Reversion from chronic migraine to episodic migraine following treatment with erenumab: Results of a <i>post-hoc</i> analysis of a randomized, 12-week, double-blind study and a 52-week, open-label extension
Richard B. Lipton, Stewart J. Tepper, Stephen D. Silberstein, David Kudrow, Messoud Ashina, Uwe Reuter, David W. Dodick, Feng Zhang, Gregory A. Rippon, Sunfa Cheng, Daniel D. Mikol
Abstract
Objective To determine reversion rates from chronic migraine to episodic migraine during long-term erenumab treatment. Methods A daily headache diary was completed during the 12-week, double-blind treatment phase of a placebo-controlled trial comparing erenumab 70 mg, 140 mg, and placebo, and weeks 1–12, 21–24, 37–40, and 49–52 of the open-label treatment phase. Chronic migraine to episodic migraine reversion rates were assessed over the double-blind treatment phase; persistent reversion to episodic migraine over 24 weeks (double-blind treatment phase through the first 12 weeks in the open-label treatment phase), long-term persistent reversion to episodic migraine over 64 weeks (double-blind treatment phase plus open-label treatment phase); delayed reversion to episodic migraine through the first 12 weeks of the open-label treatment phase among patients remaining in chronic migraine during the double-blind treatment phase. Results In the double-blind treatment phase, 53.1% (95% confidence interval: 47.8–58.3) of 358 erenumab-treated completers had reversion to episodic migraine; monthly reversion rates to episodic migraine were typically higher among patients receiving 140 mg versus 70 mg. Among 181 completers (receiving erenumab for 64 weeks), 98 (54.1% [95% confidence interval: 46.6–61.6]) had reversion to episodic migraine during the double-blind treatment phase; of those, 96.9% (95% confidence interval: 91.3–99.4) had persistent reversion to episodic migraine, 96.8% (95% confidence interval: 91.1–99.3) of whom had long-term persistent reversion to episodic migraine. Delayed reversion to episodic migraine occurred in 36/83 (43.4% [95% confidence interval: 32.5–54.7]) patients; of these, 77.8% (95% confidence interval: 60.9–89.9) persisted in reversion through week 64. Conclusions Patients with reversion to episodic migraine at week 12 will likely persist as episodic migraine with longer-term erenumab; others may achieve delayed reversion to episodic migraine. Clinical trial registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02066415