Oral sumatriptan for the acute treatment of probable migraine: First randomized, controlled study

Objective. - To evaluate the efficacy and tolerability of sumatriptan tablets in adults who meet International Headache Society (IHS) criteria for probable migraine but who do not meet IHS criteria for migraine with or without aura. Background. - Headaches with some but not all of the features of migraine meet criteria for probable migraine, a form of migraine recognized by the IHS. Probable migraine attacks are also prevalent and frequently underdiagnosed. Methods. - This was a randomized, multicenter, double-blind, placebo-controlled, parallel-group study. Adults (18 to 65 years) with a 1-year history of headaches that met 2004 IHS criteria for probable migraine without aura (same operational definition as 1988 IHS migrainous disorder) were eligible for enrollment. All patients were triptan- and ergot-naïve and had never been diagnosed with migraine. Patients were randomized in a 1:1:1:1 fashion to receive sumatriptan 25, 50, or 100 mg conventional tablets or matching placebo and were instructed to treat a single moderate or severe probable migraine attack. A post hoc analysis was conducted to evaluate the population of patients who achieved headache relief sustained throughout the immediate posttreatment period. Patients who reported relief within 2 hours and subsequently lost headache relief within 4 hours were considered nonresponders. Results. - At 2 hours, more patients treated with sumatriptan achieved headache relief, the primary efficacy measure, compared with placebo, but differences only approached statistical significance for 100 mg (P= .053). The 2-hour headache relief rate in the sumatriptan 25 or 50 mg groups was not significantly different than placebo. The time to use of rescue was significantly shorter in the placebo group compared with the sumatriptan 100 mg group (P= .002). The time to use of rescue in the sumatriptan 25 or 50 mg groups was not significantly different than placebo. More patients treated with placebo (22%) lost headache relief within 4 hours compared with patients treated with sumatriptan 25 mg (17%), 50 mg (14%), or 100 mg (7%). A post hoc analysis demonstrated that at 2 hours, headache relief sustained through 4 hours (S 0-4 hours) was achieved in 44%, 49%, and 57% of patients treated with sumatriptan 25, 50, and 100 mg, respectively, compared with 34% of patients treated with placebo (P < .05 for sumatriptan 50 and 100 mg vs. placebo). All doses of sumatriptan were well tolerated and no serious adverse events were reported. Conclusion. - These results suggest that oral sumatriptan may be effective and is well tolerated for the acute treatment of probable migraine without aura, however, the difference between sumatriptan and placebo was not statistically significant for the a priori defined primary endpoint.