The primary endpoint of the study, mean change from baseline (28-day pretreatment period) in the monthly average number of headache days of at least moderate severity during the 12-week treatment period, has been previously described [16]. Herein, post hoc analyses were conducted to assess the impact of fremanezumab in patients with and without MO. Patients were grouped based on the presence or absence of baseline MO, which was defined as use of acute headache medication on ≥15 days, migraine-specific acute medication on ≥10 days, or combination medications for headache on ≥10 days during the 28-day pretreatment period [17].