LOS ANGELES—Patients who have tried and failed other preventive therapies may find that erenumab can prevent their migraines, according to a study presented at the 70th Annual Meeting of the American Academy of Neurology. Erenumab is a fully human monoclonal antibody that inhibits the calcitonin gene-related peptide (CGRP) receptor.
Current oral preventive therapies are associated with low adherence rates due to their lack of efficacy or poor tolerability. Therefore, researchers thought it important to assess the safety and efficacy of erenumab in patients who had failed multiple therapies. A previous post hoc analysis of the STRIVE study showed that patients who had failed two prior preventives responded to erenumab. “Their odds ratio was far greater than [that of] those who were previous preventive naïve,” said Peter J. Goadsby, MD, PhD, who presented the newest erenumab data in the Emerging Science plenary session. Dr. Goadsby is a Professor of Neurology at Kings College London and the University of California, San Francisco.
“The people we included in our study were considered more difficult to treat, meaning that up to four other preventive treatments had not worked for them,” said lead study author Uwe Reuter, MD, Managing Director of Charité—University Medicine Berlin. “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.”
The LIBERTY Study
The LIBERTY study was a phase IIIb, randomized, double-blind, placebo-controlled trial thta assessed erenumab in patients who had failed at least two and not more than four prior preventives. A total of 246 patients with episodic migraine were randomized one to one to an injection of erenumab (140 mg) or placebo once per month for three months. There were 125 patients in the placebo arm and 121 in the erenumab arm. The primary end point was the proportion of patients achieving a 50% or greater reduction in mean monthly migraine days (MMDs) during weeks nine to 12 (ie, month three) of the study. Secondary end points included change from baseline to month three in MMDs and monthly acute migraine-specific medication days (MSMDs) and safety and tolerability.
At baseline, 39% of participants had been treated unsuccessfully with two other medications, 38% with three medications, and 23% with four medications. On average, participants had nine migraine days per month and used an acute migraine drug to stop an attack five times per month.
At week 12, the proportion of patients achieving a 50% or greater reduction in MMDs was higher in those treated with erenumab versus placebo (30.3% vs 13.7%). At week 12, there were greater reductions in MMDs and MSMDs with erenumab versus placebo. The safety and tolerability of erenumab were comparable to those of placebo. No patients in the erenumab group discontinued treatment due to adverse events.
Hope for Refractory Patients?
LIBERTY is the first dedicated study to address a problem that is all too common in neurology, said Dr. Goadsby. “It is hard to deal with patients who have failed prior preventives.” Erenumab, he said, is the first of the CGRP monoclonal antibodies to “control migraine and prevent migraine in patients who are so disabled and whom we cannot treat with current medicine.”
“Our results show that people who thought their migraines were difficult to prevent may actually have hope of finding pain relief,” said Dr. Reuter. “More research is now needed to understand who is most likely to benefit from this new treatment.”
The study was supported by Novartis Pharma.
—Glenn S. Williams