Purpose: In two 24-week migraine prevention studies in Japan, erenumab was associated with significantly greater reductions in migraine frequency versus placebo over Weeks 13-24 (primary endpoint). This post hoc analysis evaluated the onset of efficacy within the first 4 weeks after the initiation of erenumab from the 24-week double-blind periods of these studies.
Methods: Placebo-adjusted differences in least squares mean (LSM) change from baseline in weekly migraine days (WMD) were assessed weekly in each study and by migraine type (episodic (EM]/chronic [CM]) (Study 20170609).
Results: A total of 407 patients from Study 20120309 (70 mg: N = 135; 140 mg: N = 136; placebo: N = 136) and 261 patients from Study 20170609 ([EM] 70 mg: N = 78; placebo: N = 81; [CM] 70 mg: N = 52; placebo: N = 50) were included. For Study 20120309, onset of efficacy was observed as early as Week 1 in favor of erenumab versus placebo. Placebo-adjusted differences in LSM (95% confidence interval [CI]) change from baseline in WMD at Week 1 were -0.38 (-0.71 to -0.05; p = .022) and -0.49 (-0.82 to -0.16; p = .004) in favor of erenumab 70 and 140 mg, respectively. For Study 20170609, significant placebo-adjusted differences were observed with erenumab 70 mg at Week 1 in patients with EM (LSM [95% CI]: -0.55 [-0.97 to -0.12; p = .012]), and at Week 2 in patients with CM (LSM [95% CI]: -0.81 [-1.53 to -0.09; p = .028]) and for the overall population (LSM [95% CI]: -0.71 [-1.09 to -0.33; p < .001]).
Conclusions: Erenumab treatment significantly reduced WMD compared with placebo. Onset of erenumab efficacy occurred as early as Week 1 in patients with migraine.
Keywords: calcitonin gene-related peptide; chronic migraine; episodic migraine; erenumab; onset of efficacy.
© 2022 The Authors. Brain and Behavior published by Wiley Periodicals LLC.