Ashina M, et al. – The long–term safety and efficacy of anti–calcitonin gene–related peptide receptor erenumab were evaluated in patients with episodic migraine (EM). The physicians revealed that 1-year efficacy was supported by functional improvements and favorable safety and tolerability profiles. The results necessitated further investigation of erenumab as a preventive treatment in the study group.

• The physicians enrolled patients in a 12-week, double-blind, placebo-controlled clinical trial who continued in an open-label extension (OLE) study will receive erenumab 70 mg every 4 weeks for up to 5 years.
• They conducted this pre-planned interim analysis after all participants had completed the 1-year open-label follow-up, evaluated changes in monthly migraine days (MMD), achievement of ≥50%, ≥75%, and 100% reductions, Headache Impact Test (HIT-6) score, Migraine-Specific Quality of Life (MSQ), Migraine Disability Assessment (MIDAS), and safety.
• Data reported as observed without imputation for missing data.

• The physicians enrolled 472 patients in the parent study.
• Out of them, 383 continued in the OLE with a median exposure to erenumab of 575 days (range 28–822 days).
• At parent study baseline, mean (SD) MMD were 8.8 (2.6), 6.3 (4.2) at week 12 (beginning of OLE), and 3.7 (4.0) at week 64 (mean change from baseline [reduction] of 5.0 days).
• 65%, 42%, and 26% achieved ≥50%, ≥75%, and 100% reduction in MMD, respectively, at week 64.
• At baseline, mean HIT-6 scores were 60.2 (6.3) and 51.7 (9.2) at week 64.
• From baseline through week 64, MSQ and MIDAS improvements were maintained.
• During the OLE, safety profiles were similar to those in the double-blind phase, which overall were similar to placebo.