Efficacy and safety of azelastine 0.15% nasal spray and azelastine 0.10% nasal spray in patients with seasonal allergic rhinitis

Azelastine is a second-generation antihistamine approved for treatment of allergic rhinitis. This randomized, double-blind, placebo- and active-controlled, parallel-group clinical trial evaluated the efficacy and safety of azelastine 0.15% and azelastine 0.10% nasal spray at a dosage of 2 sprays/nostril twice daily in patients with moderate-to-severe seasonal allergic rhinitis (SAR). In total, 526 patients were randomized 1:1:1 to treatment with 2 sprays/nostril twice daily of azelastine 0.15%, azelastine 0.10%, or placebo. The primary efficacy variable was change from baseline in 12-hour reflective Total Nasal Symptom Score (TNSS; A.M. and P.M. combined), consisting of nasal congestion, rhinorrhea, itchy nose, and sneezing. After 2 weeks, the mean improvement and percentage improvement in the 12-hour reflective TNSS were significant (p < 0.001) with azelastine 0.15% and azelastine 0.10% compared with placebo. In a retrospective analysis, there was a statistical difference (p = 0.047) in the mean improvement versus placebo in the 12-hour reflective TNSS with azelastine 0.15% compared with azelastine 0.10%. Onset of action with azelastine 0.15% was within 30 minutes. Bitter taste was the most common adverse event with both azelastine 0.15% and azelastine 0.10% (8.4% and 9.4% of patients, respectively). Somnolence was reported by 1.7% of patients treated with azelastine 0.15%, 0.6% of patients treated with azelastine 0.10%, and 0.6% of patients treated with placebo. Azelastine 0.15% nasal spray at 2 sprays/nostril twice daily significantly improved the nasal symptoms associated with SAR with an onset of action within 30 minutes and was well tolerated.