Andrews CP, et al. - Researchers undertook this phase 2, double-blind, parallel-group study, to determine if GSP301 [an investigational fixed-dose combination nasal spray of olopatadine hydrochloride (antihistamine) and mometasone furoate (corticosteroid)] affords a safe and effective option for treating patients with seasonal allergic rhinitis (SAR). The randomization process involved 1,111 patients (≥ 12 years of age) with SAR. These patients were equally randomized to twice-daily GSP301 (olopatadine 665μg and mometasone 25μg), once-daily GSP301 (olopatadine 665μg and mometasone 50μg), twice-daily or once-daily olopatadine monotherapy (665μg), mometasone monotherapy (twice-daily 25μg or once-daily 50μg), or placebo for 14 days. They used ANCOVA to assess mean alteration from baseline in morning and evening reflective Total Nasal Symptom Score (rTNSS) as the primary endpoint. Findings revealed the good tolerability as well as the efficacy of twice-daily GSP301 treatment in this patient population. This treatment regimen resulted in statistically significant and clinically meaningful improvements in rTNSS vs placebo and both monotherapies.