Release Details

New late-breaking data at EAACI showed Dupixent outperformed Xolair across all primary and secondary efficacy endpoints of CRSwNP and in all asthma-related endpoints

Dupixent also outperformed Xolair in improving such key signs and symptoms as nasal polyp size and sense of smell in CRSwNP, and lung function and disease control in asthma, with rapid improvements seen as early as 4 weeks

Results reinforce the efficacy of Dupixent in treating both upper and lower respiratory diseases by targeting IL-4 and IL-13, two key drivers of type 2 inflammation

TARRYTOWN, N.Y. and PARIS, June 15, 2025 (GLOBE NEWSWIRE) -- Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) and Sanofi today presented positive results from the EVEREST Phase 4 trial in adults with severe chronic rhinosinusitis with nasal polyps (CRSwNP) and coexisting asthma. In the trial, Dupixent^® (dupilumab) outperformed Xolair^® (omalizumab) on all primary and secondary efficacy endpoints of CRSwNP, and in all asthma-related endpoints. The data are from the first-ever presented head-to-head respiratory trial with biologic medicines and were shared in a late-breaking oral presentation at the 2025 European Academy of Allergy and Clinical Immunology (EAACI) Annual Congress.

“Patients suffering from chronic rhinosinusitis with nasal polyps often live with the constant obstruction of their nasal passages that can lead to burdensome nasal congestion and loss of smell. What’s more, a majority of these individuals also have asthma that can substantially impact their quality of life,” said Eugenio De Corso, M.D., Ph.D., ENT Specialist, Otolaryngology, Head and Neck Surgery, Rhinology, A. Gemelli University Hospital Foundation, IRCSS, Rome, Italy, and lead investigator of the study. “EVEREST is the first-ever trial to demonstrate the superiority of Dupixent over Xolair on CRSwNP endpoints in patients with coexisting asthma, along with generally similar safety profiles. Together, these Dupixent outcomes provide important insights that will help guide patients and physicians through the treatment decision-making process.”

In the EVEREST trial, 360 adults with severe, uncontrolled CRSwNP and coexisting asthma were randomized to receive Dupixent 300 mg (n=181) every two weeks or a weight- and immunoglobulin E (IgE) level-based dosing regimen of Xolair (n=179) every two or four weeks. Both Dupixent and Xolair were added to background mometasone furoate nasal spray (MFNS).

Primary and secondary endpoint results in CRSwNP for patients treated with Dupixent compared to Xolair at 24 weeks were as follows, with differences seen as early as 4 weeks:

• 1.60-point superior reduction in nasal polyp size, a primary endpoint (p<0.0001^a)
• 8.0-point superior improvement in ability to identify different smells, a primary endpoint (p<0.0001^a). More patients on Dupixent improved above the anosmia threshold compared to Xolair.
• 0.58-point superior reduction in nasal congestion/obstruction, a key secondary endpoint (p<0.0001^a)
• 0.81-point superior improvement in loss of smell, a key secondary endpoint (p<0.0001^a)
• 1.74-point superior reduction in symptom severity (p<0.0001^a)
• 12.7-point difference in health-related quality of life (p<0.0001^b)
• 31.27-point difference in peak nasal inspiratory flow (p<0.0001^b)
• 1.87-point difference in overall severity of rhinosinusitis (p<0.0001^b)

Asthma endpoint results for patients treated with Dupixent compared to Xolair at 24 weeks were as follows, with differences seen as early as 4 weeks:

• 150 mL difference in lung function (pre-bronchodilator FEV₁; p=0.003^b)
• 0.48-point difference in asthma control (p<0.0001^b)
  

^aStatistically significant
^bNominally significant as the endpoint was not included in the multiplicity adjustment hierarchy

The safety results in the EVEREST trial were generally consistent with the known safety profile of Dupixent in its approved respiratory indications, with similar overall rates of adverse events (AEs) observed between Dupixent (64%) and Xolair (67%). Serious AEs were reported in 2% and 4% of patients treated with Dupixent and Xolair, respectively. Additionally, AEs leading to trial discontinuation were reported in 3% of Dupixent patients and 1% of Xolair patients.

About the Dupixent Phase 4 Trial
EVEREST is a randomized, double-blind Phase 4 trial comparing the efficacy and safety of Dupixent to Xolair in adults with severe, uncontrolled CRSwNP and coexisting mild, moderate or severe asthma. During the 24-week trial, patients received Dupixent 300 mg every two weeks or Xolair 75 to 600 mg every two or four weeks, which was added to background MFNS. Xolair dosing was determined based on body weight and serum total IgE levels as per the approved label. All endpoints were assessed at 24 weeks.

