Until this year, migraine sufferers had to make do with drugs originally developed for other medical conditions, such as high blood pressure or depression. Now, there are three new drugs that were developed just for preventing the horrible headaches.
Erenumab (Aimovig) was approved by the FDA in May. Fremanezumab (Ajovy) was approved in September and is now available. Galcanezumab (Emgality) was approved late in September and began arriving in doctors' offices this week.
"They have a lot of promise and are potentially very important," said Katherine Hamilton, a headache specialist at Penn Medicine. The drugs, which are injected under the skin, offer hope for patients who have not responded to other treatments, but Hamilton said that what is "potentially even more clinically relevant is they have a lower side-effect profile" than other medications commonly used for migraine. She added, though, that it remains to be seen how patients who take them for long periods will fare. As new drugs, their long-term impact is not yet known.
Stephen Silberstein, director of the Jefferson Headache Center, said about 800 of his migraine patients are on a list to start taking the drugs. He was involved in testing erenumab and helped design and run the trial for fremanezumab, so many of his patients were involved in the clinical trials and have already tried the medicines.
Silberstein said insurance is expected to offset erenumab's price tag, about $600 a month, but patients will be eligible only if they have tried other drugs first and found they didn't help. He and Hamilton said some other migraine drugs have similar costs.
Louis Colburn, 71, a retired police officer and security manager who gets migraines most days of the week, was among the first of Silberstein's patients to try fremanezumab. His headaches, he said, are "just like somebody's got a drill inside your brain." He watched calmly last week as nurse practitioner Rachel Seligman emptied three syringes under the skin of his left thigh.
The shots should last three months. Silberstein said Colburn should see results in a week. He expects that patients with frequent headaches won't mind getting three shots at once. "If you realized how bad a migraine headache is, the shots don't matter," he said.
Migraines affect 40 million people in the United States. These drugs were tested in people with chronic migraines, defined as 15 or more headaches a month. One percent to 2 percent of the population falls into that category.
The new drugs are monoclonal antibodies aimed at CGRP (calcium-gene-related peptide), a string of amino acids that play a role in how people experience pain, and must be injected. All can be taken monthly, but fremanezumab has the advantage of also having the option of quarterly shots. The drugs have different mechanisms, but they prevent CGRP from working normally. Another drug that targets CGRP and will be given intravenously is in development, Silberstein said.
Competition may bring costs down, he said.
CGRP is elevated during migraine headaches. It also is involved in the movement of food through the gut and is present in the heart and blood vessels. Researchers were concerned that the drugs might cause systemic problems, but Silberstein said mild constipation was the most serious side effect of the drugs in the trials.
He said the drugs appeared to be equally effective. About half the patients had a 50 percent or greater reduction in the number of headaches they experienced. Almost three-quarters had at least a 30 percent reduction. The overall averages look less exciting, however. Chronic migraine patients had about two fewer headache days a month than those who took placebos. The placebo group had a small reduction in headaches, too. In the treatment groups, the intensity of the headaches also went down.
Silberstein said the drugs were helpful for patients who responded. "I've had patients already on these drugs who went from not being able to function to having almost a normal life," he said.