MMD (∆ 6.25, SE 1.21, p < .001), MHD (∆ 7.54, SE 1.62, p < .001), and AMD (∆ 4.26, SE 1.36, p = .005) increased significantly during the treatment break only among migraine patients who had previously obtained a 50% (50–74%) reduction in MMD following 12 months of CGRP (pathway) mAb treatment. The gene discussed is CALCA; the disease is migraine disorder.