Monoclonal antibody reduces acute headache medication use in refractory migraine sufferers

An investigational monoclonal antibody, erenumab, may reduce the use of acute headache medications and the number of monthly migraine days in patients with episodic migraine in whom previous treatments were not successful or who had intolerable side effects to those treatments, according to results from a phase 3b study known as LIBERTY.

In a separate investigation called STRIVE, erenumab also reduced the number of acute headache medication days/month (AHM) and the use of acute migraine-specific medications (AMSM) per month in patients with acute episodic migraine.

Erenumab is a fully human monoclonal antibody that selectively inhibits the calcitonin gene-related peptide (CGRP) receptor, which plays a critical role in migraine activation. Both sets of data were released at the 70^th annual meeting of the American Academy of Neurology (AAN) in April 2018.

In the multicenter LIBERTY study, investigators found that at 3 months, patients randomized to erenumab were nearly three times more likely to have reduced their migraine days by 50% or more than those in the placebo arm. Results from LIBERTY were presented by Uwe Reuter, MD, from The Charité-University Medicine, Berlin, Germany.

“Our study found that erenumab reduced the average number of monthly migraine headaches by more than 50% for nearly a third of study participants. That reduction in migraine headache frequency can greatly improve a person’s quality of life,” Dr. Reuter said.

For the LIBERTY study, Dr. Reuter and colleagues included 246 patients with episodic migraine who had experienced two to four preventive treatment failures due to lack of effectiveness or intolerable side effects. Patients were randomized to receive erenumab (140 mg) or placebo once monthly for 12 weeks.

Some 39% of patients enrolled had been treated unsuccessfully with two other medications, 38% with three medications, and 23% with four medications. At baseline, patients experienced an average of nine headaches per month and used an acute migraine drug an average of five times per month.

At 12 weeks, more than twice as many patients randomized to erenumab had their migraine days cut by at least 50% compared with placebo (30.3% vs 13.7%, OR: 2.73; P=0.002). There were also greater reductions in mean monthly migraine days and monthly acute migraine-specific medication days in patients randomized to erenumab compared with placebo.

In addition, patients treated with erenumab had an average 1.6 times greater reduction in migraine days and a 1.7 times greater reduction in acute medication days compared with those assigned to placebo.

No safety or tolerability concerns were observed in the erenumab arm, and no patient discontinued treatment due to side effects.

STRIVE was a placebo-controlled phase 3 trial that previously demonstrated that erenumab administered subcutaneously in a double-blind fashion for 6 months at doses of either 70 mg or 140 mg to patients with episodic migraine significantly reduced monthly migraine days vs placebo. Erenumab also reduced the number of days per month on which patients used AMSM compared with placebo.

The new STRIVE data reported by Dr. Reuter at the AAN meeting showed that erenumab significantly reduced AMSM days/month compared with placebo. The mean treatment difference was 1.57 (P < 0.001) fewer days per month in group assigned to 70 mg of erenumab vs placebo and 2.30 fewer days per month in the 140-mg erenumab arm vs placebo, averaged over months 4 to 6.