Methods: A multicenter, randomized, double-blind, double-dummy, parallel-group study in SAR patients was conducted. After 1-week placebo run-in period, patients were randomized to ONO-4053, leukotriene receptor antagonist, or placebo for 2-week treatment period. Nasal and ocular symptoms were assessed every day with electronic patient-reported outcome throughout the study period by the patients.
Results: Two hundred patients were enrolled in the study and 195 patients were included in FAS. Both ONO-4053 and LTRA were more effective than placebo in all nasal and ocular symptoms. ONO-4053 was more effective than LTRA in TNSS, sneezing, rhinorrhea, and nasal itching. The differences of the LSMeans between ONO-4053 and placebo and between LTRA and placebo were -0.47 and -0.21 in TNSS, -0.17 and -0.06 in sneezing, -0.16 and -0.08 in rhinorrhea, and-0.12 and -0.06 in nasal itching, respectively. The effect of ONO-4053 on nasal obstruction was equal to or greater than that of LTRA (-0.07 and -0.06). ONO-4053 reduced the symptoms of sneezing, rhinorrhea, and nasal itching more rapidly than LTRA. There were no safety concerns.
Conclusions: ONO-4053 was as safe as and more effective than LTRA. ONO-4053 seems useful for treating SAR. We think ONO-4053’s mechanism of reducing histamine-related symptoms like sneezing is not only the reaction of DP1 antagonism but also the reaction to block releasing chemical mediators like histamines from mast cells.