Overview on effectiveness of erenumab, fremanezumab, and galcanezumab in reducing medication overuse headache in chronic migraine patients

Background Migraine is a disabling primary headache disorder with socioeconomic burden. Medication overuse headache (MOH) is caused by chronic overuse of symptomatic drugs often observed in migraine patients. The approved for migraine prevention CGRP antagonists erenumab, fremanezumab, and galcanezumab are effective in migraine prophylaxis but there are only few data regarding efficacy on MOH. Aim of the study To assess efficacy of erenumab, galcanezumab, and fremanezumab in reducing headache in patients with chronic migraine complicated by medication overuse headache. Methods Patients fitting International Classification of Headache Disorders 3rd Edition criteria for chronic migraine and MOH were enrolled and treated with CGRP antagonists without performing drug withdrawal. Efficacy was assessed by improvement of Migraine Impact and Disability Assessment Scale (MIDAS) and reduction of monthly use of symptomatic medications. Patients reporting a ≥ 50% reduction of monthly headache days and ≥ 50% reduction of analgesic and/or triptan use compared with a 3-month baseline period were defined as responders. Results Three hundred three patients, 252 females and 51 males, were enrolled. Patients were treated for at least 6 months up to 1 year. Two hundred forty-two out of 303 (80%) showed both a ≥ 50% reduction of monthly headache days and analgesics intake at 3-month follow-up visit compared to the 3-month baseline period; 239 on 303 (78.8%) continued to have ≥ 50% improvement in both at 6-month follow-up visit. Conclusion Monoclonal antibodies inhibiting CGRP are effective in reducing monthly headache days in migraine patients with MOH.