Efficacy and safety of fevipiprant in patients with uncontrolled asthma: Two replicate, phase 3, randomised, double-blind, placebo-controlled trials (ZEAL-1 and ZEAL-2).

Abstract Background These studies assessed the efficacy and safety of fevipiprant, an oral antagonist of the prostaglandin D2 (PGD2) receptor (DP2), compared with placebo when added to standard-of-care (SoC) asthma therapy in patients with uncontrolled asthma. Methods ZEAL-1 (NCT03215758) and ZEAL-2 (NCT03226392) are two replicate, phase 3, multicentre, randomised, double-blind, placebo-controlled, parallel-group studies in which fevipiprant 150 mg once daily (o.d.) or placebo was added to SoC asthma therapy in patients aged ≥12 years with uncontrolled asthma. Primary endpoint: change from baseline in pre-dose forced expiratory volume in 1 s (FEV1) after 12 weeks’ treatment. Key secondary endpoints: daytime asthma symptom score, short-acting β-agonist (SABA) use and Asthma Quality-of-Life Questionnaire (AQLQ+12) score after 12-weeks treatment. Findings 662 patients in ZEAL-1 and 685 patients in ZEAL-2 completed the treatment period. In ZEAL-1, the least squares (LS) mean change from baseline in pre-dose FEV1 was 112 mL in fevipiprant vs 71 mL in placebo group (difference [∆]:41 mL; 95% CI: −6, 88; adjusted p-value 0·088). In ZEAL-2, the LS mean change in pre-dose FEV1 was 126 mL and 157 mL in the fevipiprant and placebo groups, respectively (∆:−31 mL; 95% CI: −80, 18; adjusted p-value 0·214). For both studies, there were no statistically significant differences in the key secondary objectives between the treatment groups. Interpretation The ZEAL studies did not demonstrate significant improvement in lung function or other clinical outcomes. These results suggest that DP2 receptor inhibition with fevipiprant is not effective in the studied patient population.