The FDA just approved a migraine treatment that's the first of a new class of medications.

The drug is called Aimovig, and it's made by Amgen in partnership with Novartis. It will cost US$6,900 a year.

The wave of new treatments, of which Aimovig is the first to get approval, are going after the huge migraine market. An estimated 38 million Americans have migraines, and around a third of those people would be eligible for preventive treatment.

And while there aren't any drugs available today that were originally approved for alleviating migraines, other treatments – including Botox and anti-seizure medications – are used.

Pain relievers can also help treat some of the symptoms of migraines.

The drug – and its competitors – target CGRP, short for calcitonin gene-related peptide.

CGRP isn't exactly a new target. CGRP has been known to play a significant role in migraines since the 1980s and 1990s, though it's taken some time to develop the technology that can leverage it.

In data released in June 2017, Amgen said its drug was able to reduce the number of migraine days per month by 6.6 days in patients who received the treatment, compared to a 4.2-day reduction in the placebo group.

Before the trial, patients had about 18 migraine days.

Aimovig is one of a handful of preventive migraine drugs, with a handful also in front of the FDA for review.

Lilly, galcanezumab

Lilly presented phase 3 data in June. The company found in two studies that patients on the drug had between a 3.6 and 4-day reduction in migraine days per month (to be eligible, patients had to have between 4 and 14 migraine days per month).

That's compared to the 2.15 and 1.85 day reduction that was observed in the placebo groups. Lilly filed galcanezumab with the FDA in December.

Teva, fremanezumab

In June 2017, the company came out with data from its late-stage trial. On average, the trial participants had 9.1 migraine days.

Those who got the medication had on average 3.7 fewer migraine days per month, compared to 2.2-day reduction in the placebo group. Teva filed with the FDA in October.

Alder Biopharmaceuticals, eptinezumab

Alder's drug, which would be administered on a quarterly basis, succeeded in phase 3 trials, the company said in January. The company plans to submit to the FDA in the second half of 2018.

Allergan, atogepant

Allergan is developing CGRP- targeting drugs to both treat migraines when they're happening and prevent them. Atogepant, the company's preventative treatment, is currently in phase 2 clinical trials.

The new class of drugs aims to reduce the number of days per month people have migraines. If approved, the drugs are expected to cost US$8,500 per year.

Pharmaceutical middleman Express Scripts is putting pressure on the makers of these drugs to forgo higher list prices and get refunded if the drugs don't work over a set period of time.

This article was originally published by Business Insider.

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