Late-breaking presentation at ACG 2023 showed histologic and endoscopic improvements were maintained with no new safety signals to week 52 with higher dose Dupixent in these children

Data reinforce the role of type 2 inflammation in EoE and the importance of targeting both IL-4 and IL-13 pathways

sBLA for Dupixent to treat children aged 1 to 11 years with EoE is under Priority Review in the U.S.; if approved, Dupixent would be the first and only FDA-approved treatment for these children with EoE

PARIS and TARRYTOWN, N.Y., Oct. 22, 2023 (GLOBE NEWSWIRE) -- Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) and Sanofi today announced that positive results from a Phase 3 trial evaluating the investigational use of Dupixent® (dupilumab) showed consistent efficacy and safety for up to one year (52 weeks) in children aged 1 to 11 years with eosinophilic esophagitis (EoE). These results represent the first analysis of longer-term data in this age group and will be featured in a late-breaking session on October 25 at the American College of Gastroenterology (ACG) 2023 Annual Scientific Meeting.

“Eosinophilic esophagitis, or EoE, is a chronic and debilitating condition that can impact children in their most vulnerable years of life, causing persistent difficulties with eating, abdominal pain, and/or failure to thrive,” said Mirna Chehade, M.D., MPH, Mount Sinai Center for Eosinophilic Disorders, Icahn School of Medicine at Mount Sinai, New York and principal investigator of the trial. “Dupilumab is the first and only therapeutic approved for adults and certain adolescents with EoE. Some children with EoE may have sub-optimal response to currently unapproved standard of care therapies, underscoring the need for treatments targeting key pathways driving inflammation in EoE. Data from this Phase 3 trial support the potential of dupilumab to treat EoE in children, with sustained efficacy and safety, which is particularly critical for these children.”

The late-breaking data to be presented at ACG feature results from children enrolled in the extended active treatment period (Part B) of a Phase 3 trial, following 16 weeks of Dupixent treatment or placebo in Part A of the trial. All children in Part B were treated with higher or lower dose Dupixent for an additional 36 weeks, providing up to 52 weeks of data.

In Part B, there were 37 patients who continued on higher dose Dupixent and 18 who switched from placebo to higher dose Dupixent. At one year, outcomes of secondary endpoints (as evaluated with descriptive statistics based on all observed data) among children who continued on higher dose Dupixent and for those switching from placebo to higher dose Dupixent was, respectively, as follows:

• 63% and 53% achieved histological disease remission
• 0.97 and 0.89 reduction from baseline in disease severity and 0.89 and 0.86 reduction from baseline in extent, respectively, as measured at the microscopic level in biopsy specimens
• 4.8 and 3.6-point reduction in abnormal endoscopic findings from baseline
• 0.30 and 0.47-point numerical improvement in caregiver reported pediatric signs and symptoms, as measured by PESQ-C
• 5.96 and 5.48 percentile increase in body weight for age percentile from baseline

Safety results in Part B of the trial were generally consistent with Part A and the known safety profile of Dupixent in its FDA-approved EoE indication for adult and adolescent patients aged 12 years and older who weigh at least 40 kg. AEs reported in ≥20% of patients who remained on higher dose Dupixent in Part B and those who switched from placebo to higher dose Dupixent in Part B, respectively, included: COVID-19 (n=11/37, n=5/18; all cases were mild or moderate and did not lead to study treatment discontinuation), injection site reaction (n=5/37, n=5/18), cough (n=3/37, n=4/18) and headache (n=3/37, n=4/18).

In September, the U.S. Food and Drug Administration accepted for Priority Review the supplemental Biologics License Application for higher dose Dupixent to treat children aged 1 to 11 years with EoE, with a target action date of January 31, 2024. This potential use of Dupixent in children with EoE aged 1 to 11 years is currently under clinical development, and its safety and efficacy have not been fully evaluated by any regulatory authority in this setting.

About Eosinophilic EsophagitisEoE is a chronic, progressive disease driven in part by type 2 inflammation that damages the esophagus and prevents it from working properly. In children, common symptoms of EoE include heartburn, vomiting, abdominal discomfort, trouble swallowing, food refusal and failure to thrive. These symptoms can impact growth and development and can cause food-related fear and anxiety, which can persist through adulthood. Dietary adjustments, which oftentimes include the elimination of food groups, are the standard treatment for EoE, as well as the use of treatments not approved for the disease, such as proton pump inhibitors and swallowed topical corticosteroids. Continuous treatment of EoE may be needed to reduce the risk of complications and disease recurrence.

About the Dupixent Pediatric Eosinophilic Esophagitis Trial The Phase 3, randomized, double-blind, placebo-controlled trial evaluated the efficacy and safety of Dupixent in young children aged 1 to 11 years with EoE, as determined by histological, endoscopic and patient- or caregiver-reported measures. At baseline, 98% of these patients had at least one co-existing type 2 inflammatory disease such as food allergy, allergic rhinitis, asthma and atopic dermatitis.

Part A, a 16-week, double-blind treatment period, enrolled 102 patients and evaluated Dupixent subcutaneously at either a higher dose or lower dose regimen based on weight (ranging from ≥5 kg to