Study Results Suggest Long-Term Safety of Erenumab for Treating Migraine

An interim analysis of erenumab—a human anti-calcitonin gene-related peptide (CGRP) receptor monoclonal antibody used for migraine prevention—continued to be safe and well-tolerated, with an adverse event profile consistent with shorter-term placebo-controlled studies, according to a recent study.

The research, published by Cephalalgia, involved an interim analysis of an ongoing 5-year open-label treatment phase after all patients completed 3 years in the open-label treatment phase or discontinued the study. The study enrolled adult patients with episodic migraine in the open-label treatment phase; they initially received 70 mg of erenumab monthly.

“Migraine is a long-lasting disorder whose attack frequency fluctuates in the individual patient. Some patients need to be on preventive therapy for many years, requiring that treatments have favorable longterm risk benefit profiles,” explained the authors. “Multiple studies have provided clinical evidence on the efficacy and safety of investigational monoclonal antibodies targeting the calcitonin gene-related peptide (CGRP) receptor or the ligand itself, but to date there have been no studies assessing long-term tolerability and safety of these treatments beyond one year”.

The dosage increased to 140 mg monthly due to a protocol amendment that would test long-term safety of the higher dose. According to the study, researchers evaluated the safety and tolerability of the drug by monitoring adverse events, electrocardiograms, laboratory assessments, and vital signs.

In total, 383 patients enrolled in the open-label treatment phase; however, at data cutoff, 235 remained in the study and received the 140 mg dose for at least 1 year. The results revealed that the most frequent adverse events reported were viral upper respiratory tract infection, sinusitis, influenza, and back pain. In addition, exposure-adjusted serious adverse event rates were 4.2/100 patient-years, yet there was no increase in cardiovascular events over time.

“In this three-plus years, long-term study of an antibody targeting the CGRP receptor, erenumab was found to be safe and well-tolerated with a spectrum and rate of AEs consistent with shorter-term placebo controlled studies,” concluded the authors. “The favorable tolerability and safety profile, and the low discontinuation rates, suggest that adherence is favorable with erenumab and may result in positive long-term outcomes.”

Reference

Ashina M, Goadsby P, Reuter U, et al. Long-term safety and tolerability of erenumab: Three-plus year results from a five-year open-label extension study in episodic migraine [published online May 30, 2019]. Cephalalgia. doi: 10.1177/0333102419854082