The primary endpoints assessed change from baseline in nasal polyp score (NPS; scale: 0-8) and the University of Pennsylvania Smell Identification Test (UPSIT; scale: 0-40). Secondary endpoints included change from baseline in nasal congestion (NC; scale: 0-3), loss of smell (LoS; scale: 0-3), total symptom score (TSS; scale: 0-9), Sino-Nasal Outcome Test-22 (SNOT-22; scale: 0-110), peak nasal inspiratory flow, and rhinosinusitis disease severity (visual analogue scale: 0-10 cm). Other endpoints assessed pre-bronchodilator forced expiratory volume over one second (pre-BD FEV₁) and the 7-item Asthma Control Questionnaire (ACQ-7; scale: 0-6).

About Dupixent
Dupixent, which was invented using Regeneron’s proprietary VelocImmune^® technology, is a fully human monoclonal antibody that inhibits the signaling of the interleukin-4 (IL-4) and interleukin-13 (IL-13) pathways and is not an immunosuppressant. The Dupixent development program has shown significant clinical benefit and a decrease in type 2 inflammation in Phase 3 trials, establishing that IL-4 and IL-13 are two of the key and central drivers of the type 2 inflammation that plays a major role in multiple related and often co-morbid diseases.

Dupixent has received regulatory approvals in more than 60 countries in one or more indications including certain patients with atopic dermatitis, asthma, CRSwNP, eosinophilic esophagitis (EoE), prurigo nodularis, chronic spontaneous urticaria (CSU) and chronic obstructive pulmonary disease (COPD) in different age populations. More than 1,000,000 patients are being treated with Dupixent globally.¹

About Regeneron’s VelocImmune Technology 
Regeneron's VelocImmune technology utilizes a proprietary genetically engineered mouse platform endowed with a genetically humanized immune system to produce optimized fully human antibodies. When Regeneron's co-Founder, President and Chief Scientific Officer George D. Yancopoulos was a graduate student with his mentor Frederick W. Alt in 1985, they were the first to envision making such a genetically humanized mouse, and Regeneron has spent decades inventing and developing VelocImmune and related VelociSuite^® technologies. Dr. Yancopoulos and his team have used VelocImmune technology to create a substantial proportion of all original, FDA-approved fully human monoclonal antibodies. This includes Dupixent^® (dupilumab), Libtayo^® (cemiplimab-rwlc), Praluent^® (alirocumab), Kevzara^® (sarilumab), Evkeeza^® (evinacumab-dgnb), Inmazeb^® (atoltivimab, maftivimab and odesivimab-ebgn) and Veopoz^® (pozelimab-bbfg). In addition, REGEN-COV^® (casirivimab and imdevimab) had been authorized by the FDA during the COVID-19 pandemic until 2024.

Dupilumab Development Program 
Dupilumab is being jointly developed by Regeneron and Sanofi under a global collaboration agreement. To date, dupilumab has been studied across more than 60 clinical trials involving more than 10,000 patients with various chronic diseases driven in part by type 2 inflammation. 

In addition to the currently approved indications, Regeneron and Sanofi are studying dupilumab in a broad range of diseases driven by type 2 inflammation or other allergic processes in Phase 3 trials, including chronic pruritus of unknown origin, bullous pemphigoid and lichen simplex chronicus. These potential uses of dupilumab are currently under clinical investigation, and the safety and efficacy in these conditions have not been fully evaluated by any regulatory authority. 

U.S. INDICATIONS 
DUPIXENT is a prescription medicine used:

