasonable Efforts" means efforts and resources
commonly used in the research-based pharmaceutical industry for a product at a
similar stage of research, development or commercialization of similar market
potential, taking into account the establishment of the compound or product in
the marketplace, the cost-effectiveness of the efforts or resources while
optimizing profitability, the competitiveness of alternative products in 


<PAGE>

the marketplace, the proprietary position of the product, the likelihood of
regulatory approval given the regulatory structure involved, the profitability
of the product and alternative products and other relevant factors. Commercially
Reasonable Efforts shall be determined on a market by market basis for a
particular Compound, and it is anticipated that the level of effort will change
over time reflecting changes in the status of the Compound and the market
involved.

         1.8. "Competing Product" means any compound, product, method or system
which is or may be used for a purpose or purposes that are the same or
substantially similar to those for which a Compound is or may be used in the
Territory. Competing Product shall not include the compounds ***.

           1.9. "Compound" means a chemical entity, which is not Third Party
Technology, with research or commercial utility in the Field and which primary
site of action is skeletal muscle. Compound includes Research Compounds,
Development Compounds and Marketed Compounds that may be useful in methods of
research, diagnosis, treatment or prevention in the Field. Each Compound shall
also be deemed to include all indications (both inside and outside the Field),
formulations, line extensions, or modes of administration thereof. Compound
shall not include the compounds ***.

         1.10.    "Development Compound" means a Compound that the JMC has 
determined has met Success Criteria and should undergo further development 
pursuant to Section 3.3.

         1.11.    "Effective Date" means the date first written above.

         1.12.    "Exclusivity Term" means the period of time beginning on the 
Effective Date of this Agreement to the end of the Tail Period.

         1.13. "Field" means the diagnosis, prevention and/or treatment of
conditions in humans and animals associated with the promotion or protection of
skeletal muscle mass or function (including, without limitation, the diagnosis,
treatment or prevention of muscle atrophy).

         1.14. "Fiscal Year" means the twelve (12) month period of time from
July 1 to June 30, except that the first Fiscal Year commences on the Effective

Date and ends on June 30, 1997.

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>

         1.15.    "FTE" or "Full Time Equivalent" means one Effort Year of an 
employee or class of employees. "Effort Year" means nineteen hundred and fifty 
(1,950) hours of direct effort expended on approved activities during a Fiscal 
Year.

         1.16.    "GAAP" means generally accepted accounting principles.

         1.17.    "Joint Discovery Research Term" means the period beginning on 
and including the Effective Date and ending upon termination pursuant to 
Section 3.2(c).

         1.18.    "Joint Management Committee" or "JMC" means the committee 
described in Article II.

         1.19. "Joint Non-discovery Research Term" means the period of time
after the termination of the Joint Discovery Research Term when the Parties are
performing research on Research Compounds pursuant to Section 3.2(d).

         1.20. "J-V" means such collaborative relationship as may be established
pursuant to Section 3.8 of this Agreement. J-V may or may not be structured as a
separate legal entity, such as a corporation, partnership, LLC, or such other
form as the Parties may agree. In agreeing on the form of the collaborative
relationship, the Parties shall take appropriate account of, among other
factors, ease of administration and tax liabilities.

         1.21. "Know-how" means the entire right, title and interest in trade
secret Technology. "P&G Know-how" shall mean the entire right, title and
interest in Know-how owned solely or jointly with a Third Party by P&G or an
Affiliate of P&G. "Regeneron Know-how" shall mean the entire right, title and
interest in Know-how owned solely or jointly with a Third Party by Regeneron or
an Affiliate of Regeneron.

         1.22.    "Major Country" means the ***.

         1.23     "Marketed Compound" means a Compound which is sold in any 
country in the Territory.


*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>

         1.24. "Net Sales" means total gross realization less: (i) discounts,
including cash discounts and discounts for special purchases, rebates,
retroactive price reductions or allowances granted or incurred from the billed
amount, (ii) any sales or value added taxes or any other taxes measured by the

amount of sales or gross receipts, and (iii) credits or allowances actually
granted upon claims, rejections or returns, including recalls, regardless of the
party requesting such. As used herein, total gross realization means the list
price for a Compound multiplied by volume in units for units sold or otherwise
transferred by either Party or an authorized agent of either Party to a
customer, but excludes sales or transfers between and among the Parties, the
Parties' Affiliates, or an authorized agent or licensee of either Party, unless
such sale or other transfer is to a customer.

         1.25. "Opting Out Party" means the Party that has elected not to
continue research, development and/or commercialization of a Compound either in
the entire Territory or in one or more specific countries therein.

         1.26.    "Party" means Regeneron or Procter & Gamble.

         1.27. "Patent" shall mean the entire right, title and interest in a
Valid Claim to Technology in a patent application, and all continuing and
divisional patent applications, continuations-in-part, reissue applications and
all other related patent applications claiming priority, indirectly and
directly, to such application, and all patents issuing therefrom, worldwide.
"P&G Patent Rights" shall mean the entire right, title and interest in a Patent
owned solely or jointly with a Third Party by P&G or an Affiliate of P&G.
"Regeneron Patent Rights" shall mean the entire right, title and interest in a
Patent owned solely or jointly with a Third Party by Regeneron or an Affiliate
of Regeneron.

         1.28. "Proceeding Party" means that Party that is not an Opting Out
Party with respect to a Compound either in the entire Territory or in one or
more specific countries therein.

         1.29. "Product Plan" means the annual compilation of objectives,
activities, resource allocations, Success Criteria, Allowable Expenses and
budgets regarding the development and commercialization of Development Compounds
and Marketed Compounds agreed to by the Joint Management Committee, as more
thoroughly described in Section 3.3(c).


<PAGE>

         1.30.    "Research Compound" means a Compound that has not yet been 
designated a Development Compound.

         1.31. "Research Plan" means the annual compilation of objectives,
activities, resource allocations, Success Criteria, Allowable Expenses and
budgets regarding the Parties' collaborative research in the Field agreed to by
the JMC during the Joint Discovery Research Term and Joint Non-discovery
Research Term.

         1.32.    "Royalty Term" means the period from the first Net Sales in 
the first country to the final payment of royalties in the last country 
pursuant to Section 6.1.

         1.33.    "Section" means any section of this Agreement.

         1.34. "Success Criteria" means specific criteria set forth in the

Research Plan that define the minimum technical and/or commercial requirements
for a Research Compound to be designated a Development Compound. For Development
Compounds being developed pursuant to a Product Plan, Success Criteria shall
mean the minimum technical and/or commercial requirements for a Development
Compound to become a commercially viable Marketed Compound.

         1.35. "Sumitomo Compound" means any Compound which is claimed by a
Regeneron Patent and for which Sumitomo Chemical Company Limited has exercised
rights pursuant to its Technology Development Agreement with Regeneron executed
in March 1989.

         1.36.    "Tail Period" means the two (2) years immediately after the 
end of the Joint Discovery Research Term.

         1.37. "Technology" means all inventions, trade secrets and other
information, whether or not patentable, which is useful for the research,
development and/or commercialization of Compounds which are (a) conceived or
reduced to practice by a Party or acquired or licensed by a Party from a Third
Party prior to the Effective Date; (b) conceived or reduced to practice by a
Party or acquired or licensed by a Party from a Third Party during the Joint
Discovery Research Term; (c) conceived or reduced to practice by a Party during
the Tail Period; (d) conceived or reduced to practice by a Party as a result of
activities with respect to a Research Compound during the Joint Non-discovery
Research Term; or (e) a result of development or commercialization of a
Development Compound and/or Marketed Compound during the Term. 


<PAGE>


Technology may include, without limitation, research methods and materials
(including without limitation genetic materials, receptors, cell lines and
transgenic animals) useful in performing research, Compounds, formulations,
chemical synthesis and manufacturing processes, methods of diagnosis and methods
of treatment.

         1.38. "Term" means the period of time beginning on the Effective Date
and unless terminated earlier pursuant to Sections 3.2 or 10.2, ending upon the
expiration of the Royalty Term.

         1.39.    "Territory" means the entire world, excluding Japan with 
respect to any Sumitomo Compound and MuSK and Agrin. Japan shall be included in
the Territory except for Sumitomo Compounds and MuSK and Agrin. "MuSK" shall
mean the materials ***.  "Agrin" shall mean the compounds ***.

         1.40.    "Third Party" means any entity other than Regeneron or 
Procter & Gamble or their Affiliates or a J-V established in accordance with
this Agreement.

         1.41. "Third Party Technology" means Technology owned solely by
Regeneron or its Affiliates in which a Third Party has rights pursuant to an
agreement between such Third Party and Regeneron or its Affiliates prior to the
Effective Date, as specifically set forth in Attachment 9.1.

         1.42. "Valid Claim" shall mean any claim in a published and unexpired

application or patent included within a Patent which claim has not been held
unenforceable, unpatentable or invalid by a decision of a court or other
governmental agency of competent jurisdiction, unappealable or unappealed within
the time allowed for appeal, and which has not been finally abandoned or
admitted to be invalid or unenforceable through disclaimer.

         1.43. "Year" means a calendar year beginning January 1 and ending
December 31, except that the first Year shall be deemed to begin on the
Effective Date and end on December 31, 1997.

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.




<PAGE>
                 Article II - Scope; Joint Management Committee

         2.1.     Scope.

                  (a) The Parties shall work together to research, develop and
commercialize Compounds pursuant to this Agreement in the Territory. During the
Term, neither Party may directly or indirectly develop or commercialize a
Competing Product. Additionally, during the Joint Discovery Research Term, the
Parties shall work together on an exclusive basis in the Field, so that neither
Party shall perform research, development and/or commercialization activities
independently or with a Third Party in the Field, except as agreed by the JMC,
or pursuant to the terms of this Agreement. The Parties shall use Commercially
Reasonable Efforts in performing their obligations under this Agreement.

                  (b) Notwithstanding anything to the contrary contained in this
Agreement, the Parties agree that the *** (hereinafter "Procter & Gamble
Exclusion Compounds") or *** ("Regeneron Exclusion Compounds") shall not be
included within the scope of this Agreement. Procter & Gamble's rights to
research, develop or commercialize Procter & Gamble Exclusion Compounds shall
not be subject to the provisions of this Agreement. Regeneron's rights to
research, develop or commercialize Regeneron Exclusion Compounds shall not be
subject to the provisions of this Agreement.

