Erenumab Approval Ushers In New Era of Migraine Prevention Therapy

CGRP inhibitor therapies have shown long-term efficacy, safety, and tolerability profiles at the clinical stages — and erenumab is just the first of them to reach the market.

Stephen D. Silberstein, MD

The US Food and Drug Administration’s (FDA) approval of erenumab (Aimovig) for the prevention of migraines in adults on Thursday was a historical indication. In due time, it may be remembered as only the start of a new standard in migraine care.

The therapy, to be codeveloped by Amgen and Novartis, was backed on the results of 3 clinical trials that showed reductions in the number of migraine days per month, acute migraine-specific medication taken by patients, and physical impairment in patients taking either indicated doses (70 or 140 mg). When it comes to the market next week, single-use prefilled autoinjectors will be available at $575 a month, or $6900 annually, according to the companies. That out-of-pocket cost could become as low as $5 per month for some patients.

An accessible migraine therapy with proven efficacy and safety over long-term studies — as well as a reported discontinuation rate of just 2% in participating patients — is something novel to the field.

“Having a treatment designed to specifically address the complex nature of migraine is an important and welcome step forward in headache medicine,” Stewart J. Tepper, MD, Professor of Neurology at the Geisel School of Medicine at Dartmouth Medical School. “Aimovig offers self-administration with proven efficacy across a spectrum of patients, including in those who have previously tried other preventive therapies without success.”

The isolated implication of its 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 monoclonal antibodies such as erenumab, galcanezumab, fremanezumab, and epitnezumab, the only US marketed therapy specifically for chronic migraines was onabotulinumtoxin A (BOTOX).

“We’ve been the redheaded step-children of medicine,” Julie Bryson, MD, migraine neurologist at Wake Forest Baptist Medical Center told MD Magazine last year.

Such limitations are no longer an issue. While attending the 70th annual meeting of the American Academy of Neurology (AAN) in Los Angeles, CA, Stephen D. Silberstein, MD, director of the Jefferson Headache Center at Thomas Jefferson University, told MD Magazine that the progression of calcitonin gene-related peptide (CGRP) inhibitors for migraine prevention is the first time in a long time the field has come across good news.

“(This is all) based on the concept there’s too much CGRP floating around and we can neutralize it with small molecules that can block where it goes, and other drugs that can suck it up,” Silberstein said.

Silberstein added that CGRP inhibitors, with a known method of action, create a paradoxical effect in patients: the more patients take, the less migraines they will experience.

“So not only is it safe and effective, it’s anti-rebound headache,” Silberstein said. “You take too many triptans, you wake up with a headache. You take too many of these, your headaches are going to go away for a while.”

Erenumab’s reduction of monthly migraine days — its primary endpoint in critical trials that led to its approval — is itself a novel option patients can consider when being treated for migraines, said Eric Bastings, MD, deputy director of the Division of Neurology Products in the FDA’s Center for Drug Evaluation and Research. But more and more new treatments are needed for the vast, debilitating condition.

Depending on when rival CGRP inhibitors are able to reach the market, migraine prevention can become one of the most rapidly-growing fields of care in the US.

“This new class of drugs, to the best of our knowledge, looks entirely clean,” Silberstein said.

The Clinical Focus condition center at NeurologyLive, MD Magazine's new sister site, provides even more extensive coverage pertaining to headaches and migraines, as well as updates from the field’s most prominent conferences.