Clinically Relevant Activity of the Novel RASP Inhibitor Reproxalap in Allergic Conjunctivitis: The Phase 3 ALLEVIATE Trial

Abstract

Purpose: To assess the post-acute activity and clinical utility of reproxalap, a novel reactive aldehyde species (RASP) inhibitor, versus vehicle in patients with seasonal allergic conjunctivitis.

Design: Parallel-group, double-masked, randomized Phase 3 trial.

Methods: Two topical ocular reproxalap concentrations (0.25% and 0.5%) were evaluated versus vehicle in patients with allergic conjunctivitis randomized 1:1:1 and treated with test article 10 minutes prior to conjunctival seasonal allergen challenge. The primary endpoint was area under the post-acute ocular itching score (range = 0-4) curve from 10 to 60 minutes after challenge. The key secondary endpoint was the proportion of subjects with ≥2 points improvement from their peak ocular itching score at baseline.

Results: A total of 318 patients were randomized at 11 US sites. Both concentrations of reproxalap (0.25% and 0.5%) achieved the primary endpoint (P < .0001 and P = .003, respectively) and the key secondary endpoint (P = .0005 and P = .02, respectively). Time to complete resolution of ocular itching was statistically faster for both reproxalap concentrations than for vehicle (P < .0001 and P = .001, respectively). No safety or tolerability concerns were noted. The most common adverse event was mild and transient instillation site irritation.

Conclusion: Reproxalap was effective at reducing ocular itching in patients with allergic conjunctivitis. Reproxalap activity was clinically relevant, as assessed by responder-based and distributional analyses. ALLEVIATE represents one of the first allergic conjunctivitis Phase 3 trials of a novel mechanism of action in decades, and is unique among conjunctival allergen challenge trials in assessing clinical relevance with standard and validated techniques.