Three-Year Safety Analysis of Erenumab Treatment for Episodic Migraines

For patients with episodic migraines, erenumab was found to have a favorable tolerability and safety profile, according to a 3-year interim safety update published in Cephalalgia.

Researchers reported on a 3-year interim safety report of a 5-year open-label study that followed a 12-week double-blind treatment phase of erenumab for patients with episodic migraine. The treatment phase included an erenumab 7 mg per month cohort, an erenumab 21 mg per month cohort, an erenumab 70 mg per month cohort, and a placebo cohort. The patients who entered the open-label treatment phase were given 70 mg erenumab originally before a protocol amendment increased the dosage of erenumab to 140 mg per month to assess higher dose safety. The safety and tolerability study outcomes are rates of adverse events, electrocardiograms, changes in laboratory assessments, and changes in vital signs.

At the time of this report, 236 patients have been included in the study. The incidence rate for adverse events was 132 per 100 patient-years; the most frequently reported were viral upper respiratory tract infection, upper respiratory tract infection, sinusitis, influenza, and back pain, and none of these were at a rate higher than the placebo-controlled arm during the double-blind treatment phase of this study. The incidence rate for serious adverse events was 4.2 per 100 patient-years; the most frequently reported were adjustment disorder, syncope, uterine leiomyoma, and breast cancer. There were no meaningful changes in blood pressure or heart rate, or any suspected cases of Hy’s law, although 8 patients experienced alanine aminotransferase or aspartate aminotransferase more than 3 times the upper limit of normal. Nonneutralizing binding antibodies developed in 38 patients during the double-blind treatment phase or the open-label treatment phase, with only an additional 2 developing non-neutralizing binding antibody over the long-term follow-up.

A limitation of this study includes the lack of a placebo cohort for the long-term safety assessment.

The researchers concluded that “erenumab was found to be safe and well-tolerated with a spectrum and rate of adverse events consistent with shorter-term placebo-controlled studies.”

This study was funded by Amgen Inc. and many authors report multiple associations with other pharmaceutical companies. Please see the original reference for a full list of authors’ disclosures.

Reference
Ashina M, Goadsby PJ, 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