Flunarizine Versus Topiramate for Chronic Migraine Prophylaxis

Chronic migraine (CM) is a prevalent and devastating disorder with limited therapeutic options. This study explored the efficacy of 10 mg/day flunarizine for CM prophylaxis as compared with 50 mg/day topiramate. We conducted a prospective, randomized, open-label, blinded-endpoint (PROBE) trial. Patients with CM were randomized (1:1) to flunarizine and topiramate treatment groups. This study consisted of two periods: a prospective baseline screening period lasting up to 2 weeks (week -2 to week 0, T0), and a treatment period lasting 8 weeks after enrollment (weeks 0-8, T1-T4). The treatment phase consisted of a 2-week titration period (T1) and a 6-week maintenance period (T2-T4). During the titration period, subjects were given 25 mg/day topiramate or 5 mg/day flunarizine once daily in the first week, followed by 50 mg/day topiramate or 10 mg/day flunarizine in divided doses (twice daily) in the second week. When subjects could not tolerate this target dose, the initial dose was continued through T4. Patients were followed per 2 weeks at the Headache Clinic. At each visit, diaries were collected and directed to the outcome evaluators, who were blinded to the patients' treatment. The primary outcomes assessed were the reductions in the total numbers of headache days and migraine days after 8 weeks of treatment (weeks 7 to 8 vs. weeks -2 to 0). Secondary outcomes were reductions in the numbers of days of acute abortive medication intake and acute abortive medication tablets taken, and the 50% responder rate.