Erenumab, First Novel CGRP Inhibitor, Gains FDA Approval for Migraine Prevention

May 18, 2018

The first-in-class anti-CGRP monoclonal antibody erenumab has gained FDA approval for the prevention of migraines.

Eric Bastings, MD

The first-in-class anti-CGRP monoclonal antibody erenumab (Aimovig) has gained FDA approval for the prevention of migraines, based on findings from 3 clinical trials showing a dramatic improvement with the once-monthly self-injectable.

The first study, known as STRIVE, included 955 patients with episodic migraines. In this trial, erenumab reduced the number of migraine days per month by 3.2 with a 70-mg dose and by 3.7 with a 140-mg dose, which was nearly double the rate of reduction compared with placebo, which had a reduction of 1.8 days, according to findings published in the New England Journal of Medicine.

A 50% or greater reduction in migraine days per month was achieved for nearly half of patients treated with erenumab (43.4% and 50.0%) compared with just 26.6% with placebo (P <.001). The baseline number of migraines experienced by patients in the STRIVE study was 8.3.

“Aimovig provides patients with a novel option for reducing the number of days with migraine,” Eric Bastings, MD, deputy director of the Division of Neurology Products in the FDA’s Center for Drug Evaluation and Research, said in a statement. “We need new treatments for this painful and often debilitating condition.”

In addition to fewer migraines, treatment with preventive erenumab lowered the need for acute migraine-specific medication in the STRIVE trial. In the 70-mg group, there was a 1.1-day reduction in the need for acute medication and in the 140-mg arm there was a 1.6-day reduction. In the placebo arm, there was just a 0.2-day reduction.

Improvements in physical impairment scores were nearly double in the erenumab arm compared with placebo. In the lower dose arm, there was a 4.2-point improvement and with the 140-mg dose there was a 4.8-point increase. With placebo, there was a 2.4-point improvement. Everyday activity scores were also improved with erenumab, by 5.5 and 5.9 points in the 70-mg and 140-mg erenumab groups, respectively, versus 3.3 points in the placebo group.

Similar benefits were observed in the second phase 3 study that led to the approval, which was known as ARISE. This study included 577 patients with episodic migraines, with a 2.9-day reduction in migraine days per month with erenumab compared with a 1.8-day reduction with placebo. Acute medications usage was also reduced with the antibody.

The third study included 667 patients with chronic migraine. This phase 2 study showed a 6.6-day reduction with both doses of the medication compared with a 4.2-day reduction for placebo. Patients in this study had 18 migraine days per month at baseline. The use of acute medication was reduced by 5.4 days for erenumab at 70 mg and by 4.9 days for the 140 mg dose compared with a 2.1-day reduction for placebo.

Across studies, the benefits of erenumab were sustained for up to 15 months. Adverse events were comparable in the placebo and treatment groups, with a slight increase in injection site reaction and constipation with the monoclonal antibody, according to the FDA.

"Having a treatment designed to specifically address the complex nature of migraine is an important and welcome step forward in headache medicine. Aimovig offers self-administration with proven efficacy across a spectrum of patients, including in those who have previously tried other preventive therapies without success," Stewart J. Tepper, MD, Professor of Neurology at the Geisel School of Medicine at Dartmouth Medical School, said in a release. "Importantly, in clinical trials, Aimovig patients were able to start and stay on therapy — with a discontinuation rate of 2% due to adverse events – and experienced sustained migraine prevention."

Erenumab was codeveloped by Amgen and Novartis. The companies announced that the injection would be available in a 70 or 140-mg single-use prefilled autoinjector at $575 a month ($6,900 annually). The companies noted that out of pocket costs would vary based on insurance providers but could be as low as $5 per month for some patients.

"The FDA approval of Aimovig reflects the Novartis commitment to advancing neuroscience and marks an important moment in the fight against migraine," Fabrice Chouraqui, US President of Novartis Pharmaceuticals Corporation, said in a statement. "Migraine is a serious and misunderstood disease with significant gaps in the way it is both perceived and treated. In close partnership with Amgen, our goal in the US is to bring meaningful therapeutic options to patients, while also helping them to overcome the personal, professional and clinical barriers that have long been associated with this stigmatized disease."

The implications of erenumab's approval is amplified by the scope of how it affects a massive patient population. According to the Migraine Research Foundation, about 1 in every 8 people in the world suffer from migraines. Prior to the clinical investigation of CGRP inhibitors, the only US marketed therapy specifically for chronic migraines was onabotulinumtoxin A (Botox).