May 06, 2010
Telcagepant Efficacy Unaffected by Prior Use of Opioids for Migraine
Results of a post-hoc analysis of data from a randomized, double-blind, placebo-controlled trial suggest the answer is “no,” specifically regarding efficacy of telcagepant, a novel investigational oral calcitonin gene-related peptide receptor antagonist that has acute antimigraine efficacy comparable to oral triptans.
Andrew P. Ho, MD, and colleagues from Merck Research Laboratories, North Wales, Pa., reviewed patient-completed migraine history questionnaires that asked the percentage of moderate or severe migraine headaches that responded to opioid treatment (75-100%, 50-74%, 25-49%, <25%, did not know, or did not use opioids), and whether opioids had ever previously been used to treat a migraine headache.
Based on replies to the questionnaire, four patient subgroups were categorized. Subgroup 1 identified a response in ≥75% of opioid-treated attacks; subgroup 2 had a response in <75% of opioid-treated attacks; subgroup 3 was opioid-naïve, and subgroup 4 had not used opioids to treat a migraine headache but had used opioids previously.
Percentages of patients reporting 2-hour pain freedom for the telcagepant 140 mg dose were 21.4% in subgroup 1 (9/42 patients); 20.0% in subgroup 2 (16/80); 23.2% in subgroup 3 (91/393); and 17.9% in subgroup 4 (5/28). For the telcagepant 280 mg dose, 2-hour pain freedom was 25.0% in subgroup 1 (9/36 patients); 22.5% in subgroup 2 (20/89); 26.5% in subgroup 3 (100/378); and 7.1% in subgroup 4 (1/14).
Those reporting 2-hour pain relief (defined as reduction to mild or none) for the telcagepant 140 mg dose were 64.3% in subgroup 1 (27/42 patients); 53.8% in subgroup 2 (43/80); 59.5% in subgroup 3 (234/393); and 67.9% in subgroup 4 (19/28). For the telcagepant 280 mg dose, 2-hour pain relief was 69.4% in subgroup 1 (25/36 patients); 55.1% in subgroup 2 (49/89); 56.3% in subgroup 3 (213/378); and 57.1% in subgroup 4 (8/14). Please see corresponding PowerPoint slides for more information.
These findings, suggesting that telcagepant efficacy is similar regardless of whether patients used—or previously responded to—opioids, require confirmation in prospective studies, the investigators reported during the American Pain Society's 29th Annual Scientific Meeting.