Fremanezumab is a Calcitonin gene-related peptide receptor antagonist (CGRP) monoclonal antibody currently under investigation for use in migraine. It has been filed for regulatory review in the EU.
A related commentary discusses this research. In addition to these findings on efficacy, fremanezumab appeared to be generally well tolerated over the 12-week study period. An important apparent benefit of fremanezumab and the other 3 CGRP monoclonal antibodies in development is their low burden of common nuisance adverse events. These agents offer the convenience and adherence benefits of monthly or quarterly dosing and are unlikely to produce drug interactions, an important consideration for patients with migraine who have other illnesses. Some current preventive treatments also are limited by a delay in onset of as long as months, whereas treatments like fremanezumab may work more rapidly
Despite these advantages, the long-term safety of the CGRP monoclonal antibodies remains unknown. Migraine often starts in early life and is a highly disabling but not fatal illness of long duration. If the CGRP monoclonal antibodies are approved by the FDA, patients will use them for far longer than the span of any clinical trials. Some concerns about safety are based on the known actions of CGRP, but off-target or unsuspected safety problems also could emerge.