Medical Information

Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) and Sanofi today announced positive detailed results from a second Phase 3 trial that showed Dupixent® (dupilumab) 300 mg weekly significantly improved the signs and symptoms of eosinophilic esophagitis (EoE) at 24 weeks compared to placebo in patients 12 years and older. These pivotal data will be presented today at the 2022 American Academy of Allergy, Asthma and Immunology (AAAAI) Annual Meeting during a late-breaking oral abstract session.
"Eosinophilic esophagitis can greatly impact a person's ability to eat normally, and physicians rely on invasive medical procedures to monitor and, in more serious cases, stretch the esophagus," 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.

"Currently, there are no FDA-approved treatment options that address the underlying drivers of this disease. The data from this trial showed dupilumab taken weekly not only improved patients' ability to swallow, but also reduced markers of type 2 inflammation in the esophagus, indicating its potential to address a major underlying cause of eosinophilic esophagitis."
Topline results from the Dupixent 300 mg weekly arm of the trial, which enrolled 80 patients in the Dupixent group and 79 patients in the placebo group, were announced in October 2021 and confirm results from the first Phase 3 trial. The co-primary endpoints at 24 weeks assessed patient-reported measures of difficulty swallowing (change from baseline in the 0-84 Dysphagia Symptom Questionnaire, or DSQ), and esophageal inflammation (proportion of patients achieving histological disease remission, defined as peak esophageal intraepithelial eosinophil count of ≤6 eos/high power field [hpf]).
Data presented at the 2022 AAAAI Annual Meeting showed that patients treated with Dupixent 300 mg weekly experienced the following changes by week 24 compared to placebo:

64% reduction in disease symptoms from baseline compared to 41% for placebo (p=0.0008). Patients receiving Dupixent experienced a 23.78 point improvement on the DSQ, compared to a 13.86 point improvement for placebo (p<0.0001); baseline DSQ scores were approximately 38 and 36 points, respectively.
Nearly 10 times as many patients receiving Dupixent achieved histological disease remission: 59% of patients achieved histological disease remission compared to 6% of patients receiving placebo (p<0.0001); mean baseline peak levels were 89 and 84 eos/hpf, respectively.
The safety results of the trial were generally consistent with the known safety profile of Dupixent in its approved indications. For the 24-week treatment period (Dupixent n=80, placebo n=78), overall rates of adverse events were 84% for Dupixent 300 mg weekly and 71% for placebo. Adverse events that were more commonly (≥5%) observed with Dupixent every week included injection site reactions (38% Dupixent, 33% placebo), fever (6% Dupixent, 1% placebo), sinusitis (5% Dupixent, 0% placebo), COVID-19 (5% Dupixent, 0% placebo) and hypertension (5% Dupixent, 1% placebo). No imbalance was observed in rates of treatment discontinuation due to adverse events between Dupixent (3%) and placebo (3%) groups prior to week 24.
The trial also found that significantly more patients treated with Dupixent 300 mg every two weeks reduced their esophageal eosinophilic count to the normal range compared to placebo; however, there was not a significant improvement in dysphagia symptoms. Detailed results on the every two week dosing will be presented at an upcoming congress.
Data from the clinical trial program have been submitted to the U.S. Food and Drug Administration (FDA). Global regulatory filings in other countries are also planned in 2022.
In September 2020, the U.S. FDA granted Breakthrough Therapy designation to Dupixent for the treatment of patients 12 years and older with EoE. Dupixent was also granted Orphan Drug designation for the potential treatment of EoE in 2017. The potential use of Dupixent in EoE is currently under clinical development, and the safety and efficacy have not been fully evaluated by any regulatory authority.