A multicenter, open-label long-term safety study of rimegepant for the acute treatment of migraine

Background The present study evaluated the long-term safety and tolerability of rimegepant, an orally administered small molecule calcitonin gene-related peptide receptor antagonist, in people with migraine. Methods This multicenter, long-term, open-label safety study included adults (≥18 years) with ≥1 year history of migraine who were sequentially enrolled into three groups: participants in the first two groups had either 2–8 or 9–14 moderate to severe migraine attacks per month by history and treated as needed ( pro re nata [PRN]) with one rimegepant 75 mg oral tablet up to once per calendar day for 52 weeks (PRN 2–8 and PRN 9–14); a third group, included to collect safety data during higher-frequency dosing, had 4–14 moderate to severe migraine attacks per month by history and who took one rimegepant tablet every other day as scheduled dosing plus PRN dosing of one rimegepant tablet for migraine attacks of any severity on nonscheduled dosing days for 12 weeks (every other day (EOD) + PRN). Results Overall, 1800 participants self-administered rimegepant (PRN 2–8: n = 1033; PRN 9–14: n = 481; EOD + PRN: n = 286). The most common on-treatment adverse events (AEs) were upper respiratory tract infection (8.8%), nasopharyngitis (6.8%) and sinusitis (5.1%). Most AEs were mild or moderate and considered unrelated to rimegepant. Serious AEs considered possibly (n = 1) or unlikely (n = 9) related to rimegepant were reported in ten (0.6%) participants. No signal of drug-induced liver injury because of rimegepant was identified. Conclusions Rimegepant 75 mg up to once per day as EOD + PRN for 12 weeks or PRN for up to 52 weeks was safe and well tolerated. No signal of hepatotoxicity, potential drug abuse, or medication-overuse headache was identified. Trial registration: Clinicaltrials.gov: NCT03266588.