Sanofi and Regeneron Announce Positive Study Results for Dupixent (dupilumab) in Patients With Moderate-to-Severe Atopic Dermatitis Late-breaking oral abstract of Phase 3 CAFÉ study presented at the

Sanofi and Regeneron Announce Positive Study Results for

Dupixent (dupilumab) in Patients With Moderate-to-Severe

Late-breaking oral abstract of Phase 3 CAF study presented at the

26th European Academy of Dermatology and Venereology (EADV) Congress

Paris, France and Tarrytown, N.Y. September 16, 2017 Sanofi and Regeneron Pharmaceuticals, Inc. announced today positive results

from the Phase 3 CAF study of Dupixent (dupilumab) in adults with moderate-to-severe atopic dermatitis (AD) who are inadequately controlled with or intolerant to the broad

immunosuppressant drug cyclosporine A (CSA), or when this treatment is medically inadvisable.1 In the study, Dupixent with topical corticosteroids (TCS) significantly improved measures of overall

disease severity, skin clearing, itching, and patient reported quality of life measures. CSA is approved for the treatment of AD in most European countries and Japan; it is not approved in the U.S. for this use. The results of this study are being

presented at the European Academy of Dermatology and Venerology (EADV) Congress in Geneva, Switzerland.

The primary endpoint of the study was the

proportion of patients that achieved a 75 percent or greater improvement in the Eczema Area and Severity Index (EASI-75) score at 16 weeks from baseline. EASI is a tool used to measure the extent and severity of the disease. Fifty-nine percent of

patients who received Dupixent weekly with TCS, and 63 percent of patients who received Dupixent every two weeks with TCS achieved EASI-75, compared to 30 percent of those patients who received placebo with TCS (p less than 0.0001).

The mean percent change improvement in EASI from baseline at 16 weeks (a secondary endpoint) was 78 percent and 80 percent for patients who received Dupixent

weekly or every two weeks with TCS, respectively, compared to 47 percent for those who received placebo plus TCS (p less than 0.0001).

moderate-to-severe atopic dermatitis, some patients stop cyclosporine therapy due to intolerance or lack of efficacy, or are not candidates because of other medical conditions or contraindicated medications, said Dr. Marjolein De

Bruin-Weller, Dermatologist, National Expertise Center for Atopic Dermatitis, University Medical Center Utrecht. In the CAF study, Dupixent with topical corticosteroids significantly improved overall measures of disease severity

including lesions, itch, quality of life measures and symptoms of anxiety and depression in these patients. The safety profile in this study was consistent with three previous positive Dupixent Phase 3 studies in moderate-to-severe atopic

Other secondary endpoints of the study included measures of the impact of Dupixent on the persistent itch caused

by the disease, quality of life measures, and symptoms of anxiety and depression. The results for these secondary endpoints at 16 weeks include:

No new adverse events were reported in the study. The proportion of patients reporting an adverse event was similar among the treatment arms. Conjunctivitis

was more frequent in patients who received Dupixent with TCS, with 16 percent and 28 percent reported in patients who received Dupixent weekly or every two weeks with TCS, respectively, compared to 11 percent for patients who received placebo with

TCS. Injection site reactions were reported in 11 percent and 4 percent among patients who received DUPIXENT with TCS weekly or every two weeks, respectively, compared to 5 percent for patients who received placebo with TCS. Skin infections were

reported in 4 percent and 2 percent among patients who received Dupixent weekly or every two weeks with TCS, respectively, compared to 8 percent for patients who received placebo with TCS.

A total of 325 patients in Europe were randomized into three treatment groups in the 16-week study to receive either Dupixent 300 mg weekly with TCS, Dupixent

300 mg every two weeks with TCS or placebo with TCS.

About Dupixent (dupilumab)

Dupixent is a human monoclonal antibody that is designed to simultaneously inhibit overactive signaling of IL-4 and IL-13 cytokines.2,3 In addition to moderate-to-severe atopic dermatitis, Sanofi and Regeneron are studying dupilumab in a broad range of clinical development programs including uncontrolled persistent asthma (phase

3), nasal polyps (phase 3) and eosinophilic esophagitis (phase 2). These potential uses are investigational and the safety and efficacy have not been evaluated by any regulatory authority. Dupilumab is being jointly developed by Sanofi and Regeneron

under a global collaboration agreement.

