A DOSE-RANGING STUDY OF THE EFFICACY AND SAFETY OF AZELASTINE NASAL SPRAY IN THE TREATMENT OF SEASONAL ALLERGIC RHINITIS WITH AN ACUTE MODEL

Background: Oral azelastine, a nonsteroidal antiinflammatory respirato ry investigational drug has demonstrated activity in the treatment of allergic rhinitis and asthma with a good safety profile. Methods: Azel astine nasal spray was compared with sustained-release oral chlorpheni ramine maleate and placebo for efficacy and safety in the treatment of seasonal allergic rhinitis in a double-dummy, two-center a-day, doubl e-blind, randomized, dose-ranging, parallell-groups, onset and duratio n of action study. Two hundred sixty-forty subjects reported to an out door park on Saturday morning during the height of the fall pollen sea son and remained there for 8 hours that day and the next to ensure max imal exposure to seasonal aeroallergens. Symptom diary cards were coll ected hourly Saturday from 8:00 AM to 10:00 AM (baseline period). Subj ects who had sufficient symptoms were randomized into five groups and received medication at 10.00 AM and 10:00 PM on Saturday and at 10:00 AM on Sunday: azelastine 0.1% (1 spray [0.12 mg] per nostril every 12 hours, 2 sprays per nostril every 12 hours, or 2 sprays per nostril on ce daily), Chlor-Trimeton Repetabs (12 mg twice daily), or placebo (tw ice daily). Diary cards were completed hourly (11:00 AM to 4:00 PM) an d at 6:00, 8:00, and 1O:00 PM on Saturday and again hourly on Sunday ( from 8:00 AM to 4:00 PM) to evaluate rhinitis symptoms and adverse eve nts. Results: Two hundred fifty-nine subjects completed the study The groups that received 2 sprays of azelastine per nostril once and twice daily and the chlorpheniramine group had statistically significantly more improvement in total rhinitis symptoms than the placebo group wit hout serious adverse events. Conclusions: This study supports a once t o twice daily dosing regimen for 2 sprays of 0.1% azelastine in the ac ute treatment of allergic rhinitis with onset of action within 2 to 3 hours.