Regeneron’s Allergen-Blocking Antibodies Meet Phase 3 Endpoints In Cat and Birch Allergy Trials

Regeneron Pharmaceuticals, Inc. announced positive Phase 3 trial results for its investigational allergen-blocking antibodies in adults with moderate-to-severe cat or birch allergies. Both studies met their primary and key secondary endpoints in allergen-challenge models, with results to be presented at an upcoming medical conference. Findings will also support confirmatory Phase 3 studies. 

“Millions suffer from the debilitating effects of allergies, which can cause severe symptoms in the eyes, nose, skin and even trigger asthma. To try to alleviate this suffering, millions undergo allergy desensitization shots, often several times a week for several years, and often with disappointing results. The purpose of these burdensome allergy shots is to try to build up allergen-blocking antibodies in the body. We wondered whether we could instead manufacture and directly provide allergen-blocking antibodies. These recent Phase 3 allergen challenge trials, together with our earlier Phase 2 trials, provide compelling evidence that our first-in-class approach can have the potential to provide profound allergy relief – rapidly and durably after a single treatment – decreasing ocular, nasal and even asthma measures. We see significant relief at the earliest assessment timepoint, and lasting for over three months, in both our cat and birch allergy programs,” said George D. Yancopoulos, M.D., Ph.D., Board co-Chair, President and Chief Scientific Officer at Regeneron, and a co-inventor of this new approach to allergy. 

In the cat allergy ocular challenge trial, patients were randomized to receive either placebo (n=31) or a single subcutaneous dose of REGN1908 and REGN1909, two fully human monoclonal antibodies that block FelD1, the dominant cat allergen. FelD1 exposure often results in ocular, nasal, and respiratory symptoms in more than 20 million patients in the U.S., many of whom do not achieve sufficient relief with standard therapies. Trial results demonstrated clinically meaningful improvements in ocular allergy symptoms after allergen instillation. 

In the birch allergy ocular challenge trial, participants received either a placebo (n=27) or a single dose of REGN5713 and REGN5715, two antibodies designed to block BetV1, the major birch pollen protein responsible for allergic reactions. Birch pollen affects more than 10 million people in the U.S., and around 35% of patients continue to experience symptoms despite standard of care. Results showed that the investigational antibody therapy significantly improved ocular outcomes compared with placebo.