A migraine is more than just a headache. In addition to pulsating pain, people in the middle of an attack can experience nausea, vomiting, visual disturbances like tunnel vision, and sensitivity to light and sound.
The neurological condition is also incredibly common. Worldwide, one in seven people experience migraines—and as many as 20 percent of women in the United States and 10 percent of men get the neurological condition on a regular basis.
But as ubiquitous as they are, the treatments currently available are bleak. A class of drugs known as triptans—with brands names like Imitrex and Relpax—can successfully stop a migraine once it’s started, at least in many people. Until now, however, no drugs have been specifically designed to prevent a migraine in the first place. But last week, the Food and Drug Administration approved a treatment that does just that. The therapy’s mechanism of action has been in the works for decades, but took researchers a long time to crack.
Aimovig, developed in a partnership between drug companies Amgen and Novartis, is a once-monthly injection. It works by blocking a receptor that attaches to a neurotransmitter—known as the calcitonin gene related peptide (CGRP)—that researchers have found plays a key role in migraines.
What makes it so cool?
Neurologists and other migraine specialists have long awaited this new class of drugs.
It’s easiest to understand our lack of understanding about migraines by looking at the drugs we use to prevent them: all of them are borrowed from medicines developed to treat other conditions, and only used for migraines because doctors anecdotally found that patients reported fewer headaches. Doctors prescribe drugs designed to combat high blood pressure, seizures, and anxiety and depression in varying doses to treat migraine headaches. Unfortunately, those drugs also come with unwanted side effects, which often keeps patients from staying on their medication.
The newly-approved drugs follow a much more targeted approach. Back in the 1980s, researchers investigating migraines’ root causes zeroed in on the CGRP, a molecule that regulates nerve communication and helps control blood vessel dilation. Scientists found that those with migraines had markedly more CGRP molecules than those without. They also found that if they injected CGRP into people who were known to get migraines, that alone would trigger one. People without a history of migraines could get the same injection without experiencing a headache.
With this information, researchers quickly developed drugs to block CGRP, but the molecules themselves proved too toxic. That left them stuck for years. But recently, scientists tried a new approach, this time using monoclonal antibodies (immune cells that are made by cloning the exact same cell over and over again in a lab). These cells attach to receptors on the CGRP cells’ surface, rendering them useless to nerve cells.
But how good are they?
The key benefit of these new drugs is their targeted approach (aiming at the root cause of migraines) and their lack of drug-related side effects that are so prevalent in other current migraine-preventative treatments.
But their effectiveness—how good they are at preventing and mitigating migraine attacks—is still a matter of debate. In an editorial in JAMA that accompanied a study detailing the results of a recent trial of the drug, migraine specialists point out that in many cases the drug’s effect is modest, reducing the number of headaches a person gets by just 50 percent. Throughout the clinical trials researchers have reported a spectrum of results. For a select few patients—deemed ‘super responders’—the antibodies almost eliminated migraines completely. Some people didn’t respond at all, and most landed about in the middle, getting rid of half their headaches.
In JAMA, the researchers argue that it might not be the treatment itself that is failing, but rather that there are far more factors at play in regulating migraine. “It will be important to identify factors that predict treatment response and to evaluate the durability of responses,” the researchers write.
It’s also impossible to know, at least with the data currently available, whether the new treatment will be safe under its intended usage. Because migraines are a lifelong condition, people who take these drugs will likely take them for an extended period of time—for far longer than any clinical trial has run. Their safety in that kind of scenario remains unclear, and will stay that way until they’ve been around long enough for individuals to take them for decades. But this is true of any new drug for a chronic condition, and something that individual patients will have to weigh the risk of themselves (with the help of a physician).
When can I get it?
The new drugs are now FDA-approved and, according to Amgen, will be available starting this week. The once-monthly self-injections are costly, however. Just one dose is $575, which adds up to $6,900 a year. Amgen and Novartis are providing assistance programs to qualified patients that may bring the cost of the drug down to as little as $5 a month. Anyone with a valid prescription for Aimovig and commercial insurance qualifies, according to Amgen. However, the discount only applies until a patient has saved $2,700 in out-of-pocket costs. So people without insurance—or with high-deductible plans that had them paying large amounts directly to Aimovig for part of the year—would quickly max out on potential savings.