2.2. Membership. The work under this Agreement shall be performed by the Parties
pursuant to the oversight of the JMC. In particular, the JMC shall have
authority to oversee the research, development and commercialization of
Compounds under this Agreement. The JMC will consist of six (6) members with
three (3) designated by each Party. A chairperson of the JMC will be nominated
alternately by Procter & Gamble and Regeneron to twelve (12) month terms. The
Parties will be free to change their respective representatives, on notice to
the other Party. The JMC will exist until the earlier of termination or
expiration of this Agreement or when one Party is an Opting Out Party with
respect to all Compounds in all countries, unless the Parties otherwise agree.
The JMC may delegate its responsibilities to other committees (e.g., Patent
Committee, Research Committee, Clinical Committee). The initial members of the
JMC shall be selected within fifteen (15) days after the Effective Date. The
first JMC meeting shall occur within thirty (30) days of the Effective Date.

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>

         2.3. Meetings. The JMC will meet at least two (2) times per Year and
may meet at additional times as the Parties shall agree. Either Party may call a
special meeting of the JMC, up to two (2) times per year, on fifteen (15) days'
written notice to the other Party. The chairperson shall send to all JMC members
notices of all regular meetings and agendas for such meetings. The Party
convening a special meeting shall send notices and agenda for such meeting.
Meetings will alternate between the offices of the Parties, or may be held via
teleconference, videoconference or such other place or manner as the Parties may
mutually agree. Members of the Committee shall have their right to participate

in and vote at meetings in person, by telephone, by videoconference or by proxy.
The Party hosting any meeting shall appoint a secretary to the meeting who will
record the minutes of the meeting which will be circulated to the members of the
JMC promptly following the meeting for review, comment, and adoption.

        2.4.      Decision-making Criteria.  Subject to Sections 3.2(a) and 
4.1, all decisions of the JMC shall be made by majority vote and in the exercise
of good faith. Such decisions shall adhere to the ethical and legal standards
for the research-based pharmaceutical industry and utilize Commercially
Reasonable Efforts to research, develop, and commercialize Compounds.

         2.5. Dispute Resolution. Subject to Sections 3.2(a) and 4.1, if a
decision cannot be achieved by the JMC, the matter shall be referred to further
review and resolution by the Chairman or CEO of Regeneron and the President of
Procter & Gamble (the "CEOs"). If the CEOs cannot resolve the issue within
thirty (30) days, the CEOs shall mutually agree upon and appoint to the JMC a
"Temporary Member." "Temporary Member" means a person who is knowledgeable in
the research based pharmaceutical industry, possessing senior executive
experience and skills and not associated with either Party, an Affiliate of
either Party, or a competitor of either Party. If the CEOs cannot mutually agree
on the identity of such Temporary Member within fifteen (15) days of such thirty
(30) day period, the Parties shall request an arbitral panel composed in
accordance with Article XI, sitting in Boston, Mass., to, and such panel shall,
appoint to the JMC a Temporary Member. The JMC shall meet and resolve the
dispute within one week of such appointment of the Temporary Member. All
decisions with respect to the issue in dispute shall be made by majority vote of
the JMC. Such Temporary Member shall be appointed to the JMC until such time as
the CEOs mutually agree that the dispute or disputes have been resolved or until
one Party is deemed to be an Opting Out Party with respect to such Compound (and
country, if applicable) at issue, whichever is earlier. Such Temporary Member
shall be instructed to render his or her votes consistent with the stated


<PAGE>
decision-making criteria of the JMC, as set forth in Section 2.4. The Parties
shall share equally in all costs associated with the appointment of the
Temporary Member.

         2.6. Conduct of Work by Others. It is understood that each Party has
entered into this Agreement based on the specific experience and skill of the
other Party. Accordingly, it is anticipated that work under this Agreement will
be conducted primarily by the Parties. However, it may be commercially
reasonable for the Parties to enter into agreements with commercial or
non-commercial Third Parties to acquire Technology or conduct certain aspects of
such work (e.g., because the Third Party's work provides a favorable
cost/benefit vs. utilizing internal resources). Such agreements may include
(without limitation), acquisition of research methods, Compounds or intellectual
property rights (if applicable), consultation, conduct of certain research
tests, chemical synthesis and supply, safety testing, clinical testing and/or
marketing support. All such work by or acquisition from Third Parties shall be
conducted pursuant to the Research and/or Product Plan and shall be an Allowable
Expense and shall be performed pursuant to written agreements embodying
confidentiality, intellectual property rights and other terms consistent with
the terms set forth in this Agreement, such that the commercial or
non-commercial Third Parties are obligated to assign or exclusively license

without royalty obligations for any patents, patent applications or know-how in
the Field to the Parties or such other terms that are agreed by the Parties.
Information obtained by a Party from any Third Party shall be subject to Article
VIII of this Agreement. All Technology obtained from a Third Party pursuant to
this Section 2.6 shall be jointly owned by the Parties and shall be subject to
Articles V and VII.

         2.7. Record-keeping. Subject to Section 3.4(d), the JMC shall appoint
one Party to keep complete and accurate records pertaining to the Parties'
activities hereunder. The other Party shall have the right to review such
records upon reasonable notice to the recordkeeping party and at reasonable
times. Such records shall be audited annually within a reasonable period after
the end of the Fiscal Year by the recordkeeping party's independent certified
public accountant and are subject to audit by the other Party pursuant to
Section 6.5. In addition, the recordkeeping party shall prepare quarterly
unaudited financials which shall be distributed to the Parties within thirty
(30) days of the end of such period.


                     Article III - Research and Development

        3.1. Research Plan. The Parties have agreed to the draft Research Plan.
The JMC is authorized to finalize the draft Research Plan and amend the Research
Plan from time to time. The Research Plan shall include general goals of the JMC
relating to the Parties' research in the Field and the timing, nature and
priority of resources to be applied and will detail research tasks and goals,
Success Criteria, personnel allocation, outside services and costs, Allowable
Expenses, budgets, and such other matters deemed necessary to implement the
Research Plan in the Joint Discovery Research Term and Joint Non-discovery
Research Term. The Research Plan will include an annual budget and will be
updated by the JMC on at least an annual Fiscal Year basis. The timing and
calculations for the Research Plan budget are contained in Attachment 3.1.

         3.2.     Funding of Research Plan.

                  (a) During the Joint Discovery Research Term, Procter & Gamble
shall fund fifteen (15) Regeneron FTEs per Year for Regeneron's work pursuant to
the Research Plan. Regeneron will fund and supply at least *** Regeneron FTEs
per Year for the same period of time that Procter & Gamble funds *** Regeneron
FTEs pursuant to this Section 3.2(a). For purposes of this Section only,
Regeneron's annual cost per FTE shall be *** (adjusted on a Fiscal Year basis,
starting for the quarter beginning July 1997, for inflation in the prior
calendar year based on changes in the Consumer Price Index for All Urban
Consumers as published by the U.S. Bureau of Labor Statistics). This funding
commitment shall commence on the Effective Date and be payable quarterly in
arrears, except for the first Calendar Quarter of the first Year, which shall be
payable in advance on the Effective Date, subject to Procter & Gamble's right to
terminate such payments, as provided in Section 3.2(c). ***.

                  (b) Regeneron shall use funding provided under this Section
3.2 solely for carrying out the Research Plan. Regeneron shall submit invoices
to Procter & Gamble within forty-five (45) days of the end of each Calendar
Quarter detailing the number of FTEs performing research and development
activities pursuant to the Research Plan, as well as a detailed description of
such activities. Invoices submitted to Procter & Gamble pursuant to this Section
are payable net thirty (30) days after receipt and are subject to Procter &
Gamble's audit pursuant to Section 6.5.

         (c)      Procter & Gamble shall provide the funding to Regeneron for 
research pursuant to Section 3.2(a) for at least three (3) Years.  
Thereafter, subject to Regeneron's funding

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>
commitment in Section 3.2(a), Procter & Gamble shall continue to fund
Regeneron's *** FTEs pursuant to Section 3.2(a) until the earlier of (x)
termination by Procter & Gamble of the Joint Discovery Research Term with at
least *** days' notice prior to the beginning of the fourth, fifth or sixth
Years, or (y) upon designation of a Development Compound by the JMC prior to the
beginning of the sixth Year. The Parties shall equally fund Allowable Expenses

under the Research and/or Product Plans upon the earlier of (i) the beginning of
the fourth Year if the JMC has designated a Development Compound in any prior
Year, (ii) the JMC's designation of a Development Compound after the end of the
third Year, or (iii) the beginning of the sixth Year. Procter & Gamble may
terminate the Joint Discovery Research Term at the beginning of the fourth Year
or any Year thereafter with at least *** notice prior to the beginning of such 
Year. Regeneron may terminate the Joint Discovery Research Term with at least 
*** days' notice prior to the beginning of the sixth Year or any Year 
thereafter.

                  (d) If a Research Compound is identified by either or both
Parties (x) during the Joint Discovery Research Term but has not been designated
a Development Compound prior to termination of the Joint Discovery Research
Term, or (y) during the Tail Period, the Parties shall meet within *** days of
the termination of the Joint Discovery Research Term in the case of (x) or
within *** days of such identification in the case of (y) to agree on a Research
Plan or other disposition (e.g., license to a Party or Third Party) of such
Research Compound. All funding for the Research Plan during the Joint
Non-discovery Research Term shall be shared equally by the Parties. The Joint
Non-discovery Research Term shall be terminated by the JMC's designation of such
Research Compound as a Development Compound, or as otherwise agreed by the
Parties.

         3.3.     Selection of Development Compounds.

                  (a) At the time that the Parties have performed sufficient
research and preclinical testing of a Research Compound and such testing shows
that the Research Compound may have utility in the Field and has met the
Research Plan's predetermined Success Criteria for such Research Compound to be
considered a Development Compound, so that the JMC reasonably determines that
the Research Compound should undergo safety assessment and other preclinical
development activities to determine whether to commence clinical studies with
respect thereto (and thereby such Research Compound being designated as a
Development Compound), then further research, development, and commercialization
of the Development Compound will be conducted in accordance with this Agreement.

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>

                  (b) If the JMC agrees that the Research Compound meets the
Success Criteria but one Party elects to opt out of further development, then
the Party desiring not to proceed in developing the Research Compound shall be
deemed an Opting Out Party with respect to that Research Compound. The
Proceeding Party may develop the Research Compound only if such Research
Compound would not be a Competing Product with respect to other existing
Development Compounds and Marketed Compounds.

                  (c) Within *** after the designation of a Development Compound
by the JMC, the Parties shall meet and agree as to how such Development Compound
will be developed and commercialized and incorporate such agreements into the
Product Plan. The Product Plan shall include general goals of the Parties
relating to the development and commercialization of each Development Compound

and the timing, nature, and priority of resources to be applied and will detail
tasks and goals, personnel allocation, outside services and costs, Success
Criteria, Allowable Expenses, budgets, and such other matters deemed necessary
to implement the Product Plan. The Product Plan will include a spending forecast
through the end of clinical trials for the Development Compound and a budget for
the next Fiscal Year that will be updated by the JMC at least annually on a
Fiscal Year basis. Procter & Gamble is responsible for taking the lead in
proposing such budget with significant and timely input from Regeneron. The
timing and calculations for the typical Product Plan budget is contained in
Attachment 3.1 as an example. The JMC will have complete authority to adopt all
Product Plans.

