Bioequivalence of rimegepant, a small molecule CGRP receptor antagonist, administered as an oral tablet, a sublingual orally disintegrating tablet, and a supralingual orally disintegrating tablet: two phase 1 randomized studies in healthy adults

Background: Rimegepant is an orally administered small molecule calcitonin gene-related peptide receptor antagonist indicated for the acute and preventive treatment of migraine. Methods: Two single-center, phase 1, open-label, randomized bioequivalence studies were conducted in healthy adult non-smokers, aged 18-55 years. One study compared the rate and extent of absorption of the marketed formulation of rimegepant 75 mg orally disintegrating tablet (ODT) administered sublingually with rimegepant 75 mg oral tablet, an earlier development formulation; the second compared the rate and extent of absorption of 75 mg rimegepant ODT administered supralingually with rimegepant oral tablet. Results: The ln-transformed geometric mean ratios for the area under the curve (AUC) from time 0 to the last available concentration time point (time t) (AUC(0-t)), AUC from time 0 to infinity (AUC(0-inf)), and maximum observed concentration (C-max) of sublingual rimegepant ODT vs. rimegepant tablet were 97, 97, and 105%, respectively, and the 90% confidence intervals (CIs) were all within the predefined range (80-125%) for bioequivalence. The ln-transformed geometric mean ratios for the AUC(0-t) and AUC(0-inf) of supralingual rimegepant ODT vs. rimegepant tablet were 98%, the 90% CIs were within the predefined range (80-125%), and the geometric mean ratio for C-max was 103% with the 95% upper confidence bound for the scaled average bioequivalence criterion of -0.0575 (within-participant coefficient of variation for the reference for C-max > 30%) for bioequivalence. Conclusions: Rimegepant 75 mg ODT, administered sublingually or supralingually, and rimegepant 75 mg oral tablet were bioequivalent.