Evaluation of the onset and duration of effect of azelastine eye drops (0.05%) versus placebo in patients with allergic conjunctivitis using an allergen challenge model

Objective: The trial evaluated the effectiveness of the investigational ant ihistaminic and antiallergic compound Azelastine Eye Drops (AZE) in the tre atment of allergic conjunctivitis using an allergen challenge model. Design: Randomized, double-blind, placebo-controlled, paired-eye study. Participants: Adults with a history of allergic conjunctivitis (greater tha n or equal to2 years) who were asymptomatic throughout the trial, had a pos itive skin test (cat dander, grass, or ragweed pollen within the last year) , and had a positive conjunctival reaction (score 2+ or more for itching an d redness in both eyes on a 0-4 scale) during two separate conjunctival pro vocation tests (CPT) before randomization. Methods: Eighty patients underwent a 2-week screening period (visits 1 and 2) that included a CPT during visit I to establish the allergen threshold d ose and a second confirmatory GPT performed at visit 2. Eye symptom assessm ents for itching (evaluated by patient) and conjunctiva[ redness (evaluated by physician) were performed 5 and 10 minutes after CPT using a 5-point sc ale (from 0 = none to 4+ = severe). Qualified patients were randomized to r eceive one drop of AZE (0.015 mg of azelastine hydrochloride) in one eye an d one drop of placebo in the other eye 20 minutes before CPT at visit 3 (on set) and 8 or 10 hours before CPT at visit 4 (duration). Main Outcome Measures: Individual severity scores for itching (evaluated by patient) and conjunctival redness (evaluated by physician) for each eye at 3, 5, and 10 minutes after CPT at visits 3 and 4 using a 5-point scale (0 = none to 4+ = Very severe). Results: Each of the 80 randomized patients completed the trial. Mean itchi ng and conjunctival redness scores at visit 3 (onset) were significantly to wer (P < 0.001) in the AZE-treated eyes than in the placebo-treated eyes. A t visit 4 (duration), mean itching and conjunctival redness scores (P <less than or equal to> 0.003) for the 8-hour group and mean itching scores (P l ess than or equal to 0.001) for the In-hour group were significantly lower in the AZE-treated eyes than in the placebo-treated eyes. Significant diffe rences in mean tearing and chemosis severity scores were also seen at visit 3 (onset) and visit 4 (duration) in the AZE-treated eyes when compared wit h the placebo-treated eyes. Treatment with AZE was well tolerated. Conclusions Therapy of experimentally induced allergic conjunctivitis with AZE was highly effective, with an onset of action seen within 3 minutes and a duration of effect of at least 8 to 1 0 hours. (C) 2000 by the American Academy of Ophthalmology.