These post hoc analyses demonstrated that fremanezumab, compared with placebo, significantly reduced the monthly average number of headache days of at least moderate severity and led to a significantly greater proportion of patients who had a clinically meaningful ≥ 50% response rate, independently of the presence of MO in patients with CM. Similar reductions were also seen for migraine days. In patients with baseline MO, significantly more fremanezumab-treated patients reverted to no MO during the 12-week treatment period compared with those who received placebo. Significant reductions in days using acute headache medication were also observed in patients with and without MO at baseline, with the greatest numerical reductions noted in those who reverted from MO to no MO during the 12-week treatment period.