FDA approves migraine drug as the first cluster headache treatment

As many as 1 million Americans who suffer with cluster headaches may finally get some relief with the approval of the first drug specifically designed to treat the rare but devastating condition that affects mostly younger men.

Patients often have to take medications that have significant side effects such as swelling of the legs. But on Tuesday, the Food and Drug Administration approved a new treatment — a once monthly injection, Emgality, made by Eli Lilly.

In a recent clinical trial, the drug was shown to significantly reduce the number of cluster headache attacks — from an average of eight headaches per week to five per week — with few side effects.

“Emgality provides patients with the first FDA-approved drug that reduces the frequency of attacks of episodic cluster headache, an extremely painful and often debilitating condition,” Dr. Eric Bastings, deputy director of the division of neurology products in the FDA’s Center for Drug Evaluation and Research, said in a press release.

Emgality belongs to a new class of drugs called CGRP inhibitors that are used to prevent migraines or reduce their frequency. It's one of three drugs in this drug class for migraines that have been released in the past year.

“The study wasn't very long, it was only for three weeks, but these drugs are interesting and have a lot of potential,” Dr. Alan Shepard, neurologist and headache specialist at Northwestern Memorial Hospital, said. “Its something we will be trying more in the future.”

“Cluster headaches are 90 percent more common in men ages 30 to 40,” Shepard said. But despite the small subset of people that the condition affects, doctors are very excited about the drug's approval.

“The drugs seem to be safe and effective and most neurologists will probably start using these for different types of headaches,” he added.

According to the American Migraine Foundation, cluster headaches, which are a subtype of migraines, most often occur between the ages of 20 and 40, and they may affect as many as 1 million people in the United States. However, no exact number has been determined by researchers.

Like migraines, they cause intense pain and an inability to function much at all when they strike. Unlike migraines, which tend to be more prevalent in women, the condition is slightly more common in men.

Fewer than 1 percent of people have cluster headaches. Most patients have a form called episodic cluster headaches, which come and go, in periods or cycles, the American Migraine Foundation says. Sufferers can go months without an attack and then have several sudden headaches — each one lasting anywhere from 15 minutes to three hours — in a single day or over several days. They commonly occur overnight, waking people up from sleep.

The condition often goes undiagnosed because it is associated with symptoms common to other conditions, such as bloodshot eyes, excessive tearing, drooping eyelids and nasal congestion.

The medications currently used to treat cluster headaches include drugs used to treat heart and psychiatric issues. Often these drugs are prescribed in high doses and cause side effects, such as leg swelling, said Dr. Dario Zagar, president of the Associated Neurologists of Southern Connecticut.

The self-injected migraine treatment is a solution which needs to be administered once a month. Patients will be given a 300 milligram monthly dose, compared with a 120 mg per month dose for migraine prevention. The price of the drug will cost roughly $7,000 per year although the cost may vary depending on the length of the treatment.

“A once-monthly injection is a welcome sight especially for young patients who are on the current medications we use which potentially have quite a number of side effects,” Zagar said.

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