• to treat adults and children 6 months of age and older with moderate-to-severe eczema (atopic dermatitis or AD) that is not well controlled with prescription therapies used on the skin (topical), or who cannot use topical therapies. DUPIXENT can be used with or without topical corticosteroids. It is not known if DUPIXENT is safe and effective in children with atopic dermatitis under 6 months of age.
• with other asthma medicines for the maintenance treatment of moderate-to-severe eosinophilic or oral steroid dependent asthma in adults and children 6 years of age and older whose asthma is not controlled with their current asthma medicines. DUPIXENT helps prevent severe asthma attacks (exacerbations) and can improve your breathing. DUPIXENT may also help reduce the amount of oral corticosteroids you need while preventing severe asthma attacks and improving your breathing. It is not known if DUPIXENT is safe and effective in children with asthma under 6 years of age.
• with other medicines for the maintenance treatment of chronic rhinosinusitis with nasal polyps (CRSwNP) in adults and children 12 years of age and older whose disease is not controlled. It is not known if DUPIXENT is safe and effective in children with chronic rhinosinusitis with nasal polyps under 12 years of age.
• to treat adults and children 1 year of age and older with eosinophilic esophagitis (EoE), who weigh at least 33 pounds (15 kg). It is not known if DUPIXENT is safe and effective in children with eosinophilic esophagitis under 1 year of age, or who weigh less than 33 pounds (15 kg).
• to treat adults with prurigo nodularis (PN). It is not known if DUPIXENT is safe and effective in children with prurigo nodularis under 18 years of age.
• with other medicines for the maintenance treatment of adults with inadequately controlled chronic obstructive pulmonary disease (COPD) and a high number of blood eosinophils (a type of white blood cell that may contribute to your COPD). DUPIXENT is used to reduce the number of flare-ups (the worsening of your COPD symptoms for several days) and can improve your breathing. It is not known if DUPIXENT is safe and effective in children with chronic obstructive pulmonary disease under 18 years of age.
• to treat adults and children 12 years of age and older with chronic spontaneous urticaria (CSU) who continue to have hives that are not controlled with H1 antihistamine treatment. It is not known if DUPIXENT is safe and effective in children with chronic spontaneous urticaria under 12 years of age, or who weigh less than 66 pounds (30 kg).
  

DUPIXENT is not used to relieve sudden breathing problems and will not replace an inhaled rescue medicine.

DUPIXENT is not used to treat any other forms of hives (urticaria).

IMPORTANT SAFETY INFORMATION

Do not use if you are allergic to dupilumab or to any of the ingredients in DUPIXENT^®.

Before using DUPIXENT, tell your healthcare provider about all your medical conditions, including if you:

• have eye problems.
• have a parasitic (helminth) infection.
• are scheduled to receive any vaccinations. You should not receive a “live vaccine” right before and during treatment with DUPIXENT.
• are pregnant or plan to become pregnant. It is not known whether DUPIXENT will harm your unborn baby.
  • A pregnancy registry for women who take DUPIXENT during pregnancy collects information about the health of you and your baby. To enroll or get more information call 1-877-311-8972 or go to .
• are breastfeeding or plan to breastfeed. It is not known whether DUPIXENT passes into your breast milk.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Especially tell your healthcare provider if you are taking oral, topical, or inhaled corticosteroid medicines; have asthma and use an asthma medicine; or have atopic dermatitis, chronic rhinosinusitis with nasal polyps, eosinophilic esophagitis, prurigo nodularis, chronic obstructive pulmonary disease, or chronic spontaneous urticaria, and also have asthma. Do not change or stop your other medicines, including corticosteroid medicine or other asthma medicine, without talking to your healthcare provider. This may cause other symptoms that were controlled by those medicines to come back.

DUPIXENT can cause serious side effects, including:

• Allergic reactions. DUPIXENT can cause allergic reactions that can sometimes be severe. Stop using DUPIXENT and tell your healthcare provider or get emergency help right away if you get any of the following signs or symptoms: breathing problems or wheezing, swelling of the face, lips, mouth, tongue or throat, fainting, dizziness, feeling lightheaded, fast pulse, fever, hives, joint pain, general ill feeling, itching, skin rash, swollen lymph nodes, nausea or vomiting, or cramps in your stomach-area.
• Eye problems. Tell your healthcare provider if you have any new or worsening eye problems, including eye pain or changes in vision, such as blurred vision. Your healthcare provider may send you to an ophthalmologist for an exam if needed
• Inflammation of your blood vessels. Rarely, this can happen in people with asthma who receive DUPIXENT. This may happen in people who also take a steroid medicine by mouth that is being stopped or the dose is being lowered. Tell your healthcare provider right away if you have: rash, chest pain, worsening shortness of breath, brown or dark colored urine, persistent fever, or a feeling of pins and needles or numbness of your arms or legs.
• Psoriasis. This can happen in people with atopic dermatitis and asthma who receive DUPIXENT. Tell your healthcare provider about any new skin symptoms. Your healthcare provider may send you to a dermatologist for an examination if needed.
• Joint aches and pain. Some people who use DUPIXENT have had trouble walking or moving due to their joint symptoms, and in some cases needed to be hospitalized. Tell your healthcare provider about any new or worsening joint symptoms. Your healthcare provider may stop DUPIXENT if you develop joint symptoms.
  

