Regeneron at AAAAI 2026: First Phase‑3 Allergen‑Challenge Readouts and Dupixent sBLA

In a February 10, 2026 press release, Regeneron says AAAI 2026 immunology abstracts spanning 36 abstracts across its immunology and inflammation portfolio and pipeline will be presented at the meeting. The release highlights first-time Phase 3 allergen-challenge presentations for two investigational allergen-blocking antibody cocktails, along with new analyses involving Dupixent (dupilumab) and a U.S. supplemental Biologics License Application (sBLA) for AFRS that the release says is under Priority Review with a target action date of February 28, 2026.

The release also describes separate investigational programs for cat and birch allergies, each with Phase 3 allergen-challenge results slated for presentation. According to the company, the cat-allergy program evaluates an antibody cocktail targeting Fel d 1, while the birch-allergy program evaluates an antibody cocktail targeting Bet v 1. The release characterizes these as first-time Phase 3 presentations from two distinct allergen-specific programs, described in an “ocular (conjunctival) allergen challenge” setting.

For these Phase 3 conjunctival allergen-challenge trials, the press release reports that ocular allergic symptoms were assessed in response to antigen challenge, specifically citing ocular itch and conjunctival redness, each described as evaluated versus placebo. The release also states that skin prick reactivity was assessed one week after treatment, again described in comparison with placebo. In this framing, the planned Phase 3 presentations are tied to ocular symptom measures and skin test reactivity versus placebo.

Looking beyond the initial Phase 3 presentations, the release outlines additional next steps for both the cat and birch programs. It states that additional registration-enabling trials for both programs are initiating this year and are expected to evaluate similar endpoints after longer follow-up. The company also notes that the safety and efficacy of these investigational medicines have not been evaluated by any regulatory authority.

The release also lists multiple Dupixent-related analyses planned for AAAAI 2026, including long-term assessments of allergen-specific IgE in children with moderate-to-severe atopic dermatitis, with IgE levels for common food and environmental allergies measured for up to 1.5 years. It also describes two real-world asthma analyses in adults and adolescents that evaluated outcomes after treatment escalation from medium-dose inhaled corticosteroids, comparing addition of Dupixent with escalation to high-dose inhaled corticosteroids or addition of other biologics for uncontrolled asthma. In addition, the release says late-breaking Phase 3 AIMS data in AFRS formed the basis for a U.S. supplemental Biologics License Application currently Dupixent sBLA under Priority Review, with a stated target action date of February 28, 2026. In this way, the meeting preview pairs planned disclosures with an explicitly stated U.S. regulatory timeline.

Key Takeaways:

• The release states that first-time Phase 3 allergen-challenge presentations are planned for investigational antibody cocktails targeting Fel d 1 (cat) and Bet v 1 (birch).
• The release reports conjunctival allergen-challenge readouts focused on ocular symptom assessments and skin test reactivity versus placebo.
• The release describes Dupixent analyses spanning long-term allergen-specific IgE measurement in children with atopic dermatitis, real-world asthma escalation comparisons, and an AFRS sBLA under Priority Review with a stated target action date.