         3.4.     Funding of Development Compounds and Marketed Compounds; 
Opting Out.

                  (a) All Allowable Expenses for a Development Compound incurred
pursuant to the Product Plan by either Party will be shared equally by the
Parties, whether the JMC designated the Development Compound as such prior to or
after the end of Year 3. Nothing herein shall excuse or mitigate Procter &
Gamble's funding obligations under Section 3.2.

         (b) During the development of a Compound, if one Party is unable to
fund its equal share of Allowable Expenses (the "Owing Party") and proceeds in
good faith to pursue financing for its share from a Third Party, such sum shall
be loaned to the Owing Party by the other Party, accruing interest at the rate
specified in Section 6.4, for a period not to exceed*** from the time the
funding for such Allowable Expenses was initially due ("Advances"). If the Owing
Party fails to timely repay the Advances along with any other Allowable Expenses
that may be payable at that time, the Owing Party shall be deemed to be an
Opting Out Party as of the

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C. 


<PAGE>

date such Advances were initially due. Advances for each Party shall be limited
to *** Advances per Compound and no more than *** Advances for all Compounds
during the same *** period. An example relating to Advances is outlined in
Attachment 3.4(b).

                  (c) If, at any time during a Compound's development or
commercialization, one Party, but not both, elects not to participate in the
further development and/or commercialization of such Compound, then such Party
shall be deemed an Opting Out Party with respect to that Compound, either in
total or on a country-by-country basis pursuant to Section 3.6. At that point,
the Proceeding Party may proceed to develop and/or commercialize such Compound
at its own expense. Unless the Parties otherwise agree, in no event, however,
may a Party opt out from or otherwise refuse to pay its share of Allowable
Expenses to which such Party has committed.

                  (d) If both Parties opt out, the Parties shall use
Commercially Reasonable Efforts to license the Compound, and each Party's
respective share of any income derived from such Compound shall be calculated

pursuant to Section 6.1(b).

                  (e) The Parties' equal funding of Allowable Expenses under the
Product Plan shall commence on the day the JMC designates the Development
Compound as such and be payable quarterly in arrears, based on justification of
Allowable Expenses incurred over the quarter. Regeneron and Procter & Gamble
shall submit reports to each other within thirty (30) days of the end of each
Calendar Quarter detailing the number of FTEs performing research and
development activities pursuant to the Product Plan, Third Party costs and other
costs incurred in research, development and commercialization activities, as
well as a detailed description of such activities. Each Party shall review and
approve the other Party's reports within fifteen (15) days thereafter, subject
to the JMC's approval, if necessary. Procter & Gamble will then calculate the
amount that shall be paid by either Party to the other Party to equalize funding
and so advise Regeneron within seven (7) days. The Party to whom funds are owed
will issue an invoice for the corresponding amount, payable within thirty (30)
days. Costs incurred and paid pursuant to this Section are subject to audit
pursuant to Section 6.5.

         3.5. Research, Development and Commercialization Communication. In
addition to Regeneron's reporting obligations under Section 3.2(b), Regeneron
and Procter & Gamble will submit reports to each other not less than two (2)
times per Fiscal Year presenting a meaningful summary of research, development
and commercialization activities performed under this Agreement. Regeneron and
Procter & Gamble will make presentations of such activities to each

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>
other, beyond that made to the JMC, as reasonably requested by each other. All
Technology generated by the Parties shall be disclosed pursuant to Section 7.1.
Subject to Section 5.4, the Parties shall use their best efforts to communicate
information only in the Field. Regeneron and Procter & Gamble will also
communicate informally and through the JMC to inform each other of research and
development done under this Agreement. Regeneron and Procter & Gamble will
provide each other with raw data in original form or a photocopy thereof for any
and all work carried out under this Agreement as reasonably requested by the
other. Any information contained in such reports and as otherwise communicated
by Regeneron or Procter & Gamble is subject to Article VIII. If one Party is
deemed an Opting Out Party, the Proceeding Party shall annually report to the
Opting Out Party research, development and commercialization activities
performed for Compounds in the Territory for the prior Year sufficient to allow
the Opting Out Party to determine whether the Proceeding Party is utilizing
Commercially Reasonable Efforts.

         3.6. Global Development. The Product Plan shall set forth commercially
reasonable development work (including without limitation clinical studies) to
support acceptable regulatory applications for marketing clearance in all Major
Countries. The costs associated with these activities shall be deemed "Global
Expenses". If either Party fails to pay its share of Global Expenses with
respect to a Compound, such Party shall be deemed an Opting Out Party with
respect to such Compound in the entire Territory. Either Party may opt out of
the commercialization of a Compound on a country-by-country basis provided it

funds its share of total Global Expenses, to the extent that funding of any
development and/or commercialization expenses is solely attributable to one
country and is not considered a Global Expense ("Country Expenses"). A Party
electing to opt out of such Country Expenses shall be deemed an Opting Out Party
with respect to such Compound in that particular country only.

         3.7. J-V Formation. Commencing at the end of the first Year, the
Parties shall negotiate in good faith an agreement by the end of the third Year
that contains all of the terms and conditions of this Agreement, along with
other terms and conditions as the Parties may agree to develop and/or
commercialize Compounds ("J-V Agreement"). In the event that the Parties cannot
finalize such J-V Agreement prior to the end of the third Year, Procter & Gamble
may terminate this Agreement pursuant to Section 3.2(c), elect to continue to
perform research, development and commercialization activities pursuant to this
Agreement until its termination, or negotiate such other arrangement as the
Parties may agree.


<PAGE>

         3.8.     Sumitomo Compounds.
                  (a)      ***
                  (b)      ***

                   Article IV - Commercialization of Products

         4.1.     Marketing and Sales Strategy.  ***.

         4.2.     Net Profits.  The Parties, so long as neither Party is an 
Opting Out Party with respect to such Marketed Compound either in the entire
Territory or in one or more specific countries, as appropriate, will share
equally in the Net Profits of each Compound sold. "Net Profits" mean Net Sales
less Allowable Expenses.

         4.3. Exclusive Distributor. The JMC may appoint either Party or a Third
Party to act as its agent in connection with the marketing, sale and
distribution of Marketed Compounds, and the JMC and/or the Parties (as the case
may be) shall grant to such agent(s) appropriate authority to perform its or
their responsibilities hereunder. In connection with such marketing, sales and
distribution, the following principles shall apply:

                  (a)      the business objective will be to maximize overall 
profits; and

                  (b) in the event that a Third Party is appointed as the
Parties' agent with respect to the marketing, sale and distribution of the
Marketed Compound in a country, Regeneron and Procter & Gamble will each receive
equal shares of any revenue received from such Third Party, so long as neither
Party is an Opting Out Party with respect to such Marketed Compound in such
country.

4.4. Regeneron Co-Promotion Activities. Provided that Regeneron is not an Opting
Out Party with respect to the Compound, Regeneron will have an equal right and
opportunity, but not the obligation, to participate in the sales and marketing
efforts in any country in the Territory as to which it has not opted out by

supplying up to fifty percent (50%) of a Marketed Compound's sales and marketing
efforts with notice to Procter & Gamble within *** of the JMC's decision to
prepare a regulatory application for marketing clearance in the first Major
Country with respect to all Major Countries, then on a country-by-country basis
upon regulatory

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C. 


<PAGE>
filings in such countries other than Major Countries. Regeneron's and Procter &
Gamble's sales and marketing personnel costs shall be an Allowable Expense and
shall be calculated for both Parties on the same basis (e.g., the cost per
salesperson or sales call for Regeneron and Procter & Gamble shall be the same
per year). If Regeneron wants to discontinue or decrease its co-promotion
activities, it must give Procter & Gamble *** months' notice prior to such
discontinuation or decrease.

         4.5. Trademarks; Packaging. After a Compound has been designated a
Development Compound, the Parties shall jointly develop a trademark for such
Development Compound. So long as it is not an Opting Out Party with respect to
such Compound in a country, Procter & Gamble shall file, prosecute and maintain
all trademark applications and registrations for such trademarks, and all
expenses in connection with such activities shall be deemed Allowable Expenses.
As long as neither Party is an Opting Out Party with respect to the Marketed
Compound, such Marketed Compound shall be sold under a single trademark which
shall be owned by Procter & Gamble or, if a legal entity is formed pursuant to a
J-V Agreement, the trademark shall be owned by such entity to the extent legally
permissible. If one Party is an Opting Out Party with respect to such Marketed
Compound, any trademarks shall be owned by the Proceeding Party. So long as
neither Party is an Opting Out Party, the label of the Marketed Compound will
contain the name of Regeneron and Procter & Gamble, to the extent legally
permissible.

                           Article V - License Grants

         5.1. Exclusivity. Procter & Gamble and its Affiliates will not make,
have made, use, import, or sell, or license Technology for use in the Field in
the Territory under Patents and Know-how owned by Procter & Gamble and its
Affiliates (including Procter & Gamble Patents, Procter & Gamble Know-how and
Patents and Know-how owned jointly by the Parties pursuant to Section 5.2)
except under, and in accordance with, the terms of this Agreement. Regeneron and
its Affiliates will not make, have made, use, import, or sell, or license
Technology for use in the Field in the Territory under Patents and Know-how
owned by Regeneron and its Affiliates (including Regeneron Patents, Regeneron
Know-how and Patents and Know-how owned jointly by the Parties pursuant to
Section 5.2) except under, and in accordance with, the terms of this Agreement.

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>

         5.2. Rights in Technology Developed During Agreement. Patents and

Know-how resulting from work by the Parties under this Agreement shall be owned:
(x) by Regeneron, for Technology conceived and reduced to practice solely by
employees of Regeneron or its Affiliates; (y) by Procter & Gamble, for
Technology conceived and reduced to practice solely by employees of Procter &
Gamble or its Affiliates; (z) jointly, for Technology conceived and/or reduced
to practice jointly by employees of Procter & Gamble or its Affiliates and
Regeneron or its Affiliates. Inventorship shall be determined according to the
laws of the United States. Filing, prosecution, maintenance and enforcement of
such Patents shall be handled pursuant to Article VIII.

         5.3. Rights in Technology. Procter & Gamble hereby grants Regeneron the
Sole License to make, have made, use, import and sell Technology in the Field
under Procter & Gamble Patents and Procter & Gamble Know-how. Regeneron hereby
grants Procter & Gamble the Sole License to make, have made, use, import, and
sell Technology in the Field under Regeneron Patents and Regeneron Know-how. As
used herein, "Sole License" shall mean a non-exclusive, royalty free license in
the Territory under Know-how or a Patent, without the right to sublicense,
granted by a "Licensor Party" to the other "Licensee Party," wherein the
Licensor Party shall not grant any Third Party a license to Technology in the
Field under said Know-how or Patent.

