IntroductionSeglor®capsules, a unique modified-release formulation of dihydroergotamine mesilate, have long been in clinical use in France for migraine prophylaxis. The aim of the PROMISE (PROphylaxis of MIgraine with SEglor®) study was to establish the efficacy and tolerability of Seglor®in the prevention of migraine in a general practice setting.MethodsThe PROMISE study was a double blind, placebo-controlled, parallel-group study carried out in primary care practice. It included 363 migraine patients treated with Seglor®or placebo for 5 months after a 1-month placebo run-in phase.ResultsMigraine attack frequency (primary efficacy criterion) decreased markedly in the two treatment groups so that the difference in favour of Seglor®did not reach statistical significance. However, most secondary outcome measures (duration of single attack, total duration of attacks over 1 month, consumption of mild opiate analgesics, subjective improvement) improved to a significantly greater degree in patients receiving Seglor®than in those receiving placebo. In the 84.5% of patients who had impaired quality of life at entry, the percentage of reduction in attack frequency and most other efficacy measures showed significant improvement with Seglor®. The safety profile for Seglor®was comparable to that of placebo.ConclusionThese results support the effectiveness of Seglor®in patients with migraine-related quality-of-life impairment. The findings of the PROMISE study also suggest that patients’ quality of life should be assessed systematically before initiating a preventive treatment for migraine.