Positive Phase 3 Dupixent® (dupilumab) data in children 6 months to 5 years with moderate-to-severe atopic dermatitis featured in RAD 2021 late-breaking session

Positive Phase 3 Dupixent® (dupilumab) data in children 6 months to 5 years with moderate-to-severe atopic dermatitis featured in RAD 2021 late-breaking session 

• Dupixent significantly improved skin clearance and reduced overall disease severity and itch in a Pivotal trial that met all primary and secondary endpoints
• Data reinforce well-established safety profile of Dupixent
• Global regulatory filings are planned in the coming months starting with the U.S. by the end of 2021

PARIS and TARRYTOWN, N.Y. – December 13, 2021 – Positive Phase 3 results show adding Dupixent^® (dupilumab) to standard-of-care topical corticosteroids (TCS) significantly improved skin clearance and reduced overall disease severity and itch in infants and children aged 6 months to 5 years with uncontrolled moderate-to-severe atopic dermatitis. These data will be presented today in a late-breaking session at the 2021 Revolutionizing Atopic Dermatitis Conference (RAD 2021).

“One of most challenging aspects of my job as a physician is having limited treatment options to help babies and young children suffering from moderate-to-severe atopic dermatitis, which can disrupt their ability to fully thrive in these early years of life,” says Amy S. Paller, M.D, Walter J. Hamlin Professor and Chair of Dermatology and Professor of Pediatrics at Northwestern University Feinberg School of Medicine, and principal investigator of the trial. “These results show dupilumab can significantly improve the signs and overall severity of atopic dermatitis in children as young as 6 months. Safety is of paramount importance when treating children at such a young age. We are encouraged that these data show a safety profile consistent with what has been seen in other age groups. We will continue to follow these patients for up to 5 years in an open-label trial.”

Eighty-five to 90% of patients with atopic dermatitis develop symptoms before the age of 5, which can often continue through adulthood. Symptoms include intense, persistent itch and skin lesions that cover much of the body (58% on average for the patients in this trial at baseline), resulting in skin dryness, cracking, redness or darkening, and crusting and oozing, along with increased risk of skin infections. Moderate-to-severe atopic dermatitis may also significantly impact the quality of life of a young child, their parents and caregivers. In addition, the underlying type 2 inflammation involved in atopic dermatitis can contribute to the development of other diseases like asthma and certain allergies, that may also appear throughout a person's life.

Topline results from the randomized, placebo-controlled pivotal trial, which met all primary and secondary endpoints, were announced in August 2021. Data presented at RAD 2021 showed that at 16 weeks, patients who added Dupixent to low-potency TCS experienced the following, compared to TCS alone (placebo):

• 28% achieved clear or almost-clear skin compared to 4% with placebo (p<0.0001), the primary endpoint.
• 53% achieved 75% or greater improvement in overall disease severity from baseline compared to 11% with placebo (p<0.0001), the co-primary endpoint outside of the U.S.
• 49% average improvement from baseline in itch compared to 2% improvement with placebo (p<0.0001).
• 70% average improvement from baseline in overall disease severity (EASI) compared to 20% improvement with placebo (p<0.0001).

The safety profile observed in the randomized, placebo-controlled trial was consistent with the well-established safety profile of Dupixent in adults, adolescents and children 6 years and older with moderate-to-severe atopic dermatitis. Overall rates of adverse events (AEs) were 64% for Dupixent and 74% for placebo. Most common AEs and AEs of special interest included nasopharyngitis (8% Dupixent, 9% placebo), upper respiratory tract infection (6% Dupixent, 8% placebo), conjunctivitis (5% Dupixent, 0% placebo), herpes viral infections (6% Dupixent, 5% placebo).

These results will form the basis of global regulatory submissions for this age group, beginning with the U.S. in 2021 and European Union in the first half of 2022.

Additionally, long-term data from the Phase 3 trial in patients aged 6 to 11 years with moderate-to-severe atopic dermatitis will also be presented in a late-breaking session. Efficacy and safety results at one year were consistent with the known profile of Dupixent in atopic dermatitis.

The data from these trials add to the extensive LIBERTY AD clinical program – the largest Phase 3 clinical trial program in atopic dermatitis, involving approximately 3,500 infants, children, adolescents and adults to date.

