Efficacy and safety of GSP301 nasal spray in children aged 6 to 11 years with seasonal allergic rhinitis

Background: GSP301 nasal spray is a fixed-dose combination of the antihistamine olopatadine hydrochloride and the corticosteroid mometasone furoate.

Objective: To evaluate the efficacy, safety, and tolerability of GSP301 in pediatric patients (aged ≥6 to <12 years) with seasonal allergic rhinitis (SAR).

Methods: This double-blind, randomized, parallel-group study randomized 446 eligible patients 1:1 (GSP301 [olopatadine hydrochloride 665 μg and mometasone furoate 25 μg] or placebo) as 1 spray/each nostril twice daily for 14 days. The primary end point was change from baseline in average morning and evening subject-reported 12-hour reflective Total Nasal Symptom Score (rTNSS) over a 14-day treatment period analyzed using mixed-effect model repeated measures. Additional assessments included instantaneous Total Nasal Symptom Score, Pediatric Rhinoconjunctivitis Quality of Life Questionnaire, reflective Total Ocular Symptoms Score, instantaneous Total Ocular Symptoms Score, individual symptoms, Physician-assessed Nasal Symptom Score, and adverse events.

Results: GSP301 showed clinically meaningful and statistically significant improvement in rTNSS vs placebo (-0.6; 95% confidence interval, -0.9 to -0.2; P = .001). Statistically significant improvements favoring GSP301 were shown for all individual rTNSS symptoms, instantaneous Total Nasal Symptom Score, and most of its individual symptoms, Physician-assessed Nasal Symptom Score (P = .01), and Pediatric Rhinoconjunctivitis Quality of Life Questionnaire (P < .001). For ocular symptoms, numerical improvements favoring GSP301 were observed, with statistical significance achieved only for reflective "tearing/watering eyes" (P = .04). Treatment-emergent adverse events occurred in 12.0% and 10.4% of patients in the GSP301 and placebo groups, respectively. One subject (0.5%) (placebo group) experienced a serious adverse event (suspected viral meningitis) that was not related to the study treatment and was resolved.

Conclusion: GSP301 was well tolerated and efficacious for treating SAR symptoms in pediatric patients and showed a favorable safety profile.

Trial registration: ClinicalTrials.gov Identifier: NCT03463031.