Dupixent® (dupilumab) Positive Phase 3 Data in Children 1 to 11 Years of Age with Eosinophilic Esophagitis Published in the New England Journal of Medicine

Majority of patients in this age group with eosinophilic esophagitis (EoE) receiving Dupixent achieved histologic remission, with improvements sustained up to one year

Dupixent is the first and only treatment indicated for EoE in the U.S. for this age group

TARRYTOWN, N.Y. and PARIS, June 26, 2024 (GLOBE NEWSWIRE) -- Regeneron Pharmaceuticals, Inc., (NASDAQ: REGN) and Sanofi today announced the New England Journal of Medicine(NEJM) has published results from a positive Phase 3 trial for Dupixent^® (dupilumab) in children aged 1 to 11 years with eosinophilic esophagitis (EoE). The trial showed a greater proportion of those receiving weight-tiered higher dose Dupixent experienced significant improvements in many key disease measures of EoE, compared to placebo at week 16. Data from the trial were the basis for the U.S. Food and Drug Administration (FDA) Priority Review and approval of Dupixent in children aged 1 to 11 years with EoE weighing at least 15 kg, as well as for the regulatory submission that is currently under review by the European Medicines Agency for this age group.

EoE is a chronic, progressive disease associated with type 2 inflammation that is thought to be responsible for damaging the esophagus and impairing its function. Diagnosis is difficult, as symptoms can be mistaken for other conditions and there are delays in diagnosis. EoE can severely impact a child’s ability to eat and may also cause abdominal pain, trouble swallowing, heartburn, vomiting and failure to thrive. Continuous management of EoE may be needed to reduce the risk of complications and disease progression.

“The NEJM publication of these Phase 3 dupilumab results is a testament to the importance of these data and potential for dupilumab to change the standard of care for many young children with eosinophilic esophagitis. These children commonly experience feeding difficulties, food refusal and failure to thrive during a critical time of their growth and development,” said Mirna Chehade, MD, MPH, Mount Sinai Center for Eosinophilic Disorders, Ichan School of Medicine at Mount Sinai, New York, NY, and principal investigator of the trial. “These data showed weight-tiered higher dose dupilumab significantly improved key eosinophilic esophagitis histologic, endoscopic and cellular measures in children as young as 1 year old with sustained results for up to one year. These results reinforce the positive results seen in older patients with eosinophilic esophagitis and strengthen our understanding of IL-4 and IL-13 as key drivers of the type 2 inflammation underlying this disease.”

As published, a significantly greater proportion of children receiving either a weight-tiered higher or lower dose regimen of Dupixent achieved histologic remission at week 16 in Part A of the trial, compared with placebo. Additionally, those treated with higher dose Dupixent experienced significant improvements in disease severity assessed by endoscopic measures, with improvements sustained for up to one year. Those receiving lower dose Dupixent experienced improvements that were either comparable or numerically lower than the higher dose group. Dupixent also led to a numerical improvement in body weight for age percentile by week 16 that was sustained at one year, which was evaluated as an exploratory endpoint in Part A and a secondary endpoint in Part B.

Safety results were generally consistent with the known safety profile of Dupixent in adolescents and adults with EoE. Adverse events more commonly observed with Dupixent (³10%) in either weight-based dosing regimen versus placebo in the trial were COVID-19, nausea, injection site pain and headache during Part A. The long-term safety profile of Dupixent in children aged 1 to 11 years through Part B was similar to that observed during Part A. In Part B, one case of helminth infection was reported with Dupixent.

For patients in the U.S. with EoE weighing at least 15 kg., the FDA-approved dosage for Dupixent is 200 mg or 300mg every other week, or 300mg weekly, based on weight.

Dr. Mirna Chehade has served as a paid consultant for Regeneron and Sanofi and has received research grant funding from Regeneron.

About the Dupixent Pediatric Eosinophilic Esophagitis Trial
The Phase 3 randomized, double-blind, placebo-controlled trial evaluated the efficacy and safety of Dupixent in children aged 1 to 11 years with EoE. Part A enrolled 102 patients and evaluated Dupixent at a weight-tiered higher dose or lower dose regimen, compared to placebo, for 16 weeks. Part B was a 36-week extended active treatment period in which eligible children from Part A in the Dupixent group maintained their higher or lower dose level, while those in the placebo group switched to higher or lower dose Dupixent.

The primary endpoint was histologic remission at 16 weeks, and secondary endpoints included assessments of endoscopic and histopathologic measures of the severity of disease along with clinical signs and symptoms of EoE. Change in body weight-for-age percentile was evaluated as an exploratory endpoint in Part A and as a secondary endpoint in Part B. The trial is ongoing with a 108-week open-label extension period (Part C) to evaluate longer-term outcomes.

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 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, chronic rhinosinusitis with nasal polyposis (CRSwNP), eosinophilic esophagitis (EoE), prurigo nodularis, and chronic spontaneous urticaria (CSU) in different age populations. More than 850,000 patients are being treated with Dupixent globally.

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 portion of all original, FDA-approved or authorized fully human monoclonal antibodies. This includes REGEN-COV^® (casirivimab and imdevimab), Dupixent, Libtayo^® (cemiplimab-rwlc), Praluent^® (alirocumab), Kevzara^® (sarilumab), Evkeeza^® (evinacumab-dgnb) and Inmazeb^® (atoltivimab, maftivimab and odesivimab-ebgn).

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 spontaneous urticaria, chronic pruritus of unknown origin, chronic obstructive pulmonary disease with evidence of type 2 inflammation and bullous pemphigoid. 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. DUPIXENT is not used to treat sudden breathing problems. 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 polyposis (CRSwNP) in adults whose disease is not controlled. It is not known if DUPIXENT is safe and effective in children with chronic rhinosinusitis with nasal polyposis under 18 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.

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 https://mothertobaby.org/ongoing-study/dupixent/.
• 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 polyposis, eosinophilic esophagitis, or prurigo nodularis and also have asthma. Do not change or stop your corticosteroid medicine or other asthma medicine without talking to your healthcare provider. This may cause other symptoms that were controlled by the corticosteroid medicine or other asthma medicine 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. It is not known whether this is caused by DUPIXENT. Tell your healthcare provider right away if you have: rash, chest pain, worsening shortness of breath, a feeling of pins and needles or numbness of your arms or legs, or persistent fever.
• 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 Polyposis: 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.

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
We are an innovative global healthcare company, driven by one purpose: we chase the miracles of science to improve people’s lives. Our team, across the world, is dedicated to transforming the practice of medicine by working to turn the impossible into the possible. We provide potentially life-changing treatment options and life-saving vaccine protection to millions of people globally, while putting sustainability and social responsibility at the center of our ambitions.

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

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