         5.4. Rights in Non-Field Inventions. Any compound, composition,
material or method (including without limitation genetic materials, receptors,
cell lines, transgenic animals, pharmaceutical actives, chemical processes,
methods of treatment and methods of diagnosis), which is not a Third Party
Technology and which is conceived of and/or reduced to practice by a Party as a
direct result of work under this Agreement during the Exclusivity Period, but
for which there is no utility in the Field known as of the end of the
Exclusivity Period (herein "Non-Field Invention"), shall be owned:

         (x)      by Regeneron, if conceived and reduced to practice solely by 
employees of Regeneron or its Affiliates;

         (y)      by Procter & Gamble, if conceived and reduced to practice 
solely by employees of Procter & Gamble or its Affiliates; and/or

         (z) jointly, if conceived and/or reduced to practice jointly by
employees of Procter & Gamble or its Affiliates and Regeneron or its Affiliates.

         ***

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>
         5.5. Rights upon Termination of Research. Upon expiration of the
Exclusivity Term and except as set forth in Sections 5.6 and 5.7 with respect to
Compounds under development or commercialization by one or both of the Parties
pursuant to this Agreement, the obligations of the Parties under Section 5.1
shall terminate and the Sole Licenses granted by the Parties under Section 5.3
shall terminate. In addition, Procter & Gamble shall grant Regeneron a
non-exclusive, royalty-free license under Procter & Gamble Know-how and Procter
& Gamble Patents, without the right to sublicense, to make, have made, and use
Technology for the purpose of discovering, developing and/or commercializing

Compounds (other than Compounds identified before the end of the Exclusivity
Term) in the Field. Regeneron shall grant Procter & Gamble a non-exclusive,
royalty-free license under Regeneron Know-how and Regeneron Patents, without the
right to sublicense, to make, have made, and use Technology for the purpose of
discovering, developing and/or commercializing Compounds (other than Compounds
identified before the end of the Exclusivity Term) in the Field.

         5.6. Rights in Compounds under Research, Development and
Commercialization. Subject to Section 3.8, a Party shall not grant any license
to a Third Party in the Territory under any Patent or Know-how owned in whole or
in part by that Party to make, have made, use, import or sell any Compound
during the Term with respect to Compounds that are the subject of joint
research, development and/or commercialization by the Parties under this
Agreement or a J-V Agreement. The Parties shall grant licenses under Patents or
Know-how to each other, or to any jointly owned entity as may be established by
the Parties pursuant to a J-V Agreement, as may be necessary to facilitate
research, development and/or marketing of such Compounds.

         5.7. Grant of License by Opting Out Party. In the event a Party becomes
an Opting Out Party with respect to the development and/or commercialization of
a Compound in its entirety or on a country-by-country basis, then that Opting
Out Party shall grant the Proceeding Party an exclusive license, with the right
to sublicense, to make, have made, use, import and sell such Compound under the
Patents , Know-how, trademarks and copyrights regarding that Compound owned by
the Opting Out Party. The license shall be in all countries of the Territory in
which opting out has been deemed to occur, and shall be subject to the royalty
set forth in Paragraph 7.1. The Opting Out Party shall comply with reasonable
requests for cooperation by the Proceeding Party, and the Proceeding Party shall
reimburse the Opting Out Party for reasonable out-of-pocket expenses incurred
with respect to such cooperation.


<PAGE>

                      Article VI - Royalties and Accounting

         6.1.     Royalty Calculation.

                  (a) The Proceeding Party will pay to the Opting Out Party a
royalty on Net Sales of a Marketed Compound on a country-by-country basis, sold
by the Proceeding Party, its Affiliates, licensees and/or sublicensees in the
Territory at the applicable rate listed below multiplied by the Net Sales in
such country:

                          ***                                      ***
                       ---------                                 -------
***                                                                ***
***                                                                ***
***                                                                ***
***                                                                ***

Such royalty will be paid for a period of *** years from the date of first sale
to a customer of such Compound in a particular country, or for so long as the
manufacture, use, importation or sale of the Compound would, but for the
licenses granted herein, infringe a Valid Claim of a Patent in such country,

whichever is longer.

         (b) If both Parties opt out with respect to a Compound in total or on a
country-by-country basis, opting out either simultaneously or sequentially, then
the Parties shall use Commercially Reasonable Efforts and cooperate with each
other to license the Compound to a Third Party. ***. Examples of the respective
percentages are outlined in Attachment 6.1(b). Reasonable out-of-pocket expenses
incurred in obtaining such licensee shall be shared equally by the Parties.
Notwithstanding the above, either Party may receive, without sharing with the
other Party, reimbursement from such licensee for reasonable, (*** to account
for indirect overhead) costs of research, development and/or commercialization
costs (whether internal or Third Party) to be incurred by such Party for work to
be conducted in the future on behalf of the licensee. Any amounts in excess of
such reimbursement shall be shared in the same proportion as calculated above in
this Section 6.1(b) All amounts from licensees received by either Party shall be
fully disclosed to the other Party and subject to audit (including without
limitation the calculation of Fully-Loaded costs) pursuant to Section 6.5.

         (c) If the Proceeding Party elects to distribute or sublicense a
Compound in any country, and a license must be obtained from a Third Party to
manufacture and/or market such

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>

Compound to avoid a non-frivolous claim of patent infringement, the Proceeding
Party shall offset the following portion of the Third Party license fee, royalty
or other similar payments ("Licensee Fees") against the Opting Out Party's
royalty:

                          ***                                          ***
                       ---------                                     -------
                          ***                                          ***
                          ***                                          ***
                          ***                                          ***
                          ***                                          ***

         Any portion of Licensee Fees paid by the Proceeding Party that is to be
offset against the Opting Out Party's royalty but that exceeds the Opting Out
Party's royalty payable, shall be carried forward and accrue interest pursuant
to Section 6.4 and be offset against future royalties as such royalties become
payable.

         6.2.     Royalty Payment.

                  (a) Royalties payable under Section 6.1 will be paid not later
than sixty (60) calendar days following the end of each Calendar Quarter. All
payments shall be accompanied by a report in writing showing the Calendar
Quarter for which such payment applies, the amount billed to Third Parties for
Marketed Compounds sold during such Calendar Quarter, the deductions from the
amount billed to arrive at the Net Sales, the Net Sales for the Calendar
Quarter, and the royalties due on such Net Sales, such report being broken down

by Marketed Compound and country. All royalties will be paid in the currency
where Net Sales take place or, at the option of the payee, in US dollars at a
rate of exchange on the last business day of the Calendar Quarter as quoted in
The Wall Street Journal (or Citibank, N.A. if such rates are not available in
The Wall Street Journal).

                  (b) All royalties due under this Article VI will be deposited
in a bank chosen by the recipient by the date due. Any amounts or royalties
prohibited from export by a particular country will be deposited in a bank
chosen by the recipient in such country. Any deductions for withholding taxes
imposed by the country in which Net Sales take place will be withheld and

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C. 


<PAGE>

paid as required by law. The paying Party will provide promptly upon request any
receipts from the governmental or taxing authority evidencing payment of such
taxes and will assist the receiving Party in claiming relief from double
taxation.

         6.3. Records. Procter & Gamble and Regeneron will maintain, and will
require their Affiliates and sublicensees to maintain, complete and accurate
records of Net Sales of Marketed Compounds sold subject to the royalty
provisions of Section 6.1 and the audit provisions of Section 6.5.

         6.4.     Interest Rate.  Unless otherwise provided in this Agreement, 
any payments past due will bear interest at the prime rate (such quoted in The 
Wall Street Journal on the first day of the month of the accrual) plus two (2) 
percentage points, compounded monthly.

         6.5. Audit. Records shall be open for audit during reasonable business
hours for a period of three (3) years from creation of individual records for
examination not more often than once each year by an independent certified
public accountant ("CPA") selected by the payee and reasonably acceptable to the
payer for the sole purpose of verifying the correctness of payments to be made
under this Agreement. If the CPA finds a discrepancy of greater than ten (10)
percent of such payment, the CPA shall submit a detailed report regarding the
audit and such discrepancy to both Parties within thirty (30) days of commencing
the audit. The Parties shall attempt to resolve such discrepancy to their mutual
satisfaction during the next fifteen (15) days. If the Parties cannot resolve
the discrepancy, their CEOs shall meet within ten (10) days after such fifteen
(15) day time period. If the CEOs cannot resolve the dispute within five (5)
days, either Party may take such dispute to arbitration pursuant to Section
11.4. The calculation of such payment shall be deemed final (and not subject to
audit or dispute resolution) five (5) years after the period in which such
payment was due, unless arbitration pursuant to Section 11.4 is commenced prior
to such time. Out-of-pocket expenses incurred with respect to such CPA shall be
paid by the payee; however, the payer shall reimburse the payee for such CPA
expenses if the discrepancy is greater than ten (10%) percent, as such
discrepancy is determined by the CEOs or arbitrators.

                     Article VII - Patents and Infringement


         7.1.     Disclosure.  Each Party will promptly disclose to the other 
Party all Technology owned in whole or in part by that Party or in which
Technology such Party otherwise has rights.


<PAGE>

         7.2. Patent Applications. Regeneron and Procter & Gamble will discuss
and evaluate Technology disclosed pursuant to Section 7.1, and confer regarding
the advisability of filing patent applications to cover any Technology. The
Party (herein "Responsible Party") for the filing, prosecution and maintenance
of patent applications shall be: (x) Procter & Gamble, if the subject invention
is made solely by employees of Procter & Gamble; (y) Regeneron, if the subject
invention is made solely by employees of Regeneron; or (z) determined by
agreement of the Parties for all other inventions, taking into account the
nature of the invention and the relationship of the invention to inventions
claimed in other patents or applications. Regeneron and Procter & Gamble will
discuss with each other the advisability of filing Patent applications beyond
the priority country.

        7.3. Filing and Prosecution of Patents. The Responsible Party shall
diligently file, prosecute, issue, and maintain patent applications according to
its own internal standards and for effectively covering other inventions made by
its employees or consultants. The Responsible Party will endeavor to ensure that
all patent applications are filed before any public disclosures so as to ensure
validity of patent applications filed outside of the United States. The
Responsible Party will submit a substantially complete draft of each patent
application to the other Party at least thirty (30) days prior to the
contemplated filing date and consider any comments of the other Party, provided
that in those circumstances where the Responsible Party believes time is of the
essence, the Responsible Party will endeavor to provide the other with such
advance notice as it reasonably can under the circumstances. Regeneron and
Procter & Gamble will confer with each other regarding the prosecution of such
Patent Applications and will copy each other with any official action and
submission in such Patent Applications.

