Reversion from chronic to episodic migraine in patients with inadequate response to 2-4 classes of migraine preventive treatments in the focus phase 3b study

Abstract

Reversion rates from chronic migraine (CM) to episodic migraine (EM) and changes in monthly number of migraine days were evaluated in this post-hoc analysis of the FOCUS phase 3b study of fremanezumab for migraine prevention. Following IRB approval, CM patients were randomised (1:1:1) to quarterly fremanezumab (month1: 675mg; months 2/3: placebo), monthly fremanezumab (month1: 675mg; months 2/3: 225mg), or matched monthly placebo for 12 weeks of double-blind treatment. Reversion rates were defined as: A) ≥15 headache days (HDs) at baseline but <15 HDs at all 3 months or B) ≥15 HDs at baseline but <15 HDs on average over 12 weeks. At baseline, 167, 167, and 172 patients had CM in the placebo, quarterly fremanezumab, and monthly fremanezumab groups, respectively. Using definition A, 18(11%) with placebo, 59(35%) with quarterly fremanezumab, and 59(34%) with monthly fremanezumab patients reverted to EM. Using definition B, 50(30%), 81(49%) and 91(53%) patients, respectively, reverted. Among reverters, mean changes from baseline in monthly migraine days with placebo, quarterly fremanezumab, and monthly fremanezumab, respectively, were –5.6, –8.2, and –8.4 at 4 weeks and –5.6, –7.8, and –8.6 at 12 weeks for definition A, and –4.7, –7.4, and –7.2 at 4 weeks and –5.3, –7.0, and –7.6 at 12 weeks for definition B. Regardless of definition, higher proportions of CM patients with an inadequate response to 2–4 classes of migraine preventive treatments reverted to EM with fremanezumab versus placebo. Among reverters, clinically meaningful reductions in monthly migraine days were observed with both fremanezumab dosing regimens.