Two new migraine prevention drugs show promise in small studies
There are few treatments available for the millions of people who suffer from migraines. New early-stage research offers new hope.
Studies presented Tuesday at the American Academy of Neurology’s annual meeting suggest that two new drugs may prevent migraines from happening.
“We’ve identified a new preventive treatment for migraines, something that reduces frequency, the number of attacks and severity of attacks, how bad the attacks are,” said Dr. Peter Goadsby, co-author of both studies and professor of neurology at Kings College, London and the University of California, San Francisco. “The results herald a new mechanism for the preventive treatment of migraines.”
That mechanism involves a protein called calcitonin gene-related peptide, or CGRP. CGRP is one of the key chemicals that causes the debilitating effects of a migraine. Both drugs work by blocking CGRP and therefore stopping the migraine from starting.
Both drugs are genetically engineered antibodies, a class of drug that’s been used in cancer treatments, but not yet for migraines.
One drug called ALD403 was tested for safety and efficacy in 163 patients, who typically spent 5 to 14 days per month suffering from migraines. Half got one 1000 mg intravenous dose of ALD403; the other half got a placebo. They were followed for 6 months. Within 2 months, patients on the drug saw a 66% reduction in the number of days they suffered migraines. They had on average nearly 6 more migraine-free days each month, compared to a 52% decrease (or just under 5 days) in those who got the placebo.
At 12 weeks, 16% of the patients who got the ALD403 were free of migraines. Those on the placebo were not.
The other promising drug is called LY2951742. It too was found to be a safe and effective migraine treatment. In that study, 217 patients who had migraines 4 to 14 days per month got a 150 mg injection of LY2951742 every two weeks for 12 weeks. Those who got the shots saw about a 4-day reduction (or 63%) in the number of days with migraines, compared to a 42% decrease for those who got the placebo.
Goadsby and Dr. David Dodick, co-authors of both studies, say this treatment is exciting because it’s entirely new and specific to migraines. Dodick, a professor of neurology at the Mayo Clinic and Chairman of the American Migraine Foundation, said no drugs targeting the treatment of migraines have been developed in the past 50 years.
“Presumably if you’re targeting the very protein responsible for an attack, you should have fewer side effects than (with) drugs which were designed to treat some other disease, and all drugs currently available for the prevention of migraines were designed to treat another disease.”
While there was no difference in the side effects reported by patients taking ALD403 and the placebo, patients getting LY2951742 reported side effects including pain at the injection site, abdominal pain and upper respiratory tract infections. Still, researchers say the drug is safe and well tolerated.
The studies are good news for migraine specialists such as Dr. William Young, a professor of neurology at Thomas Jefferson University in Philadelphia, Pennsylvania.
“I’m impressed. We haven’t had a well proven preventive for episodic migraines like this since Topomax and Botox for chronic migraine,” says Young.
He says a quarter of his patients cannot hold down a job because of their migraines, and the condition is often stigmatized.
Why are there so few good treatments for migraines? Young, Goadsby and Dodick all point to the lack of funding of migraine research by the National Institutes of Health.
“There is an appalling, appalling under-resourcing of migraine research by government bodies such as NIH, Goadsby said. “There are 36 million Americans with migraines and on average the NIH spends about 30 US cents per migraine patient per year.”
Dr. Linda Porter, a Pain Policy Advisor at the NIH’s National Institute of Neurological Disorders and Stroke said “I would agree that we really do not spend a lot of research dollars on migraine and headache, but we do understand that it’s an incredibly significant health care problem and that chronic migraines can be very disabling for many people.”
In a statement to CNN, NIH characterized the funding issue as “a little bit complicated.”
“Our entire pain portfolio is $400 million dollars, that includes anything from osteoarthritis to cancer pain,” the statement said, “and so one of the difficulties that we have faced over the years in funding headache research is that the field of researchers is very small.”
Porter says more research dollars aren’t allocated to studying pain because of the few research applications they receive. “Over the past 10 years we have made great efforts to give funding priority to new or junior investigators in headache research to try to expand the field of researchers and thus expand the research portfolio.”
A lot of the basic science on the molecule (CGRP) which is used in these new drugs was funded by NIH, Porter said. She says the NIH is excited about these new studies.
But the drugs need to be tested in large scale clinical trials, and receive FDA approval, before patients can access them. Researchers estimate that’s at least 3 years away.