Historically, the treatment of migraine has largely been based on managing symptoms, as the root cause of migraine was not fully understood. It is estimated that about half of individuals with migraine self-medicate with over-the-counter medicines.
Broadly, there are currently two groups of medicines used to treat migraine:
Acute medicines
The goal of these treatments is to achieve a rapid, consistent and complete relief from symptoms after their onset. The most commonly used medicines are analgesics that relieve the pain and antiemetics that relieve the nausea associated with migraine attacks.
Preventive medicines
Preventive treatments can reduce the number of migraines experienced by a patient each month, which is especially beneficial for people who experience them frequently. Preventive medication can also help avoid the overuse of acute pain relief medication.
Many of the existing preventive treatments are repurposed drugs that were generally developed for other diseases. As a result of poor efficacy and tolerability, the majority of people living with migraine choose to discontinue these treatments within a year.
Novel migraine preventive treatments are molecules that work by blocking the calcitonin gene-related peptide (CGRP), or its receptor, to reduce the number of migraine attacks. CGRP is a molecule that binds to the CGRP receptor complex and is thought to be responsible for transmitting the pain signals associated with migraine. In addition, it has been found that the levels of CGRP in people experiencing migraines increase at the onset of migraine symptoms, and return to normal when the migraine pain subsides. CGRP has therefore been the therapeutic target of recent and upcoming migraine treatments.