The FDA approved Novartis and Amgen’s Aimovig (erenumab-aooe), making it the first agency-approved preventive migraine treatment in a new drug class that blocks the activity of calcitonin gene-related peptide, a molecule involved in migraines.

The medicine’s effectiveness was evaluated in three clinical trials. In one 667-patient trial, those treated with the medication experienced two and a half fewer monthly migraine days on average.

The trials determined that the medication significantly reduced migraine frequency, the effects on daily activities and the use of acute migraine-specific medication over a period of six months.