The most common side effects include:

• Eczema: injection site reactions, eye and eyelid inflammation, including redness, swelling, and itching, sometimes with blurred vision, dry eye, cold sores in your mouth or on your lips, and high count of a certain white blood cell (eosinophilia).
• Asthma: injection site reactions, high count of a certain white blood cell (eosinophilia), pain in the throat (oropharyngeal pain), and parasitic (helminth) infections.
• Chronic Rhinosinusitis with Nasal Polyps: injection site reactions, eye and eyelid inflammation, including redness, swelling, and itching, sometimes with blurred vision, high count of a certain white blood cell (eosinophilia), gastritis, joint pain (arthralgia), trouble sleeping (insomnia), and toothache.
• Eosinophilic Esophagitis: injection site reactions, upper respiratory tract infections, cold sores in your mouth or on your lips, and joint pain (arthralgia).
• Prurigo Nodularis: eye and eyelid inflammation, including redness, swelling, and itching, sometimes with blurred vision, herpes virus infections, common cold symptoms (nasopharyngitis), dizziness, muscle pain, and diarrhea.
• Chronic Obstructive Pulmonary Disease: injection site reactions, common cold symptoms (nasopharyngitis), high count of a certain white blood cell (eosinophilia), viral infection, back pain, inflammation inside the nose (rhinitis), diarrhea, gastritis, joint pain (arthralgia), toothache, headache, and urinary tract infection.
• Chronic Spontaneous Urticaria: injection site reactions.
  

Tell your healthcare provider if you have any side effect that bothers you or that does not go away. These are not all the possible side effects of DUPIXENT. Call your doctor for medical advice about side effects. You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch, or call 1-800-FDA-1088.

Use DUPIXENT exactly as prescribed by your healthcare provider. It’s an injection given under the skin (subcutaneous injection). Your healthcare provider will decide if you or your caregiver can inject DUPIXENT. Do not try to prepare and inject DUPIXENT until you or your caregiver have been trained by your healthcare provider. In children 12 years of age and older, it’s recommended DUPIXENT be administered by or under supervision of an adult. In children 6 months to less than 12 years of age, DUPIXENT should be given by a caregiver.

Please see accompanying full Prescribing Information including Patient Information.

About Regeneron
Regeneron (NASDAQ: REGN) is a leading biotechnology company that invents, develops and commercializes life-transforming medicines for people with serious diseases. Founded and led by physician-scientists, our unique ability to repeatedly and consistently translate science into medicine has led to numerous approved treatments and product candidates in development, most of which were homegrown in our laboratories. Our medicines and pipeline are designed to help patients with eye diseases, allergic and inflammatory diseases, cancer, cardiovascular and metabolic diseases, neurological diseases, hematologic conditions, infectious diseases, and rare diseases.

Regeneron pushes the boundaries of scientific discovery and accelerates drug development using our proprietary technologies, such as VelociSuite, which produces optimized fully human antibodies and new classes of bispecific antibodies. We are shaping the next frontier of medicine with data-powered insights from the Regeneron Genetics Center^® and pioneering genetic medicine platforms, enabling us to identify innovative targets and complementary approaches to potentially treat or cure diseases.

For more information, please visit www.Regeneron.com or follow Regeneron on LinkedIn, Instagram, Facebook or X.

About Sanofi 
Sanofi is an R&D driven, AI-powered biopharma company committed to improving people’s lives and delivering compelling growth. We apply our deep understanding of the immune system to invent medicines and vaccines that treat and protect millions of people around the world, with an innovative pipeline that could benefit millions more. Our team is guided by one purpose: we chase the miracles of science to improve people’s lives; this inspires us to drive progress and deliver positive impact for our people and the communities we serve, by addressing the most urgent healthcare, environmental, and societal challenges of our time.

Sanofi is listed on EURONEXT: SAN and NASDAQ: SNY.

Regeneron Forward-Looking Statements and Use of Digital Media 
This press release includes forward-looking statements that involve risks and uncertainties relating to future events and the future performance of Regeneron Pharmaceuticals, Inc. (“Regeneron” or the “Company”), and actual events or results may differ materially from these forward-looking statements. Words such as “anticipate,” “expect,” “intend,” “plan,” “believe,” “seek,” “estimate,” variations of such words, and similar expressions are intended to identify such forward-looking statements, although not all forward-looking statements contain these identifying words. 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¹ Data on File

Source: Regeneron Pharmaceuticals, Inc.