Segall N, et al. - Researchers performed this randomized, double-blind, parallel-group study to test GSP301 nasal spray—an investigational fixed-dose combination of olopatadine hydrochloride and mometasone furoate— for its long-term (52 weeks) safety and effectiveness in patients with perennial allergic rhinitis (PAR) (n = 601; ages ≥ 12 years). In a randomized 4:1:1 manner, the participants were administered twice-daily GSP301 (olopatadine 665 μg and mometasone 25 μg [pH 3.7]) or two GSP301 vehicle formulations (placebo pH 3.7 or 7.0). For GSP301 vs placebo pH 3.7, they evaluated the shift from baseline in the average A.M. reflective Total Nasal Symptom Score and instantaneous Total Nasal Symptom Score, Physician-assessed Nasal Symptom Scores, and quality of life. Findings revealed good tolerability of twice-daily GSP301, as well as its ability to bring about statistically significant and clinically meaningful improvements in PAR nasal symptoms when compared with placebo over 52 weeks. Additionally, a favorable safety profile and efficacy were displayed by twice-daily GSP301.