Dupixent is the first biologic medicine to demonstrate positive results in this young patient population. The efficacy and safety of Dupixent in children below the age of 6 years have not been fully evaluated by any regulatory authority.

About the Dupixent Trial

LIBERTY AD PRESCHOOL is a two-part Phase 2/3 trial. The Phase 3 randomized, double-blind, placebo-controlled part of the trial (Part B) evaluated the efficacy and safety of Dupixent added to standard-of-care low-potency TCS compared to low-potency TCS alone (placebo) in 162 children aged 6 months to 5 years with uncontrolled moderate-to-severe atopic dermatitis.

The primary endpoints assessed the proportion of patients achieving an Investigator's Global Assessment (IGA) score of 0 (clear) or 1 (almost clear) and 75% improvement in Eczema Area and Severity Index (EASI-75) at week 16. EASI measures extent and severity of the disease. Itch was assessed using a caregiver-reported 0 to 10 Numerical Rating Scale. Patients treated with Dupixent received either 200 mg (for children weighing ≥5 to <15 kg) or 300 mg (for children weighing ≥15 to <30 kg) every four weeks.

In total, there were 162 patients in the trial (83 Dupixent, 79 in the placebo), the average age was 3.8 years and 61% were male. Approximately 12% of patients were Latino/Hispanic and 19% were Black/African American. At the start of the trial 77% of patients had severe disease and 29% had previously used systemic immunosuppressants for their atopic dermatitis and on average, patients entered the trial with atopic dermatitis covering 58% of their body. Furthermore, 81% of these patients had at least one concurrent type 2 inflammatory and/or allergic condition such as allergic rhinitis and asthma.

Part B of the Phase 3 trial was informed by Part A, which was an open-label, single-ascending-dose, sequential cohort Phase 2 trial designed to assess the pharmacokinetics and safety of Dupixent in children aged 6 months to 5 years with uncontrolled severe atopic dermatitis.

Children who completed Part A or Part B of the trial were eligible to enroll in an open-label extension trial to assess the safety and efficacy of long-term treatment with Dupixent in this age group for an additional five years.

About Dupixent

Dupixent is a fully human monoclonal antibody that inhibits the signaling of the interleukin-4 (IL-4) and interleukin-13 (IL-13) pathways. Dupixent is not an immunosuppressant and does not require lab monitoring. IL-4 and IL-13 are key and central drivers of the type 2 inflammation that plays a major role in atopic dermatitis, asthma and chronic rhinosinusitis with nasal polyposis (CRSwNP).

Dupixent is currently approved in the U.S., Europe, Japan and other countries around the world for use in specific patients with moderate-to-severe atopic dermatitis, as well as certain patients with asthma or CRSwNP in different age populations. Dupixent is also approved in one or more of these indications in more than 60 countries around the world and more than 300,000 patients have been treated 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 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, including pediatric atopic dermatitis (6 months to 5 years of age, Phase 3), chronic obstructive pulmonary disease with evidence of type 2 inflammation (Phase 3), eosinophilic esophagitis (Phase 3), bullous pemphigoid (Phase 3), prurigo nodularis (Phase 3), chronic spontaneous urticaria (Phase 3), chronic inducible urticaria-cold (Phase 3), chronic rhinosinusitis without nasal polyposis (Phase 3), allergic fungal rhinosinusitis (Phase 3), allergic bronchopulmonary aspergillosis (Phase 3) and peanut allergy (Phase 2). 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.

About Regeneron

Regeneron (NASDAQ: REGN) is a leading biotechnology company that invents life-transforming medicines for people with serious diseases. Founded and led for over 30 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 additional information about the company, please visit www.regeneron.com or follow @Regeneron on Twitter.

About Sanofi

Sanofi is dedicated to supporting people through their health challenges. We are a global biopharmaceutical company focused on human health. We prevent illness with vaccines, provide innovative treatments to fight pain and ease suffering. We stand by the few who suffer from rare diseases and the millions with long-term chronic conditions.

With more than 100,000 people in 100 countries, Sanofi is transforming scientific innovation into healthcare solutions around the globe.

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