Media Update: Sanofi and Regeneron provide update on Dupixent® (dupilumab) sBLA for Chronic Spontaneous Urticaria

Sanofi and Regeneron provide update on Dupixent® (dupilumab) sBLA for Chronic Spontaneous Urticaria

Paris and Tarrytown, N.Y. October 20, 2023. The U.S. Food and Drug Administration (FDA) has issued a Complete Response Letter (CRL) for the supplemental Biologics License Application (sBLA) for Dupixent® (dupilumab) in chronic spontaneous urticaria (CSU). CSU is an inflammatory skin condition, which causes sudden and debilitating hives and swelling on the skin.

The CRL states that additional efficacy data are required to support an approval; it did not identify any issues with safety or manufacturing. An ongoing clinical trial (Study C) continues to enroll patients, with results expected in late 2024 that are anticipated to provide the additional efficacy data.

Sanofi and Regeneron remain committed to working with the FDA to advance the study of Dupixent for patients living with CSU who are inadequately controlled by antihistamines.

The potential use of Dupixent in CSU is currently under clinical development, and the safety and efficacy have not been fully evaluated by any regulatory authority.

About the CSU Clinical Trial Program

The clinical trial program, known as LIBERTY-CUPID, includes Studies A, B and C, three Phase 3 randomized, double-blind, placebo-controlled trials evaluating the efficacy and safety of Dupixent in two different patient populations with uncontrolled CSU.

Study A evaluated Dupixent as an add-on therapy to standard-of-care H1 antihistamines compared to antihistamines alone in 138 patients with CSU aged 6 years and older who remained symptomatic despite antihistamine use and were not previously treated with omalizumab. Efficacy and safety data from Study A were the basis of the sBLA. Study B evaluated Dupixent in 108 patients with CSU aged 12 to 80 years who remained symptomatic despite standard-of-care treatment and were intolerant or incomplete responders to omalizumab, with results providing additional supporting data for the sBLA. Study C is an ongoing trial investigating Dupixent in the same population as Study A.

Dupixent 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 atopic dermatitis, asthma, chronic rhinosinusitis with nasal polyposis (CRSwNP), prurigo nodularis and EoE.

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 prurigo nodularis in different age populations. Dupixent is currently approved for one or more of these indications in more than 60 countries, including in Europe, the U.S. and Japan. More than 750,000 patients are being treated with Dupixent globally.

Dupilumab Development Program

Dupilumab is being jointly developed by Sanofi and Regeneron 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, Sanofi and Regeneron 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, 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.

Regeneron (NASDAQ: REGN) is a leading biotechnology company that invents, develops and commercializes life-transforming medicines for people with serious diseases. Founded and led for 35 years by physician-scientists, our unique ability to repeatedly and consistently translate science into medicine has led to numerous FDA-approved treatments and product candidates in development, almost all of which were homegrown in our laboratories. Regeneron’s medicines and pipeline are designed to help patients with eye diseases, allergic and inflammatory diseases, cancer, cardiovascular and metabolic diseases, hematologic conditions, infectious diseases and rare diseases.

Regeneron is accelerating and improving the traditional drug development process through its 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 additional information about Regeneron, please visit www.regeneron.com or follow Regeneron on LinkedIn.

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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