• Dupixent 300 mg weekly showed significant histological disease remission and improvement in symptoms of the disease compared to placebo
• Improvements were sustained for up to one year in patients aged 12 years and older with eosinophilic esophagitis (EoE)
• Dupixent is the first and only targeted medicine indicated in the U.S. to treat EoE patients aged 12 and older weighing at least 40 kg

TARRYTOWN, N.Y. and PARIS, Dec. 21, 2022 /PRNewswire/ -- Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) and Sanofi today announced the New England Journal of Medicine has published results from a positive Phase 3 trial showing adults and adolescents treated with Dupixent^® (dupilumab) 300 mg weekly experienced significant improvements in signs and symptoms of eosinophilic esophagitis (EoE), which were sustained for up to one year.

EoE is a chronic, progressive inflammatory disease that damages the esophagus and prevents it from working properly. These data formed the basis for the U.S. Food and Drug Administration (FDA) approval of Dupixent in May 2022, making it the first and only medicine indicated to treat patients with EoE aged 12 years and older, weighing at least 40 kg. These Phase 3 data have been submitted to the European Medicines Agency (EMA) to support regulatory approval for adults and adolescents with EoE. The EMA's Committee for Medicinal Products for Human Use recently adopted a positive opinion recommending approval, with a final decision expected in the coming months.

"The publication of these Phase 3 results in the New England Journal of Medicine reinforces the impact of the clinical trial data. These data showed dupilumab 300 mg weekly substantially decreased patient symptoms of difficulty swallowing, and led to histological disease remission and improvements in the endoscopic appearance of the esophagus, as compared to placebo," said Evan S. Dellon, M.D., M.P.H., Professor of Gastroenterology and Hepatology at the University of North Carolina School of Medicine and co-principal investigator of the trial. "These data also underscore the role of inhibiting the IL-4 and IL-13 pathways in eosinophilic esophagitis with dupilumab, adding to our growing knowledge of this poorly understood disease."

As published, patients received Dupixent 300 mg either weekly or every two weeks in the Phase 3 trial. Patients receiving Dupixent weekly experienced improvement in the ability to swallow and achieved histological disease remission. Additionally, these patients experienced improved anatomic, cellular, molecular and health-related quality of life measures, with improvements in signs and symptoms of EoE sustained for up to one year. Patients treated with Dupixent every two weeks experienced histological disease remission but did not experience improvement in the ability to swallow. The current FDA-approved dosage for Dupixent as a treatment for children and adults aged 12 years and older with EoE, weighing at least 40 kg, is 300 mg weekly.

The safety results were generally consistent with the known safety profile of Dupixent in its approved indications. Adverse events (≥5%) that were more commonly observed with Dupixent included injection site reactions, nasopharyngitis and rash.

About Eosinophilic Esophagitis
EoE is a chronic, progressive inflammatory disease that damages the esophagus and prevents it from working properly. The results seen with Dupixent in adults and adolescents with EoE demonstrate that interleukin-4 (IL-4) and interleukin-13 (IL-13) are key and central drivers of the type 2 inflammation underlying this disease. For people with EoE, swallowing even small amounts of food can be a painful and worrisome choking experience. They are often left to contend with the frustration and anxiety of a constantly evolving list of foods to avoid, a poor quality of life and a higher risk of depression. In cases where EoE causes the esophagus to narrow, forced and potentially painful dilation (physical expansion) of the esophagus may be needed. In severe cases, a feeding tube may be the only option to ensure proper caloric intake and adequate nutrition. Of the approximately 209,000 patients aged 12 years and older living with EoE in the U.S. who are currently treated with therapies not specifically approved for the disease, about 42,000 continue to experience symptoms despite multiple treatments.

About the Dupixent Eosinophilic Esophagitis Trial
The Phase 3 randomized, double-blind, placebo-controlled trial evaluated the efficacy and safety of Dupixent in patients aged 12 years and older with EoE in three parts. Part A enrolled 81 patients and evaluated Dupixent 300 mg weekly for 24 weeks. Part B enrolled 240 patients and evaluated Dupixent 300 mg weekly and every two weeks for 24 weeks. Parts A and B were designed similarly and consisted of separate patient groups. All patients in Parts A and B had an option to participate in Part C for an additional 28 weeks, for up to 52 weeks of Dupixent treatment. Part C enrolled 77 patients from Part A.

At 24 weeks, the co-primary endpoints in Parts A and B assessed patient-reported measures of difficulty swallowing and esophageal inflammation. The secondary endpoints included assessments of histopathologic measures of the severity and extent of additional histological measures in the esophagus, and other measures. In Part C, all primary and secondary endpoints assessed in Parts A and B were assessed as secondary endpoints at 52 weeks.

About Dupixent
Dupixent, which was invented using Regeneron's proprietary VelocImmune^® technology, is a fully human monoclonal antibody that inhibits the signaling of the IL-4 and 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. These diseases include approved indications for Dupixent such as asthma, atopic dermatitis, chronic rhinosinusitis with nasal polyposis (CRSwNP), EoE and prurigo nodularis (PN).

Dupixent has received regulatory approvals in one or more countries around the world for use in certain patients with atopic dermatitis, asthma, CRSwNP, EoE or PN in different age populations. Dupixent is currently approved across these indications in the U.S. and for one or more of these indications in more than 60 countries, including in the European Union and Japan. More than 500,000 patients have been 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 approximately one in five 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 pediatric EoE, hand and foot atopic dermatitis, chronic inducible urticaria-cold, chronic spontaneous urticaria, chronic pruritis of unknown origin, chronic obstructive pulmonary disease with evidence of type 2 inflammation, chronic rhinosinusitis without nasal polyposis, allergic fungal rhinosinusitis, allergic bronchopulmonary aspergillosis 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 12 years of age and older, who weigh at least 88 pounds (40 kg), with eosinophilic esophagitis (EoE). It is not known if DUPIXENT is safe and effective in children with eosinophilic esophagitis under 12 years of age and who weigh at least 88 pounds (40 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, 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 is a leading biotechnology company that invents, develops and commercializes life-transforming medicines for people with serious diseases. Founded and led for nearly 35 years by physician-scientists, our unique ability to repeatedly and consistently translate science into medicine has led to nine FDA-approved treatments and numerous product candidates in development, almost all 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, pain, hematologic conditions, infectious diseases and rare diseases.

Regeneron is accelerating and improving the traditional drug development process through our proprietary VelociSuite^® technologies, such as VelocImmune^®, which uses unique genetically humanized mice to produce optimized fully human antibodies and bispecific antibodies, and through ambitious research initiatives such as the Regeneron Genetics Center, which is conducting one of the largest genetics sequencing efforts in the world.

For more information, please visit www.Regeneron.com or follow @Regeneron on Twitter.

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 some 100 countries, 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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