Fremanezumab for Episodic Migraine Prevention in Japanese Patients: Subgroup Analysis from Two International Trials

Purpose: The monoclonal antibody fremanezumab has been shown effective and well tolerated in numerous Phase 2 and Phase 3 trials. This subgroup analysis of the international HALO episodic migraine (EM; [NCT02629861]) trial and a similarly designed phase 2b/3 trial in Japanese and Korean patients (NCT03303092) sought to evaluate the efficacy and safety of fremanezumab in Japanese patients with EM. Patients and Methods: In both trials, eligible patients were randomly assigned at baseline to receive subcutaneous monthly fremanezumab, quarterly fremanezumab, or placebo in a 1:1:1 ratio. The primary endpoint was the mean change from baseline in the monthly (28-day) average number of migraine days during the 12-week period after the first dose of fremanezumab or placebo. Secondary endpoints assessed other aspects of efficacy, including disability and medication use. Results: A total of 301 patients in the Japanese and Korean phase 2b/3 trial and 75 patients in the HALO EM trial were Japanese with baseline and treatment characteristics similar between treatment groups. According to ANCOVA analysis of the primary endpoint, both fremanezumab quarterly and monthly led to greater reductions in the monthly (28-day) average number of migraine days than placebo. This was supported by MMRM analysis of the primary endpoint over the initial 4 weeks, highlighting the rapid onset of action of fremanezumab. Results of secondary endpoint analysis supported the primary endpoint analyses. Fremanezumab was well tolerated with no new safety signals seen in this population of Japanese patients. Conclusion: Fremanezumab appears to be an effective and well-tolerated preventive medication for Japanese patients with EM.