         7.4. Alternate Responsibility for Prosecution. Should Regeneron or
Procter & Gamble not wish to file, prosecute, maintain, or issue a Patent
Application or maintain a Patent covering an Invention at all or in a particular
country, any necessary authority will be granted to the other to file,
prosecute, maintain, and issue such a Patent Application or maintain such a
Patent, all at the expense of the other Party.

         7.5.     Infringement.  Procter & Gamble and Regeneron shall promptly 
notify the other in writing of any infringement of a Patent within the Patent 
Rights licensed or to be licensed pursuant to Article V of which they become 
aware.

         7.6. Enforcement of Patents. Regeneron and Procter & Gamble may, but
shall not be required to, prosecute any alleged infringement or threatened
infringement of a Patent within 


<PAGE>
the Patent Rights of which they are aware or which is brought to their

attention. The prosecuting Party shall act in its own name and at its own
expense unless the other Party at its option pays fifty percent (50%) of all
reasonable out-of-pocket costs. Regeneron and Procter & Gamble shall cooperate
fully with each other including, if required to bring such action, the
furnishing of power of attorney. Any recovery obtained shall belong to the
prosecuting Party unless the other Party has paid fifty percent (50%) of said
costs in which case each Party will receive fifty percent (50%) of any recovery.

         7.7. Alternate Responsibility for Enforcement. If Regeneron or Procter
& Gamble has failed to prosecute under Section 7.6 with respect to alleged or
threatened infringement of one of its Patents (i) three (3) months after it has
been notified in writing by the other of such alleged infringement or (ii) one
(1) month before the time limit, if any, set forth in the appropriate laws and
regulations for the filing of such actions, whichever comes first, the other
may, but shall not be required to, prosecute any alleged infringement or
threatened infringement of the Patent. Such prosecuting Party shall act in its
own name and at its own expense. In such event, both Parties shall cooperate
fully with each other at their own expense, including if required in order to
bring such an action, the furnishing of a power of attorney. Any recovery
obtained shall belong to the prosecuting Party.

        7.8. Trademark Infringement and Enforcement. Procter & Gamble and
Regeneron shall promptly notify the other in writing of any infringement of a
trademark under Section 4.5 of which they become aware. The owner of the
trademark application or registration may, but shall not be required to,
prosecute any such alleged infringement  or threatened infringement. The
prosecuting Party shall act in its own name (unless joinder of the other Party
is required by law in which case it shall be joined) and at its own expense
unless the other Party at its option pays fifty percent (50%) of all reasonable
out-of-pocket costs. Regeneron and Procter & Gamble shall cooperate fully with
each other in such action. Any recovery obtained shall belong to the prosecuting
Party unless the other Party has paid fifty percent (50%) of the costs in which
case each party will receive fifty percent (50%) of any recovery.

        7.9. Alternate Responsibility for Trademark Enforcement. If the owner of
the trademark application or registration has failed to prosecute under Section
7.8 with respect to an alleged or threatened infringement of a trademark (i)
three (3) months after it has been notified in writing by the other of such
alleged infringement or (ii) one (1) month before the time limit, if any, set
forth in the appropriate laws and regulations for the filing of such actions,
whichever comes first, the other Party may, but shall not be required to,
prosecute any alleged infringement 


<PAGE>

or threatened infringement of the trademark. Such prosecuting Party shall act in
its own name and at its own expense. In such event, both Parties shall cooperate
fully with each other at their own expense. Any recovery obtained shall belong
to the prosecuting Party.

                         Article VIII - Confidentiality

         8.1.     Confidentiality and Non-Use Obligations.  Each Party shall 
maintain in confidence all information (herein "Information") which is:


         (a)      Technology disclosed to it by the other Party pursuant to 
Section 7.1;
         (b)      Technology developed by the Party during the Exclusivity 
Term; or
         (c)      other information ("Other Information") disclosed by the 
other Party which is considered confidential by the other Party, and so
designated as confidential in writing when first disclosed or within thirty (30)
days after disclosure if the first disclosure is oral.

         The Party shall take all reasonable precautions to:

         (d) prevent disclosure of such Information to Third Parties, except as
set forth in Section 2.6, Section 8.3 and Section 11.10, or as may be necessary
for the filing or prosecution of patent applications pursuant to Article VII;

         (e)      use Know-how pursuant to the rights and obligations of the 
                  Party pursuant to Article V; and
         (f)      use Other Information only for the purposes of this Agreement.

         These restrictions upon disclosure and use of Information shall 
terminate ten (10) years after the date such Information is developed or
disclosed as set forth above, but shall not apply to any specific portion of
Information which:

           (i.)   is Other Information already in the possession of a Party at 
the time of disclosure by the other Party;

           (ii.)  is or later becomes available to the public other than by 
default by the Party;

           (iii.) is received from a Third Party having no obligation of 
confidentiality to the other Party;

           (iv.)  is Other Information developed by the Party entirely without 
reference or use of Information, as established by probative documentary 
evidence; or

           (v.)   is required to be disclosed by law or government regulation.

         8.2.     Prior Confidentiality Agreements.  The "Confidential 
Disclosure Agreement" dated October 8, 1996 between Regeneron Pharmaceuticals,
Inc. and Procter & Gamble has 


<PAGE>
separately been rendered void and all Information to be kept confidential under
such agreement as of the Effective Date will be subject to the terms of Section
8.1 as if disclosed under this Agreement.

         8.3. Research Manuscripts and Abstracts. It is understood the Parties
may wish to publish or otherwise disclose Technology to a Third Party for
publication in a reputable scientific forum (for example, as an abstract, poster
presentation, lecture, article, book, or any other means of dissemination to the
public). Such disclosures may be made to a Third Party regarding (x) preclinical

research; (y) clinical research disclosing only data that have been locked, if
disclosure presents no significant risk to regulatory filings and serves a
compelling business reason for publication; and (z) other work by the Parties,
upon approval by the JMC. No such disclosure shall be made to a Third Party
until a patent application has been filed adequately describing and claiming any
patentable Technology embodied in such disclosure, pursuant to Article VI. A
Party wishing to make any such disclosure shall submit a complete written draft
of the disclosure to the other Party at least thirty (30) days prior to
submission for the disclosure to a Third Party. The Party shall consider any
comments from the other Party. Any disputes regarding the appropriateness and
content of any such disclosure shall be resolved by the JMC.

          Article IX - Representations, Warranties and Indemnification

         9.1.     Patents.

                  (a) Each Party and their respective Affiliates warrant that,
as of the Effective Date, it has no actual knowledge of any information
rendering invalid or unenforceable any Patent licensed to the other Party under
Article V or VII. Each Party will promptly inform the other Party immediately if
it obtains such information after the Effective Date.

                  (b) Each Party and their respective Affiliates warrant that it
is has no actual knowledge of any patents or Know-how owned by a Third Party
that might prevent, inhibit, or limit the Parties from conducting the research,
development and commercialization activities under this Agreement. Each Party
and their respective Affiliates warrant that, except as disclosed in Attachment
9.1, it has not entered into any agreement with a Third Party that might
prevent, inhibit, or limit the Parties from conducting the research, development
and commercialization activities under this Agreement. Regeneron and its
Affiliates warrant that Attachment 9.1 is a complete list of Third Party
Technology existing as of the Effective Date.


<PAGE>

         9.2. No Guarantee. The Parties understand that the research and
development work to be conducted pursuant to this Agreement will involve
untested, experimental, and currently undeveloped technology and that neither
Regeneron nor Procter & Gamble guarantees the safety or usefulness of any
Compound. Except as expressly set forth in this Agreement, the Parties disclaim
all warranties of any nature, express or implied.

         9.3.     Indemnification.

                  (a) Indemnification Regarding Joint Activities, General. Any
and all liability, damage, loss, cost (including without limitation reasonable
attorneys' fees) and expense resulting from any suits, claims, actions, demands,
liabilities, expenses and/or loss ("Losses") relating to the joint development,
manufacture, use, storage, distribution or sale of any Compound ("Joint
Activities") will be shared equally. Each Party shall indemnify and hold
harmless the other Party for such Party's respective share of such liability;
provided, however, that the portion of Losses due to the gross negligence or
willful or intentional misconduct of either or both Party(ies) shall be governed
by Section 9.3(b).


                  (b) Indemnification by the Parties. Each Party shall indemnify
and hold the other Party harmless from and against that portion of any and all
Losses due to the gross negligence or willful or intentional misconduct of such
indemnifying Party, as well as any Losses that were not caused by Joint
Activities.

                  (c) Indemnification by the Proceeding Party. The Proceeding
Party agrees to save, defend and hold the Opting Out Party harmless from and
against any and all Losses to the extent that such factual allegations forming
the primary basis for such Losses occurred after the Party became an Opting Out
Party with respect to that Compound and/or country. Both Parties shall provide
prompt notice to the other of such potential Losses. The Proceeding Party shall
assume control of the defense of the potential Losses (including without
limitation the right to settle the claim). The Opting Out Party shall provide
reasonable cooperation to the Proceeding Party, and the Proceeding Party shall
reimburse the Opting Out Party its reasonable out-of-pocket expenses.

                  (d) Indemnification Procedure. In the event that either Party
receives notice of potential Losses, such Party shall immediately inform the
other Party and the JMC. The JMC shall decide the manner in which to respond to
and handle the claim. If the JMC cannot decide on how to respond to the claim
prior to five (5) days before the answer is due, the Party receiving the notice
shall answer the claim and take reasonably necessary actions to defend itself,
and the other Party may appoint its own counsel at its own expense, until the
JMC agrees on how to handle the claim.


<PAGE>

                          Article X - Term, Termination

         10.1.    Term.  Unless terminated earlier pursuant to Sections 3.2, 
10.2 or by mutual agreement, this Agreement shall expire at the end of the
Royalty Term.

         10.2. Default. Failure by either Party (the "Defaulting Party") to
comply with any of the material obligations contained in this Agreement, the
Stock Purchase Agreement, the Stock Registration Agreement or any J-V Agreement
shall entitle the other Party (the "Nondefaulting Party") to give to the
Defaulting Party notice specifying the nature of the default and requiring it to
cure such default. If the Defaulting Party disagrees with the existence, extent
or nature of the default, the Parties shall use good faith efforts to resolve
the dispute within thirty (30) days. If (i) such default is not cured with such
thirty (30) day period after the receipt of such notice or (ii) the Parties have
not otherwise resolved the dispute during such thirty (30) day period, the
Nondefaulting Party shall be entitled to initiate arbitration under Section 11.4
and at its sole discretion suspend performance under this Agreement.

