Background: Azelastine nasal spray is a topical antihistamine with a distinctive taste that may be objectionable to some patients. The primary objectives of this clinical trial were (1) to determine if a reformulated azelastine nasal spray (Astepro) with sucralose as a taste-masking agent provides comparable efficacy to the original formulation (Astelin) and (2) to evaluate dose-response relationships between groups.
Methods: Eight hundred thirty-five patients with seasonal allergic rhinitis were randomized to six treatment groups: (1) original azelastine nasal spray, 1 spray/nostril b.i.d.; (2) reformulated azelastine, 1 spray/nostril b.i.d.; (3) placebo, 1 spray/ nostril b.i.d.; (4) original azelastine nasal spray, 2 sprays/nostril b.i.d., (5) reformulated, 2 sprays/nostril b.i.d.; and (6) placebo, 2 sprays/nostril b.i.d. The primary efficacy variable was the change from baseline to day 14 in total nasal symptom score (TNSS) consisting of runny nose, sneezing, itchy nose, and nasal congestion.
Results: Original azelastine nasal spray and the reformulated spray produced comparable improvements in the TNSS at both dosages. There was a dose-related difference in TNSS comparing the 1- and 2-spray dosages. The percentage changes from baseline in the TNSS in the 2-sprays/nostril dosage groups were 27.9% (p<0.001) with the reformulated nasal spray, 23.5% (p<0.01) with the original formulation, and 15.4% with placebo. The incidence of bitter taste was 7% with the reformulated spray and 8% with the original at the 2-sprays/nostril dosage.
Conclusion: The results of this study showed efficacy both with original azelastine nasal spray and with the reformulated nasal spray and a clear dose-response difference between the 1- and 2-spray dosages.