One-year prospective real-world assessment of effectiveness and safety of erenumab in migraine prevention: results of the French FHU INOVPAIN registry study

BACKGROUND: Randomized clinical trials have demonstrated efficacy and safety of erenumab. The aim of this study is to evaluate the effectiveness and safety of erenumab in a real-world setting in French patients with migraine associated with extreme unmet needs. METHODS: This is a one year-prospective real-word study with enrolment of all consecutive adult patients included in the FHU InovPain registry who participated in a compassionate erenumab use program. RESULTS: Of 144 patients included, 140 patients (82.1% female / mean age of 50.9 ± 11.4) received at least one dose of erenumab and were concerned by effectiveness and safety assessment. All patients had failed 11 oral preventive treatments. Most of them suffered from chronic migraine (88.6%) and presented a medication overuse (90.7%) at baseline. Thirty-eight (27.1%) discontinued treatment during the 12-month follow-up, with 22 (15.7%), 11 (7.9%) and 5 (3.6%) patients before 3, 6 or 9 months of treatment. The proportion of ≥ 50% responders at M3, M6, M9 and M12 was 74/140 (52.9%), 69/118 (58.5%), 61/107 (57.0%) and 60/102 (58.8%) respectively. At M3, the rate of reversion from chronic migraine to episodic migraine was 57.3% and the rate of transition from medication overuse to non-overuse was 46.5%. For monthly migraine days, the median (IQR) was 18.0 (13.0–26.0), 9.0 (5.0–17.0), 7.5 (5.0–14.0), 8.0 (5.0–12.5) and 8.0 (5.0–12.0) at M0, M3, M6, M9 and M12 respectively. For HIT-6 score, the median (IQR) was 68.0 (63.8–73.3), 60.0 (54.0–65.0), 60.0 (50.3–53.0), 59.0 (50.0–63.0) and 58.0 (50.0–62.9) at M0, M3, M6, M9 and M12 respectively. Fifty-three (37.9%) patients reported at least one of the following adverse events: cutaneous erythema and/or pain at the injection site for 42 (30%) patients, constipation for 22 (15.7%) patients, muscle spasm for 2 (1.4%) patients, alopecia for one (0.7%) patient and blood pressure increase in one (0.7%) patient. There was no serious adverse event. One female patient became pregnant after 5 months of exposure to erenumab with a safe evolution after treatment discontinuation. CONCLUSION: This first French real-world study related to migraine prevention with CGRP-mAbs confirms effectiveness and safety of erenumab in patients with extreme unmet needs.