Phase 3b randomized controlled trial of fevipiprant in patients with nasal polyposis with asthma (THUNDER)

Background: Chronic rhinosinusitis with nasal polyps (CRSwNP) is associated with asthma, particularly of late onset. Current treatment options for CRSwNP have limitations, and there is an unmet need for other safe and effective therapies. Objective: The aim of the THUNDER study was to determine the efficacy and safety of the prostaglandin D-2 receptor 2 (DP2) antagonist fevipiprant in patients with CRSwNP and concomitant asthma, measured by improvement in nasal polyp score (primary end point), nasal congestion score, Sinonasal Outcome Test 22 score, and University of Pennsylvania Smell Identification Test score. Methods: THUNDER was a phase 3b, randomized, multicenter, double-blind, placebo-controlled, parallel-group, 16-week study of fevipiprant 150 mg or 450 mg once daily versus placebo. All patients received intranasal mometasone furoate 200 mu g daily. Results: Ninety-eight patients were randomly assigned to fevipiprant 150 mg (n = 32), fevipiprant 450 mg (n = 34), or placebo (n = 32). Mean (SE) change from baseline in nasal polyp score at week 16 was 0.20 (0.224) for fevipiprant 150 mg, -0.10 (0.216) for fevipiprant 450 mg, and 0.14 (0.233) for placebo. Mean treatment difference was 0.05 (95% confidence interval, -0.59, 0.70; adjusted P = .979) for fevipiprant 150 mg versus placebo and -0.25 (95% confidence interval, -0.88, 0.39; adjusted P = .656) for fevipiprant 450 mg versus placebo. There was no meaningful difference in the secondary end points for fevipiprant versus placebo. Conclusions: THUNDER provided no evidence of a role for fevipiprant in the treatment of patients with CRSwNP and asthma; future studies may establish a role for other DP2 antagonists, specifically in patients with aspirin-exacerbated respiratory disease.