Acute Efficacy Of Telcagapant In Migraine Patients With Prior Use Of Opioids

Opioids are commonly used for acute migraine treatment despite evidence suggesting that they may increase the risk of migraine chronification. Limited evidence also suggests that prior use of opioids by migraine patients may reduce responsiveness to subsequent acute migraine therapies including triptans. Telcagepant is a novel investigational oral CGRP receptor antagonist with acute antimigraine efficacy comparable to oral triptans. We performed a post-hoc analysis of data from a randomized double-blind placebo-controlled trial to explore whether the efficacy of telcagepant appeared to be influenced by patient's prior use of, and response to, opioids. Patients completed a migraine history questionnaire which asked a) what percentage of their moderate or severe migraine headaches responded to opioid treatment (“75-100%”, “50-74%”, “25-49%”, “less than 25%”, “do not know”, “do not use opioids”, and b) whether they had ever previously used opioids to treat a migraine headache. Four subgroups were defined: SG1) response in ≥75% of opioid-treated attacks, SG2) response in <75% of opioid-treated attacks, SG3) no use - opioid naïve, SG4) no use – opioid experienced. The percentages of patients with 2-hour pain-freedom were: telcagepant 140-mg, SG1 = 9/42 (21.4%), SG2 = 16/80 (20.0%), SG3 = 91/393 (23.2%), SG4 = 5/28 (17.9%); telcagepant 280-mg, SG1 = 9/36 (25.0%), SG2 = 20/89 (22.5%), SG3 = 100/378 (26.5%), SG4 = 1/14 (7.1%). The percentages with 2-hour pain-relief (reduction to mild or none) were: telcagepant 140-mg, SG1 = 27/42 (64.3%), SG2 = 43/80 (53.8%), SG3 = 234/393 (59.5%), SG4 = 19/28 (67.9%); telcagepant 280-mg, SG1 = 25/36 (69.4%), SG2 = 49/89 (55.1%), SG3 = 213/378 (56.3%), SG4 = 8/14 (57.1%). These findings suggest that the efficacy of telcagepant is generally similar regardless of whether patients previously used, or responded to, opioids. The findings require confirmation in prospective studies. (Study funded by Merck Research Laboratories.)