Naratriptan efficacy in migraineurs who respond poorly to oral sumatriptan

OBJECTIVES: To determine whether 347 patients would respond to a 50-mg oral dose of sumatriptan, even though they considered themselves poor responders to this acute therapy for migraine, and to investigate whether oral naratriptan can be an effective acute therapy for migraine in the subset of patients who did not respond to sumatriptan under double-blind, well-controlled conditions. BACKGROUND: Although most migraineurs respond to sumatriptan, there remains a need for an effective alternative for those who do not respond. Naratriptan is a more potent and more lipophilic member of this class of agent and could prove beneficial in such patients. This is the first well-controlled study to assess the value of another 5-HT1B/1D agonist in this difficult patient subset. METHODS: This study comprised two migraine attacks. The first (attack 1) was a single-blind assessment of the efficacy of sumatriptan (50 mg orally) in patients with a history of poor response to the drug. The second (attack 2) was a randomized, parallel group, double-blind, placebo-controlled trial of naratriptan (2.5 mg orally) in nonresponders to oral sumatriptan. RESULTS: Attack 1: About two thirds of this selected migraine population did not respond to sumatriptan. Attack 2: Naratriptan was statistically superior to placebo for headache relief at 2 hours and 4 hours, as well as for most other features of migraine attacks. These data suggest an intrinsic efficacy of naratriptan in this patient subset and not a coincidental response. No unexpected tolerability issues arose. CONCLUSIONS: Naratriptan is an alternative therapy for migraineurs who respond poorly to oral sumatriptan. No response to one "triptan" does not necessarily predict no response to them all.