Regeneron Unveils First-in-Class Phase 3 Data for Novel Cat and Birch Allergy Treatments at AAAAI 2026
Key Insights
Regeneron presents first-time Phase 3 data for two potentially first-in-class allergen-blocking antibody cocktails targeting cat and birch allergies, demonstrating significant reduction in ocular symptoms and skin reactivity.
The company will embark on additional registration-enabling trials this year based on promising Phase 3 results from separate allergen-challenge studies evaluating FelD1 (search) and BetV1 targeting therapies.
New Dupixent data across 36 abstracts highlight expanded clinical applications, including late-breaking Phase 3 AIMS trial results for allergic fungal rhinosinusitis (search) currently under FDA Priority Review.
Regeneron Pharmaceuticals announced groundbreaking Phase 3 data for two investigational allergen-blocking antibody treatments targeting cat and birch allergies, marking a potential paradigm shift in allergy treatment. The biotechnology company will present 36 abstracts across its immunology portfolio at the 2026 American Academy of Allergy, Asthma (search) and Immunology (AAAAI) Annual Meeting in Philadelphia from February 27 to March 2.
Novel Allergen-Specific Therapies Show Promise
The Phase 3 allergen-challenge trials evaluated distinct antibody cocktails designed to target the most dominant allergens: FelD1 (search) for cat allergy (search) and BetV1 for birch allergy (search). These separate studies assessed the therapies' ability to reduce ocular allergic symptoms, including ocular itch and conjunctival redness, in response to antigen challenge using the Ora Conjunctival Challenge Model (Ora-CAC). The treatments also demonstrated reduced skin prick reactivity one week after treatment compared to placebo.
"At Regeneron, we are pioneering new approaches to treating allergic diseases, and at AAAAI we will present for the first time Phase 3 data from two potentially first-in-class treatments for cat and birch allergies invented by Regeneron scientists that have the potential to change the paradigm for treatment of allergic diseases," said Boaz Hirshberg, M.D., Senior Vice President, Clinical Development, Internal Medicine at Regeneron.
The results build upon earlier trial data demonstrating the cocktails' effects on nasal, respiratory and skin endpoints in these patient populations. Based on these Phase 3 findings, Regeneron plans to initiate additional registration-enabling trials this year that will evaluate similar endpoints with longer follow-up periods.
Broader Allergy Pipeline Strategy
The cat and birch allergy (search) programs represent components of Regeneron's comprehensive allergy pipeline, which includes innovative strategies aimed at eliminating all IgE-mediated allergies. The safety and efficacy of these investigational medicines have not yet been evaluated by regulatory authorities.
Among the key presentations will be abstract 746, "A Single Prophylactic Dose of REGN1908-1909 Significantly Suppressed Cat-Allergen Induced Allergic Conjunctivitis Signs and Symptoms and Skin Test Reactivity," and abstract 742, "Antibody Cocktail Targeting Bet v1 Reduces Signs and Symptoms of Allergic Conjunctivitis in Birch Allergic Individuals Undergoing Conjunctival Allergen Challenge."
Dupixent Expands Clinical Applications
Regeneron will also present extensive new data on Dupixent (dupilumab), developed in collaboration with Sanofi, across dermatological, respiratory and gastrointestinal diseases. Notably, late-breaking data from the Phase 3 AIMS trial in adults and children aged 6 years and older with allergic fungal rhinosinusitis (search) (AFRS) will be presented. These results formed the basis for a supplemental Biologics License Application currently under FDA Priority Review with a target action date of February 28, 2026.
New long-term analyses from a Phase 3 open-label extension trial will examine Dupixent's impact on allergy sensitization in children with moderate-to-severe atopic dermatitis (search). The studies measured IgE levels for common food and environmental allergies, including egg white, peanut, cow's milk, wheat, dust mite, and plant or fungal/bacterial allergens throughout up to 1.5 years of treatment.
Real-World Evidence and Treatment Positioning
Two real-world analyses will evaluate the potential for positioning Dupixent earlier in asthma (search) treatment paradigms. These studies measured reduction of exacerbations and systemic corticosteroid use in patients uncontrolled on medium-dose inhaled corticosteroids, comparing Dupixent addition with escalation to high-dose inhaled corticosteroids or addition of other biologics.
"These results highlight the potential of Dupixent to further evolve the treatment paradigms of several chronic diseases, including asthma (search), certain allergic fungal diseases and allergies in children with atopic dermatitis (search)," Hirshberg noted.
VelocImmune Technology Foundation
The investigational treatments leverage Regeneron's proprietary VelocImmune technology, which utilizes a genetically engineered mouse platform with a humanized immune system to produce optimized fully human antibodies. This technology has been instrumental in creating a substantial proportion of FDA-approved fully human monoclonal antibodies, including Dupixent and several other Regeneron therapeutics.
The comprehensive AAAAI presentation schedule includes studies across multiple therapeutic areas, from basic immunological research to real-world effectiveness data, demonstrating Regeneron's commitment to advancing allergy and immunology treatment options through scientific innovation.