Pharmacological differences and switching among anti-CGRP monoclonal antibodies: A narrative review

Antibodies targeting either the calcitonin gene-related peptide (CGRP), such as galcanezumab, fremanezumab, and eptinezumab, or the receptor (erenumab) have been approved for the prevention of episodic and chronic migraine. Although widely used and generally effective, a proportion of patients discontinue treatment due to lack of efficacy. In both randomized controlled trials and observational studies, all anti-CGRP monoclonal antibodies (mAbs) have consistently demonstrated comparable efficacy and tolerability, suggesting a pharmacological class effect. However, differences in therapeutic targets, structure, and pharmacokinetic characteristics may influence their efficacy and safety differently. Therefore, in patients not achieving a clinically meaningful response with one anti-CGRP antibody, switching to a different antibody may be a viable option. This review examines the pharmacological characteristics and distinctions among anti-CGRP mAbs, highlighting their mechanisms of action and pharmacokinetic profiles, along with the clinical observational data of switching. Finally, we summarize suggestions from international guidelines.