In 2018, the United States Food and Drug Administration (FDA) approved Aimovig 
(erenumab) for the prevention of migraine. Erenumab is the first FDA approved 
antibody therapeutic against a G-protein-coupled receptor, the canonical 
receptor of calcitonin gene related peptide (CGRP-R). A novel, epitope-focused 
antigen was created to reconstruct the extracellular domains of the CGRP-R in a 
stable conformation. Successful inoculation of XenoMouse animals and careful 
screening yielded multiple candidate molecules for high potency and exquisite 
selectivity toward the CGRP-R over related receptors. These efforts led to the 
discovery of erenumab which has demonstrated the desired efficacy and safety 
profiles in multiple clinical studies for the prevention of migraine. The 
innovation developed in the discovery of erenumab furthers the ability to target 
G-coupled protein receptors using antibody approaches.