         10.3.    Change of Control.

                  (a) In the event of a Change in Control, as that term is
defined in Section 10.5(a), of either the Parties or their respective Affiliates
that have responsibilities or obligations under this Agreement (each
collectively or individually then referred to as the "Acquired Company") and the

Acquired Company is not an Opting Out Party with respect to all Compounds in all
countries under this Agreement, then the Party affiliated with the Acquired
Company shall notify the other Party of any such Change in Control as soon as
the Change in Control may publicly be announced. Upon receipt of any such
notification, the other Party or an Affiliate thereof (the "Electing Company")
shall have the unilateral right to give notice to the Acquired Company within
*** days after its next regularly scheduled board meeting, but in no event
longer than *** days, after receipt of the Acquired Company's notification that
the Electing Company:

                           (i)      elects not to continue the research, 
development and commercialization collaboration, whether or not a J-V has been
formed (the "Option"), in which case a determination of the License Fee pursuant
to Section 10.6 will be made, and within ***

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>

 following such License Fee determination will make the further election either
to purchase the entire interest of the Party affiliated with the Acquired
Company under this Agreement or any J-V Agreement ("Acquired Company Interest")
or offer the Acquired Company the option to purchase the entire interest of the
Electing Company under this Agreement or any J-V Agreement ("Electing Company
Interest") at the License Fee (but in the event that the Acquired Company does
not desire to purchase the Electing Company Interest, the interests of the
Parties shall be disposed of by sale, license, or other commercially reasonable
arrangement for a price that maximizes value for both Parties, paid by a Third
Party or a Party, and each Party shall have the right to receive half of the
consideration thus obtained less any Advances plus accrued interest payable), or

                           (ii)     desires to continue the collaboration for a 
period of up to *** from the date of the Change in Control (the "Trial Period")
upon the express condition that the ultimate parent of the entity acquiring
control of the Acquired Company within *** days thereafter agrees in writing to
such Trial Period and otherwise agrees to be bound by the provisions of this
Agreement, the Stock Registration Agreement, the Stock Purchase Agreement and
any J-V Agreement. If the ultimate parent of the acquiring entity accepts these
conditions, the collaboration shall continue, and the Option shall expire unless
the Electing Company exercises the Option within*** days prior to the expiration
of the Trial Period. If the ultimate parent of the acquiring entity fails to
give notice within the required period that it will be bound by the provisions
of such aforementioned Agreements, the Electing Company shall be deemed to have
exercised the Option as of the expiration of such *** day period and the Parties
shall then follow the procedures set forth in this Section 10.3.

         10.4.    Substantial Stock Accumulation.

                  (a) In the event of a Substantial Stock Accumulation, as that
term is defined in Section 10.5(b), of either the P&G Parent or the Regeneron
Parent (the "Affected Company"), at any time after the Substantial Stock
Accumulation, the Party affiliated with the Affected Company may, but is not
obligated to, inform the other Party in writing that the Party affiliated with

the Affected Company regards such Substantial Stock Accumulation as being not in
the best interests of the collaboration. This notice shall be separate from and
in addition to the notice required under Sections 10.3 and 10.4(b). Upon receipt
of any such notification stating that the Substantial Stock Accumulation is not
in the best interests of the collaboration, the other Party or its Affiliates
(the "Purchasing Company") shall have the option, at its election and upon
notice to

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>
the Affected Company within *** days after receipt of the Affected Company's
notification of a Substantial Stock Accumulation, to purchase the Acquired
Company Interest at the License Fee.

                  (b) In the event of a Substantial Stock Accumulation in either
the P&G Parent or the Regeneron Parent, as soon as the Party affiliated with the
Affected Company has knowledge of the Substantial Stock Accumulation, it shall
give prompt notice to the other Party. Such notice shall be separate from and in
addition to the notice provided for in Sections 10.3 and 10.4(a) and must be
given regardless of whether the Party affiliated with the Affected Company
regards the Substantial Stock Accumulation as being not in the best interest of
the collaboration. From the date on which the Party affiliated with the Affected
Company has notice of the Substantial Stock Accumulation, the following
provisions shall become effective and remain effective until the Substantial
Stock Accumulation is eliminated, unless otherwise agreed:

                           (i)      If the Party that is not affiliated with 
the  Affected Company reasonably determines in good faith that the person or
entity making the Substantial Stock Accumulation is a competitor of such Party
or its Affiliates, such Party may so inform the other Party in writing. Promptly
after receipt of such notice, the Party affiliated with the Affected Company
shall establish a procedure whereby no director or executive employee of the
Affected Company who was not a director or employee of the Affected Company
prior to the Substantial Stock Accumulation, and who was previously a director
or employee of the person or entity making the Substantial Stock Accumulation (a
"Tainted Director or Executive"), shall receive any of the following: (x)
confidential information of the other Party and its Affiliates; and (y)
confidential information of the collaboration, except that any such Tainted
Director or Executive can be given information as to actual and projected sales
and profits of the collaboration.

                           (ii)     If the Party that is not affiliated with 
the Affected Company does not give notice pursuant to this Section 10.4, the
Party affiliated with the Affected Company shall establish a procedure whereby
no Tainted Director or Executive shall receive confidential information of the
other Party and its Affiliates but need not place any restrictions on
confidential or other information of the collaboration.

                           (iii)    In the event of a material violation of 
this Section 10.4, the non-breaching Party may, without resort to the dispute
resolution procedure set forth in Articles II and XI, bring an immediate court
action or enjoin such violation and to recover any damages that it may have

incurred by reasons of such violation.

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>
         10.5.    Definitions.

                  (a) For purposes of this Agreement, a "Change in Control" of a
company shall be deemed to have occurred in the event of (i) a merger,
consolidation, reorganization, recapitalization, the purchase of substantially
all of the company's assets, or other transaction in which or as result of which
the common stock of the company, or a successor entity having the same ownership
as the company, shall cease (except temporarily) to be a publicly traded
security; or (ii) the acquisition by any individual, firm, corporation, or
entity (other than any profit sharing or other employee benefit plan of the
company or any Affiliate, or any employee or group of employees or former
officers an/or directors of the company or its Affiliates) of beneficial
ownership, directly or indirectly, of securities of the company representing
more than *** of the combined voting power of the company's then outstanding
voting securities. Notwithstanding the foregoing, The Procter & Gamble Company
directly or indirectly must have at least *** percent of the combined voting
power of Procter & Gamble's outstanding voting securities, otherwise there shall
be a Change of Control of Procter & Gamble.

                  (b) A "Substantial Stock Accumulation" of a company shall be
deemed to have occurred in the event of the accumulation by any individual,
firm, corporation, or entity (other than any profit sharing or other employee
benefit plan of the company or any Affiliate, or any employee or group of
employees or former officers an/or directors of the company or its Affiliates)
of beneficial ownership, directly or indirectly, of securities of the company
representing more than *** of the combined voting power of the company's then
outstanding voting securities. Notwithstanding the foregoing, Leonard Schleifer,
M.D., Ph.D., the present President and Chief Executive Officer of Regeneron, may
accumulate more than *** percent of Regeneron's or Regeneron's Parent's combined
voting power of its outstanding securities and no Substantial Stock Accumulation
for Regeneron shall be deemed to have occurred. For the purposes of this Section
10.5(b), Dr. Schleifer's ownership of securities of Regeneron or Regeneron's
Parent shall be deemed to be his direct or indirect ownership of capital shares
or options to purchase such capital shares of Regeneron or Regeneron's Parent
and the direct or indirect ownership of such shares by members of his family
living in his household to the extent that Dr. Schleifer retains voting control,
the power to exercise such options, and the right to dispose of such shares, and
shall not include any other shares over which he does not possess Beneficial
Ownership, as defined in the Securities and Exchange Act of 1934, as amended.

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>
         10.6.    The "License Fee" for purposes of Sections 10.3 and 10.4 
shall be determined as follows:

                  (a)      License Fee has two components:  a Valuation (as 

defined herein) of the Parties' interest in the Agreement or J-V Agreement with
respect to Compounds to which neither Party has opted out in total and a running
royalty on Net Sales of any Compound for which neither Party has opted out, such
rate and term being calculated as per Section 6.1 ("Running Royalty"). Each
Party shall designate an investment banking firm of its choice, and each
investment banking firm will be asked to prepare an appraisal as to the fair
market value of the collaboration as a going concern that would be received in
cash from a Third Party if a sale of the collaboration were made to a Third
Party, taking into account any contractual obligation of either Party or its
Affiliates to refrain from manufacturing or marketing a product competitive with
the Products in the Territory for any period, the value of the information,
Patents and Know-how, and other assets being licensed and the potential market
for such Compounds in the Territory ("Fair Market Value"). The Fair Market Value
shall not include Compounds in specific countries or in the entire Territory for
which either Party is an Opting Out Party, as such royalty shall continue to be
governed pursuant to Section 6.1, regardless of a Change of Control. *** The
investment bankers will be asked to submit their Valuations within thirty (30)
days after the Purchase Date. In the event of a Party's failure to obtain an
investment banking firm's Valuation within thirty (30) days after the Purchase
Date, the Valuation will be the Valuation determined by the investment banking
firm appointed by the other Party. An example of the operation of the License
Fee is set forth in Attachment 10.6(a).

                  (b) If the difference between the lower Valuation and the
higher Valuation is not more than *** of the higher Valuation, or if the
Valuations are equal, the final Valuation shall be the average of the
Valuations. If the difference between the *** Valuations is more than *** of the
higher Valuation, the investment bankers will select a third investment banking
firm from those known as major bracket investment banking firms, and that firm
shall also prepare a Valuation. The third investment banking firm will not have
access to the Valuations prepared by the other investment banking firms. The ***
Valuations that are the closest in value then shall be averaged, and the
resulting average shall be the final Valuation.

                  (c) The purchase of the interest shall thereafter be
consummated by payment of the Valuation and the obligation to pay the Running
Royalty within *** days after receipt of all investment bankers' valuations or
such later date upon which all necessary regulatory

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>
approvals have been obtained and/or regulatory waiting periods have expired.
Advances (if applicable) shall be first subtracted from or added to (as the case
may be) the Valuation, then any excess Advance shall be immediately payable by
the Owing Party.

                  (d) Each Party shall bear the expense of obtaining the
Valuation of the investment bankers selected by such Party, and if a third
investment banker is selected, the expense of obtaining its Valuation shall be
borne equally by the Parties.

                  (e) Unless otherwise agreed in writing by the Parties, the

License Fee for a license under Sections 10.3, 10.4 and 10.5 shall be calculated
as of the date of the Electing Company's notice that it elects to exercise the
Option under Sections 10.3 or 10.4 or the Purchasing Company's notice that it
desires to license the interest of the Party affiliated with the Affected
Company under Section 10.3 (such date shall be referred to as the "Purchase
Date").

                  (f) During the pendency of the Option election and valuation
process, the Parties shall continue to perform their customary activities under
this Agreement or any J-V Agreement.

