Background Erenumab was effective and well tolerated in a pivotal clinical trial of chronic migraine. Here, we evaluated efficacy and safety of monthly erenumab (70 mg or 140 mg) versus placebo in the subgroup of patients who had previously failed preventive treatment(s) (≥ 1, ≥ 2 prior failed medication categories) and in patients who had never failed. Methods Subgroup analyses evaluated change from baseline in monthly migraine days; achievement of ≥ 50% and ≥ 75% reduction in monthly migraine days; and change in monthly acute migraine-specific medication days. Adverse events were evaluated for each subgroup. Results Treatment with both doses of erenumab resulted in greater reductions in monthly migraine days (primary endpoint) at Month 3 (treatment difference [95% CI], never failed subgroup: -2.2 [-4.1, -0.3] for 70 mg and -0.5 [-2.4, 1.5] for 140 mg; ≥ 1 prior failed medication categories subgroup: -2.5 [-3.8, -1.2], for 70 mg and -3.3 [-4.6, -2.1] for 140 mg; ≥ 2 prior failed medication categories subgroup: -2.7 [-4.2, -1.2], for 70 mg and -4.3 [-5.8, -2.8] for 140 mg). Similar results were observed in the monthly acute migraine-specific medication days endpoint, and in the achievement of ≥ 50% and ≥ 75% reduction in monthly migraine days. There were no new or unexpected safety issues. Conclusion Erenumab showed consistent efficacy in chronic migraine patients who had failed prior preventive treatments and was well tolerated across subgroups.

Amgen Inc Thousand Oaks CA USA

Danish Headache Center and Department of Neurology Rigshospitalet Glostrup Faculty of Medical and Health Sciences University of Copenhagen Copenhagen Denmark

Department of Neurology Charité Universitätsmedizin Berlin Berlin Germany

Geisel School of Medicine at Dartmouth Hanover NH USA

Headache Unit Neurology Department University Hospital Center of Montreal Montreal QC Canada

Nashville Neuroscience Group and Department of Neurology Vanderbilt University Nashville TN USA

Novartis Pharma AG Basel Switzerland

Prague Headache Center DADO MEDICAL s r o Prague Czech Republic

References provided by Crossref.org

Long-term efficacy and safety of erenumab in patients with chronic migraine in whom prior preventive treatments had failed: A subgroup analysis

Fremanezumab for the Preventive Treatment of Migraine: Subgroup Analysis by Number of Prior Preventive Treatments with Inadequate Response