Objective: To assess the efficacy and tolerability of oral almotriptan, a selective serotonin receptor (5-HT1B/1D) agonist, when used at different doses in the treatment of acute migraine.
Methods: This was a placebo controlled, double-blind, parallel-group, dose-finding study. Patients satisfying International Headache Society criteria for acute migraine were randomized to a single dose of placebo or oral almotriptan 2, 6.25, 12.5, or 25 mg at the onset of moderate or severe pain. Patients graded pain intensity on a 4-point verbal scale from 0 (no pain) to 3 (severe pain) and recorded adverse events. The primary efficacy variable was headache response at 2 hours. Data were analyzed on an intent-to-treat basis.
Results: Nine hundred and three patients were randomized, and 742 were included in the evaluation of the efficacy and tolerability. Headache response at 2 hours was 32.5% with placebo, and 30%, 56.3%, 58.5%, and 66.5% with almotriptan 2, 6.25, 12.5, and 25 mg doses (p < 0.05 for 6.25, 12.5, and 25 mg vs placebo). A dose-dependent decrease in the incidence of migraine-associated symptoms and the need for escape medication was observed. The incidence of adverse events with the almotriptan 2-mg, 6.25-mg, and 12.5-mg groups was comparable to that with the placebo group.
Conclusion: Almotriptan 12.5 mg demonstrated the most favorable ratio between efficacy and tolerability, offering equivalent efficacy and better tolerability compared with the 25 mg dose. The minimum effective dose of almotriptan was 6.25 mg.