                           Article XI - Miscellaneous

         11.1. Force Majeure. Neither Party shall lose any rights hereunder or
be liable to the other Party for damages or loss on account of failure of
performance by the Defaulting Party if the failure is occasioned by government
action, war, fire, explosion, flood, strike, lockout, embargo, act of God, or
any other similar cause beyond the reasonable control of the Defaulting Party,
provided that the Party claiming force majeure has exerted all reasonable
efforts to avoid or remedy such force majeure and given prompt notice to the
other Party.

         11.2. Notices. Any notices or communications provided for in this
Agreement to be made by either of the Parties to the other shall be in writing,
in English, and shall be made by prepaid air mail with return receipt addressed
to the other at its address set forth above. Any such notice or communication
may also be given by hand or facsimile to the appropriate designation with
confirmation of receipt. Either Party may by like notice specify an address to
which notices and communications shall thereafter be sent. Notices sent by mail
shall be effective upon receipt; notices given by hand shall be effective when
delivered.

<PAGE>

                  Notices for Regeneron shall be sent to:

                           Regeneron Pharmaceuticals, Inc.
                           Attn:  Corporate Secretary
                           777 Old Saw Mill River Road
                           Tarrytown, New York  10591-6707

                  With copy to:

                           Regeneron Pharmaceuticals, Inc.
                           Attn:  General Counsel
                           777 Old Saw Mill River Road
                           Tarrytown, New York  10591-6707

                  Notices for Procter & Gamble shall be sent to:

                           Procter & Gamble Pharmaceuticals, Inc.
                           Attn:  President
                           One Procter & Gamble Plaza
                           Cincinnati, Ohio  45202


                  With copy to:

                           Procter & Gamble Pharmaceuticals, Inc.
                           Attn:  Associate General Counsel
                           Blue Ash Office Center
                           10200 Alliance Road
                           Cincinnati, Ohio  45242-4716

         11.3. Governing Law. This Agreement shall be governed by the laws of
the State of Delaware, as such laws are applied to contracts entered into and to
be performed within such state. Any claim or controversy arising out of or
related to this Agreement or any breach hereof shall be submitted to arbitration
pursuant to Section 11.4. The United Nations Convention on Contracts for the
International Sale of Goods will not apply to this Agreement.

         11.4. Arbitration. Subject to Sections 2.5 and 10.4(b)(iii),
disagreements under this Agreement shall be settled by arbitration in accordance
with the commercial arbitration rules of the American Arbitration Association.
The parties further agree that each such disagreement be 


<PAGE>
submitted to a panel of three (3) impartial arbitrators with each Party
selecting one (1) arbitrator within fifteen (15) days of a request for
arbitration and the two (2) selected arbitrators selecting a third arbitrator
who is experienced in the United States pharmaceutical industry within thirty
(30) days after the request. Any arbitration hereunder shall commence within
thirty (30) days after appointment of the third arbitrator and shall be held in
Boston, Mass., U.S.A. Upon reasonable notice and prior to any hearing, the
Parties will allow document discovery and will disclose all materials relevant
to the subject matter of the dispute. The arbitrators shall make final
determinations as to any discovery disputes. The decision of the arbitrators
shall be rendered no later than sixty (60) days after commencement of
arbitration. The costs of arbitration shall be split by the parties unless the
arbitrators decide otherwise. Any judgment or decision rendered by the panel
shall be binding upon the Parties and shall be enforceable by any court of
competent jurisdiction.

         11.5. Non-waiver of Rights. Except as specifically provided for herein,
the waiver from time to time by any of the parties of any of their rights or
their failure to exercise any remedy shall not operate or be construed as a
continuing waiver of same or of any other of such Party's rights or remedies
provided in this Agreement.

         11.6. Severability. If any term, covenant, or condition of this
Agreement or the application thereof to any Party or circumstance shall, to any
extent, be held to be invalid or unenforceable, then (i) the remainder of this
Agreement, or the application of such term, covenant or condition to Parties or
circumstances other than those as to which it is held invalid or unenforceable,
shall not be affected thereby and each term, covenant, or condition of this
Agreement shall be valid and be enforced to the fullest extent permitted by law
and (ii) the Parties hereto covenant and agree to renegotiate any such term,
covenant, or application thereof in good faith in order to provide a reasonably
acceptable alternative to the term, covenant, or condition of this Agreement or
the application thereof that is invalid or unenforceable, and in the event that

the Parties are unable to agree upon a reasonably acceptable alternative, then
the Parties agree that a submission to arbitration shall be made in accordance
with Section 11.4 to establish an alternative to such invalid or unenforceable
term, covenant, or condition of this Agreement or the application thereof, it
being the intent that the basic purposes of this Agreement are to be
effectuated.

         11.7. Entire Agreement. This Agreement sets forth all the covenants,
promises, agreements, warranties, representations, conditions, and
understandings between the Parties hereto in the Field, with the exception of
any agreements by the Parties executed at an even date 


<PAGE>
hereof, and supersedes and terminates all prior agreements and understanding
between the parties in the Field. No subsequent alteration, amendment, change,
or addition to this Agreement shall be binding upon the Parties hereto unless
reduced to writing and signed by the respective authorized officers of the
Parties.

         11.8.    Survival.  Sections 5.4, 5.5 and 8.1 shall survive the 
termination of this Agreement for to the extent specified therein. Section 9.3
and any accrued obligations under this Agreement shall survive termination of
this Agreement without limit as to time.

         11.9.    Assignment.

                  (a) Procter & Gamble and Regeneron may assign any of their
rights or obligations under this Agreement in any country of the Territory to
any Affiliates; provided, however, that such assignment shall not relieve the
assigning Party of its responsibility for performance of its obligations under
this Agreement.

                  (b) The Parties recognize that each may perform some of its
obligations hereunder through Affiliates; provided, however, that Procter &
Gamble and Regeneron shall remain responsible and be guarantors of such
performance by their Affiliates and shall cause their Affiliates to comply with
the provisions of this Agreement in connection with such performance.

                  (c) Procter & Gamble and Regeneron may only assign their
rights under this Agreement in any country of the Territory to a Third Party
with written permission of the other Party, which permission will only be given
at its sole discretion.

         11.10.   Publicity.

                  (a) Procter & Gamble and Regeneron will jointly discuss and
promptly agree, based on the principles of Section 11.10(b), on any press
releases and any other public statements regarding the execution and the subject
matter of this Agreement, the research to be conducted under this Agreement or
any other aspect of this Agreement, subject in each case to disclosure otherwise
required by law or regulation.

                  (b) In the discussion and agreement of Section 11.10(a), the
principles observed by Procter & Gamble and Regeneron will be accuracy, the

requirements for confidentiality under Article IX, the advantage a competitor of
Procter & Gamble or Regeneron may gain from any statement under Section
11.10(a), the requirements of disclosure under any securities laws or
regulations of the United States, including those associated with SEC and
regulatory filings and public offerings, the restrictions imposed by the Federal
Food, Drug and 


<PAGE>
Cosmetic Act, and the standards and customs in the pharmaceutical
industry for such disclosures by companies comparable to Procter & Gamble and
Regeneron.

         11.11.   Counterparts.  This Agreement may be executed in one or more 
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one in the same instrument.

         11.12.   No Solicitation.  During the Term of this Agreement, the 
Parties shall not directly or indirectly solicit the other Party's employees for
employment or other consulting arrangements.

                             Article XII - Execution

         12.1. In witness whereof the Parties have executed this Agreement in
duplicate originals by their proper officers as of the date and year first
written above.

Procter & Gamble Pharmaceuticals, Inc.

By:
   ------------------------------
         G. Gilbert Cloyd
         President

Regeneron Pharmaceuticals, Inc.

By:
   ------------------------------------
         Leonard S. Schleifer, M.D., Ph.D.
         President and Chief Executive Officer



<PAGE>


                                 Attachment 3.1

         Timing and Calculation of Research and/or Product Plan Budgets

Budget Process

1)       ***

2)       ***


3)       ***

Attachment 3 cont.

Budget Cost Development

1)       ***

Attachment 3 cont.

2)       ***

               Attachment 3.4(b) -- Example of Advances Operation

                        FUNDING OF DEVELOPMENT CANDIDATES

                                      ***


                                Attachment 6.1(b)

                 Each Party's Share of Royalties or Other Income

                            When Both Parties Opt Out

                                      ***

*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.


<PAGE>
         Attachment 9.1 - Agreements Relating to Third Party Technology

Technology Development Agreement dated as of March 20, 1989, between Sumitomo
         Chemical Company, Limited and Regeneron Pharmaceuticals, Inc.

Collaboration Agreement dated as of August 31, 1990, between Amgen Inc. and 
         Regeneron Pharmaceuticals, Inc.

Collaboration Agreement dated as of July 22, 1993, between Glaxo Group Limited
         and Regeneron Pharmaceuticals, Inc.

Research Development Agreement dated as of June 2, 1994, between Sumitomo
         Pharmaceuticals Company, Ltd., and Regeneron Pharmaceuticals, Inc.

Collaboration Agreement dated as of October 9, 1996, between Pharmacopeia, Inc.,
         and Regeneron Pharmaceuticals, Inc.



<PAGE>


                               Attachment 10.6(a)


                        Example of License Fee Operation

      Scenario                                           License Fee Operation

                                       ***













*** Certain material has been omitted from this section pursuant to a request
for confidential treatment and has been filed separately with the S.E.C.





<PAGE>


                                                                      Exhibit 11
                                                            --------------------


<TABLE>
<CAPTION>

                         REGENERON PHARMACEUTICALS, INC.
                   STATEMENT OF COMPUTATION OF LOSS PER SHARE
              for the years ended December 31, 1996, 1995 and 1994

                                                1996           1995            1994
                                           ----------------------------------------------
<S>                                         <C>             <C>            <C>          
Primary:

Net loss                                    ($32,423,778)   ($23,507,274)  ($30,654,740)
                                           ==============================================

Weighted average number
of Class A and common shares
outstanding during the period                 24,463,516      19,768,466     18,866,993
                                           ==============================================
Net loss per share                                ($1.33)         ($1.19)        ($1.62)
                                           ==============================================




Fully diluted:
Net loss                                    ($32,423,778)   ($23,507,274)  ($30,654,740)
                                           ==============================================

Weighted average number
of Class A and common shares
outstanding during the period                 24,463,516      19,768,466     18,866,993

Shares issuable upon exercise of options       2,963,450       2,413,147        480,781

Shares assumed to be repurchased under
the treasury stock method                     (1,270,915)       (980,997)      (288,146)
                                           ----------------------------------------------

                                              26,156,051      21,200,616     19,059,628
                                           ==============================================

Net loss per share                                ($1.24)         ($1.11)        ($1.61)
                                           ==============================================

</TABLE>







<PAGE> 



                                                                   Exhibit 23.1

                         CONSENT OF INDEPENDENT ACCOUNTANTS

We consent to the incorporation by reference in the registration statements of
Regeneron Pharmaceuticals, Inc. on Form S-8 (File Nos. 33-50480, 33-85330 and
33-97176) of our report, which is based in part on the report of other auditors,
dated February 14, 1997, except for the second paragraph of Note 8(e) for which
the date is March 19, 1997, on our audits of the financial statements of
Regeneron Pharmaceuticals, Inc. as of December 31, 1996 and 1995, and for the
years ended December 31, 1996, 1995 and 1994, which report is included in this
Annual Report on Form 10-K.

