SAN FRANCISCO – After a lengthy drought in the development of major new headache medications, it was finally raining successful phase 3 clinical trials for novel drugs at the annual meeting of the American Headache Society.
Bruce Jancin/MDedge News
Dr. Richard B. Lipton
From the podium, as a prelude to presenting one of many positive trials, Richard B. Lipton, MD, was moved to paraphrase Charles Dickens: “ ‘It was the best of times’ ... and these are truly the best of times,” the neurologist observed.
“This morning we’ve heard about seven new molecular entities that are effective in the acute and/or preventive treatment of migraine, a couple of novel ways of delivering older drugs, and some interesting comparative effectiveness research. I have this compulsion to say over and over again – because I also work in Alzheimer’s disease – it just isn’t like this in other fields. This is truly a remarkable time in our field,” observed Dr. Lipton, professor and vice chair of the department of neurology at Albert Einstein College of Medicine in New York.
In addition to new studies of erenumab-aooe, which has been approved as Aimovig, the first-in-class calcitonin gene-related peptide (CGRP) inhibitor for the preventive treatment of migraine, the headache meeting also featured new positive phase 3 results for three other anti-CGRP monoclonal antibodies – galcanezumab, fremanezumab, and eptinezumab – as migraine-preventive therapy, with galcanezumab also demonstrating efficacy in episodic cluster headache; the oral small-molecule CGRP antagonists rimegepant and ubrogepant for acute treatment of migraine attacks; and the selective serotonin 5-HT 1F agonist lasmiditan, also for acute treatment of migraine.
Although the mechanisms of action and therapeutic purposes of the novel agents differ, they share in common what appears to be far better safety and tolerability than the current market leaders, topiramate (Topamax) for migraine prevention and the triptans for acute treatment.
Here are study highlights for the three potential new treatments for acute migraine attacks:
Rimegepant
Dr. Lipton presented the results of two virtually identical phase-3, double-blind, randomized trials in which a total of 2,162 patients with episodic migraine self-administered a 75-mg oral tablet of rimegepant or placebo to treat a single migraine attack when their headache pain reached moderate or severe intensity. The clinical trials, which lacked the customary snazzy acronyms, were simply called Study 301 and Study 302.
The two co-primary endpoints now required by the Food and Drug Administration for candidate agents for acute treatment of migraine attacks are freedom from pain and absence of the most bothersome symptom, both as assessed 2 hours post dose. The oral CGRP receptor antagonist met both endpoints, as well as key secondary endpoints.
In Study 302, for example, the pain-free rate 2 hours post dose was 19.6% in the rimegepant group, significantly higher than the 12% rate in placebo-treated controls. The rate of freedom from the most bothersome symptom, which was photophobia in the majority of patients, was 37.6% in the rimegepant group and 25.2% with placebo.
Dr. Lipton characterized the benefits seen with a single dose of rimegepant as “broad and clinically important.”
“The majority of patients achieved pain relief, durability of benefit at 24 and 48 hours, lower use of rescue medications, and a greater proportion of patients achieved normal function,” the neurologist reported.
The safety and tolerability profiles of rimegepant mirrored those of placebo, he added.