Reuter U, et al. - In patients with episodic migraine in whom previous treatment with two-to-four migraine preventives had been unsuccessful, experts evaluated the effectiveness and tolerability of erenumab (a novel CGRP-receptor antibody). Erenumab was seen to be efficacious in these patients, with a safety profile comparable to placebo. In patients with difficult-to-treat migraine and few treatment options, erenumab may be an option.

Methods

• Researchers conducted a 12-week, double-blind, placebo-controlled randomized study (LIBERTY) at 59 sites in 16 countries.
• Patients who were eligible were 18–65 years of age and had a history of episodic migraine with or without aura for at least 12 months, had migraine for an average of 4–14 days per month during the 3 months before screening, and had been treated unsuccessfully (in terms of either efficacy or tolerability, or both) with between two and four preventive treatments.
• They randomly assigned (1:1) the eligible participants to receive either erenumab 140 mg (via two 70 mg injections) or placebo every 4 weeks subcutaneously for 12 weeks.
• Randomization was by interactive response technology and stratified by monthly frequency of migraine headache (4–7 vs 8–14 migraine days per month) during the baseline phase.
• The randomization list was generated by Cenduit and it also assigned participants to groups.
• They masked the participants, investigators, people doing various assessments, and the study sponsor to treatment assignment.
• The proportion of patients achieving a 50% or greater reduction in the mean number of monthly migraine days during weeks 9–12 was the primary endpoint.
• They measured the efficacy in the full analysis set, which included all randomly assigned patients who started their assigned treatment and completed at least one post-baseline monthly migraine day measurement.
• They assessed the safety and tolerability by recording adverse events and by physical examination, assessment of vital signs, clinical laboratory assessments, and electrocardiography.
• Authors evaluated safety in all randomly assigned patients who received at least one dose of study drug.

Results

• As per data, 246 participants were randomly assigned between March 20, 2017 and October 27, 2017, 121 to the erenumab group and 125 to the placebo group.
• Findings suggested that 95 of 246 (39%) participants had previously unsuccessfully tried two preventive drugs, 93 (38%) had tried three, and 56 (23%) had tried four.
• At week 12, a 50% or greater reduction from baseline in the mean number of monthly migraine days was seen in 36 (30%) patients in the erenumab compared with 17 (14%) in the placebo group (odds ratio 2.7 [95% CI 1.4–5.2]; p=0.002).
• They noted similarity in the tolerability and safety profiles of erenumab and placebo.
• Injection site pain was the most frequent treatment-emergent adverse event, which occurred in seven (6%) participants in both groups.