One-Year Compliance After Calcitonin Gene-Related Peptide Monoclonal Antibody Therapy for Migraine Patients in a Real-World Setting: A Multicenter Cross-Sectional Study

<b>Background:</b> Calcitonin gene-related peptide monoclonal antibodies (CGRP mAbs) are a breakthrough migraine treatment, but long-term compliance under limited public insurance coverage has not been well known. This study explores one-year treatment patterns and outcomes of CGRP mAbs using real-world data. <b>Methods:</b> This multicenter retrospective study included migraine patients treated with CGRP monoclonal antibodies (CGRP mAbs) from July 2022 to June 2023. Treatment discontinuation was defined as a gap of over 60 days between injections. Among patients with 12 months of follow-up, adherence was measured using the Proportion of Days Covered (PDC), calculated as the ratio of days covered to the follow-up duration, with PDC ≥ 80% indicating good adherence. Efficacy was also assessed, defined as a ≥50% reduction in monthly headache days and acute medication use. <b>Results:</b> The study included 140 patients (mean age 44.6 ± 12.1 years; 82.9% female). Migraine without aura was predominant (93.6%), and 65.0% had chronic migraine. CGRP mAbs discontinuation occurred in 71.4% of patients, primarily due to headache improvement (22.9%) or lack of efficacy (15.0%). Among 81 patients with 12 months of follow-up, good adherence was observed in 40.7% of patients. Among these patients, 60.6% achieved a ≥50% reduction in monthly headache days, and 51.9% showed a ≥50% reduction in monthly acute medication use. <b>Conclusions:</b> More than two-thirds of patients discontinued the CGRP mAb within 1 year, so these findings emphasize the need for strategies to improve adherence and optimize follow-up plans to enhance patient support.