Amgen won U.S. Food and Drug Administration approval on Thursday for the first drug to prevent migraine headaches in adults.

The drug, Aimovig, which is given monthly by self-injection, will have a list price of $6,900 a year, or $575 a month, the company said. Any discounts or rebates will depend on negotiations with health plans, Amgen spokeswoman Kristen Davis said.

Aimovig is the first in a new class of treatments designed to prevent migraine by interfering with calcitonin gene-related peptide (CGRP), which is involved in the processes that kick off a migraine, such as dilation of blood vessels in the brain.