Biohaven Pharmaceutical announced positive top-line results from both of its two Phase 3 clinical trials of rimegepant, an oral CGRP receptor antagonist for the acute treatment of migraine.

In each trial, rimegepant met the co-primary efficacy endpoints of superiority to placebo, at two hours post-dose, on pain freedom and freedom from the most bothersome symptom. "Even without additional rimegepant dosing, or use of rescue medications, these studies showed an early separation from placebo and a profile of continued improvement over the dosing interval. Overall, efficacy and safety results were consistent across both Phase 3 trials," Biohaven said in a statement. Pain freedom at 2 hours for rimegepant treated subjects in Study BHV3000-301 and BHV3000-302 was 19.2% and 19.6%, respectively, versus 14.2% and 12.0% in the placebo treated groups. The magnitude of the treatment effect over placebo at 2 hours or later ranged from 5% to 19% in Study 301 and 7% to 22% in Study 302. "This continued improvement in pain freedom was observed in subjects who took a single dose of rimegepant without use of rescue medications," the company added. Patients treated with rimegepant also achieved statistically significant benefits, as compared to placebo at 2 hours post-dose, in freedom from the MBS. Freedom from the MBS for rimegepant treated subjects in Study 301 and 302 were 36.6% and 37.6%, respectively, versus 27.7% and 25.2% for placebo.

In addition to efficacy observed on the co-primary registrational endpoints, onset of pain relief was observed early after rimegepant treatment with numerical separation evident between 30-45 minutes post-dosing, Biohaven noted. It says rimegepant was found to be both safe and well-tolerated in the two Phase 3 studies with a safety profile similar to placebo. Biohaven expects to present additional results from the two Phase 3 trials at upcoming scientific meetings throughout 2018. The company adds that its on schedule to submit an bew drug application for rimegepant in 2019.