Both perimenstrual and nonperimenstrual migraine days respond to anti-calcitonin gene-related peptide (receptor) antibodies

Background and purpose: Anti-calcitonin gene-related peptide (CGRP) (receptor) antibodies effectively reduce overall migraine attack frequency, but whether there are differences in effect between perimenstrual and nonperimenstrual migraine days has not been investigated. Methods: We performed a single-arm study among women with migraine. Participants were followed with electronic E-diaries during one (pretreatment) baseline month and 6 months of treatment with either erenumab or fremanezumab. Differences in treatment effect on perimenstrual and nonperimenstrual migraine days were assessed using a mixed effects logistic regression model, with migraine day as dependent variable; treatment, menstrual window, and an interaction term (treatment × menstrual window) as fixed effects; and patient as a random effect. Results: There was no interaction between the menstrual window and treatment effect, indicating that the reduction in migraine days under treatment was similar during the menstrual window and the remainder of the menstrual cycle (odds ratio for treatment = 0.44, 95% confidence interval = 0.38–0.51). Conclusions: Our findings support prophylactic use of anti-CGRP (receptor) antibodies for women with menstrual migraine, as this leads to consistent reductions in number of migraine days during the entire menstrual cycle.