Calcitonin gene-related peptide targeted immunotherapy for migraine: progress and challenges in treating headache.

A role for calcitonin gene-related peptide (CGRP) in the pathophysiology of migraine has been established over the past 25 years. There have now been at least five different small-molecule CGRP antagonists that have demonstrated statistical proof of efficacy in the acute treatment of migraine. At present, multiple clinical trials are underway that are assessing the ability of long-acting antibodies against CGRP to prevent frequent migraine attacks. This review summarizes the existing data concerning the role of CGRP in migraine and attempts to highlight some possible outcomes from the ongoing anti-CGRP antibody trials.