                                                     COOPERS & LYBRAND L.L.P.

New York, New York
March 21, 1997








<PAGE>
                                                                    Exhibit 23.2

               CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS

We consent to the incorporation by reference in the Registration Statement (Form
S-8 No. 33-50480) pertaining to the Regeneron Pharmaceuticals, Inc. 1990 Long
Term Incentive Plan and in the Registration Statements (Form S-8 No. 33-85330
and Form S-8 No. 33-97176) pertaining to the Regeneron Pharmaceuticals, Inc.
Amended and Restated 1990 Long Term Incentive Plan of our report dated February
5, 1997, with respect to the financial statements of Amgen-Regeneron Partners
included in Regeneron Pharmaceuticals, Inc.'s Annual Report (Form 10-K) for the
year ended December 31, 1996.

                                                              ERNST & YOUNG LLP

Los Angeles, California
February 5, 1997







<PAGE>

                                                                      Exhibit 24

                                Power of Attorney
                                -----------------

         KNOW ALL PERSONS BY THESE PRESENTS, that I the undersigned, a director
of Regeneron Pharmaceuticals, Inc., a New York corporation, do hereby constitute
and appoint Leonard S. Schleifer and Paul Lubetkin, and each of them severally
to be my true and lawful attorneys-in-fact and agents each acting alone with
full power of substitution and revocation, to sign my name to the Regeneron
Pharmaceuticals, Inc. Annual Report on Form 10-K for the year ended December 31,
1996 and any and all amendments to such Annual Report, and to file the same,
with all exhibits thereto, and other documents in connection therewith, with the
Securities and Exchange Commission, and I hereby grant unto said
attorneys-in-fact and agents full power and authority to do and perform each and
every act and thing requisite and necessary to be done, as full as to all
intents and purposes as such person might or could do in person, hereby
ratifying and confirming all that said attorney-in-fact and agent or his
substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, I have subscribed these presents as of March 14, 1997.
                                                                     ----
                                                              




                                                        /s/ P. Roy Vagelos
                                                        ------------------
                                                        P. Roy Vagelos, M.D.

                                     

<PAGE>

                                Power of Attorney
                                -----------------

         KNOW ALL
 PERSONS BY THESE PRESENTS, that I the undersigned, a director
of Regeneron Pharmaceuticals, Inc., a New York corporation, do hereby constitute
and appoint Leonard S. Schleifer and Paul Lubetkin, and each of them severally
to be my true and lawful attorneys-in-fact and agents each acting alone with
full power of substitution and revocation, to sign my name to the Regeneron
Pharmaceuticals, Inc. Annual Report on Form 10-K for the year ended December 31,
1996 and any and all amendments to such Annual Report, and to file the same,
with all exhibits thereto, and other documents in connection therewith, with the
Securities and Exchange Commission, and I hereby grant unto said
attorneys-in-fact and agents full power and authority to do and perform each and
every act and thing requisite and necessary to be done, as full as to all
intents and purposes as such person might or could do in person, hereby
ratifying and confirming all that said attorney-in-fact and agent or his
substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, I have subscribed these presents as of March 13, 1997.
                                                                     ----



                                             /s/ Charles A. Baker
                                             --------------------
                                             Charles A. Baker



<PAGE>

                                Power of Attorney
                                -----------------

         KNOW ALL PERSONS BY THESE PRESENTS, that I the undersigned, a director
of Regeneron Pharmaceuticals, Inc., a New York corporation, do hereby constitute
and appoint Leonard S. Schleifer and Paul Lubetkin, and each of them severally
to be my true and lawful attorneys-in-fact and agents each acting alone with
full power of substitution and revocation, to sign my name to the Regeneron
Pharmaceuticals, Inc. Annual Report on Form 10-K for the year ended December 31,
1996 and any and all amendments to such Annual Report, and to file the same,
with all exhibits thereto, and other documents in connection therewith, with the
Securities and Exchange Commission, and I hereby grant unto said
attorneys-in-fact and agents full power and authority to do and perform each and
every act and thing requisite and necessary to be done, as full as to all
intents and purposes as such person might or could do in person, hereby
ratifying and confirming all that said attorney-in-fact and agent or his
substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, I have subscribed these presents as of March 14, 1997.
                                                                     ----




                                         /s/ Michael S. Brown
                                         --------------------
                                         Michael S. Brown, M.D.


<PAGE>

                                Power of Attorney
                                -----------------

         KNOW ALL PERSONS BY THESE PRESENTS, that I the undersigned, a director
of Regeneron Pharmaceuticals, Inc., a New York corporation, do hereby constitute
and appoint Leonard S. Schleifer and Paul Lubetkin, and each of them severally
to be my true and lawful attorneys-in-fact and agents each acting alone with
full power of substitution and revocation, to sign my name to the Regeneron
Pharmaceuticals, Inc. Annual Report on Form 10-K for the year ended December 31,
1996 and any and all amendments to such Annual Report, and to file the same,
with all exhibits thereto, and other documents in connection therewith, with the
Securities and Exchange Commission, and I hereby grant unto said
attorneys-in-fact and agents full power and authority to do and perform each and
every act and thing requisite and necessary to be done, as full as to all
intents and purposes as such person might or could do in person, hereby
ratifying and confirming all that said attorney-in-fact and agent or his
substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, I have subscribed these presents as of March 14, 1997.
                                                                     ----




                                            /s/ Alfred G. Gilman
                                            ------------------------------
                                            Alfred G. Gilman, M.D., Ph.D.


<PAGE>

                                Power of Attorney
                                -----------------

         KNOW ALL PERSONS BY THESE PRESENTS, that I the undersigned, a director
of Regeneron Pharmaceuticals, Inc., a New York corporation, do hereby constitute
and appoint Leonard S. Schleifer and Paul Lubetkin, and each of them severally
to be my true and lawful attorneys-in-fact and agents each acting alone with
full power of substitution and revocation, to sign my name to the Regeneron
Pharmaceuticals, Inc. Annual Report on Form 10-K for the year ended December 31,
1996 and any and all amendments to such Annual Report, and to file the same,
with all exhibits thereto, and other documents in connection therewith, with the
Securities and Exchange Commission, and I hereby grant unto said
attorneys-in-fact and agents full power and authority to do and perform each and
every act and thing requisite and necessary to be done, as full as to all
intents and purposes as such person might or could do in person, hereby
ratifying and confirming all that said attorney-in-fact and agent or his
substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, I have subscribed these presents as of March 13, 1997.
                                                                     ----





                                             /s/ Joseph L. Goldstein
                                            ---------------------------
                                             Joseph L. Goldstein, M.D.


<PAGE>

                                Power of Attorney
                                -----------------

         KNOW ALL PERSONS BY THESE PRESENTS, that I the undersigned, a director
of Regeneron Pharmaceuticals, Inc., a New York corporation, do hereby constitute
and appoint Leonard S. Schleifer and Paul Lubetkin, and each of them severally
to be my true and lawful attorneys-in-fact and agents each acting alone with
full power of substitution and revocation, to sign my name to the Regeneron
Pharmaceuticals, Inc. Annual Report on Form 10-K for the year ended December 31,
1996 and any and all amendments to such Annual Report, and to file the same,
with all exhibits thereto, and other documents in connection therewith, with the
Securities and Exchange Commission, and I hereby grant unto said
attorneys-in-fact and agents full power and authority to do and perform each and
every act and thing requisite and necessary to be done, as full as to all
intents and purposes as such person might or could do in person, hereby
ratifying and confirming all that said attorney-in-fact and agent or his
substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, I have subscribed these presents as of March 19, 1997.
                                                                     ----




                                             /s/ Fred A. Middleton
                                             ---------------------
                                             Fred A. Middleton


<PAGE>

                                Power of Attorney
                                -----------------

         KNOW ALL PERSONS BY THESE PRESENTS, that I the undersigned, a director
of Regeneron Pharmaceuticals, Inc., a New York corporation, do hereby constitute
and appoint Leonard S. Schleifer and Paul Lubetkin, and each of them severally
to be my true and lawful attorneys-in-fact and agents each acting alone with
full power of substitution and revocation, to sign my name to the Regeneron
Pharmaceuticals, Inc. Annual Report on Form 10-K for the year ended December 31,
1996 and any and all amendments to such Annual Report, and to file the same,
with all exhibits thereto, and other documents in connection therewith, with the
Securities and Exchange Commission, and I hereby grant unto said
attorneys-in-fact and agents full power and authority to do and perform each and
every act and thing requisite and necessary to be done, as full as to all
intents and purposes as such person might or could do in person, hereby
ratifying and confirming all that said attorney-in-fact and agent or his
substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, I have subscribed these presents as of March 13, 1997.
                                                                     ----




                                                    /s/ Eric M. Shooter
                                                    ----------------------
                                                    Eric M. Shooter, Ph.D.



<TABLE> <S> <C>


<ARTICLE> 5
       
<S>                                        <C>
<PERIOD-TYPE>                              YEAR
<FISCAL-YEAR-END>                          DEC-31-1996
<PERIOD-START>                             JAN-01-1996
<PERIOD-END>                               DEC-31-1996
<CASH>                                      34,475,060
<SECURITIES>                                62,552,706
<RECEIVABLES>                                4,334,780
<ALLOWANCES>                                         0
<INVENTORY>                                          0
<CURRENT-ASSETS>                            85,008,679
<PP&E>                                      53,501,625
<DEPRECIATION>                              19,203,782
<TOTAL-ASSETS>                             137,581,854
<CURRENT-LIABILITIES>                       12,048,462
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                        21,320
<OTHER-SE>                                 106,909,679
<TOTAL-LIABILITY-AND-EQUITY>               137,581,854
<SALES>                                              0
<TOTAL-REVENUES>                            24,113,962
<CGS>                                                0
<TOTAL-COSTS>                                        0
<OTHER-EXPENSES>                            55,598,116
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                             939,624
<INCOME-PRETAX>                            (32,423,778)
<INCOME-TAX>                                         0
<INCOME-CONTINUING>                        (32,423,778)
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                               (32,423,778)
<EPS-PRIMARY>                                    (1.33)
<EPS-DILUTED>                                    (1.24)
        


</TABLE>