In March 2017, the U.S. Food and Drug Administration (FDA) approved Dupixent (dupilumab) in the U.S. for the treatment of adults with moderate-to-severe atopic dermatitis whose disease is not adequately controlled with topical prescription therapies, or when those

therapies are not advisable.4 Dupixent is given as one, 300 mg injection under the skin (subcutaneous injection) every 2 weeks after an initial loading dose (600 mg). The European Commission (EC)

is expected to adopt a final decision on the Marketing Authorization Application (MAA) for Dupixent in the European Union, following the Committee for Medicinal Products for Human Use (CHMP) adopting a positive opinion on July 21, 2017.

About Atopic Dermatitis

Atopic dermatitis, a form of

eczema, is a chronic inflammatory disease with symptoms often appearing as a rash on the skin.5,6,7,8 Moderate-to-severe atopic dermatitis is characterized by rashes often covering much of the

body, and can include intense, persistent itching and skin dryness, cracking, redness, crusting, and oozing.9 Itch is one of the most burdensome symptoms for patients and can be debilitating.10 In addition, patients with moderate-to-severe atopic dermatitis experience a substantial burden of disease, including skin lesions, intense pruritus, and impact on quality of life components, such

as sleep and symptoms of anxiety and depression.10,11

IMPORTANT SAFETY INFORMATION for U.S.

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:

your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins and herbal supplements. If you have asthma and are taking asthma medicines, do not change or stop your asthma medicine without

talking to your healthcare provider.

Dupixent can cause serious side effects, including:

The most common side effects include injection site reactions, eye and eyelid inflammation, including redness, swelling and itching, and cold sores in

your mouth or on your lips.

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 may report side effects to FDA at 1-800-FDA-1088.

Dupixent exactly as prescribed. If your healthcare provider decides that you or a caregiver can give Dupixent injections, you or your caregiver should receive training on the right way to prepare and inject Dupixent. Do not try to inject

Dupixent until you have been shown the right way by your healthcare provider.

Please click here for the full Prescribing Information. The

patient information is available here.

Sanofi, a global healthcare leader, discovers, develops and distributes therapeutic solutions focused on patients needs. Sanofi is organized into five

global business units: Diabetes and Cardiovascular, General Medicines and Emerging Markets, Sanofi Genzyme, Sanofi Pasteur and Consumer Healthcare. Sanofi is listed in Paris (EURONEXT: SAN) and in New York (NYSE: SNY).

Sanofi Genzyme focuses on developing specialty treatments for debilitating diseases that are often difficult to diagnose and treat, providing hope to patients

About Regeneron Pharmaceuticals, Inc.

Regeneron (NASDAQ: REGN) is a leading biotechnology company that invents life-transforming medicines for people with serious diseases. Founded and led for

nearly 30 years by physician-scientists, our unique ability to repeatedly and consistently translate science into medicine has led to six FDA-approved treatments and over a dozen product candidates in development, all of which were homegrown in our

laboratories. Our medicines and pipeline are designed to help patients with eye disease, heart disease, allergic and inflammatory diseases, pain, cancer, and infectious and rare diseases.

Regeneron is accelerating and improving the traditional drug development process through its unique

VelociSuite technologies and ambitious initiatives such as The Regeneron Genetics Center, one of the largest genetics sequencing efforts in the world.

For additional information about the company, please visit www.regeneron.com or follow @Regeneron on Twitter.

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identifying words. These statements concern, and these risks and uncertainties include, among others, the nature, timing, and possible success and therapeutic applications of Regeneron s products, product candidates, and research and clinical

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other potential indications; the extent to which the results from the research and development programs conducted by Regeneron or its collaborators may be replicated in later studies and lead to therapeutic applications; unforeseen safety issues and

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