Long-Term Effectiveness and Persistence Factors of Anti-CGRP Monoclonal Antibodies in Migraine

Objectives – The aim of this study was to describe the long-term effectiveness and treatment persistence of anti–calcitonin gene-related peptide (CGRP) monoclonal antibodies (MAbs) in migraine and to identify baseline factors associated with 2-year treatment continuation.Methods – A prospective observational multicenter registry-based study of anti-CGRP MAbs was conducted. We analyzed changes in monthly headache days (MHDs) at 24 months (M24) compared with baseline in those who reached M24 (ON-group). We analyzed patterns of response at 4 time points (6, 12, 18, and 24 months). We defined sustained response (SR) as a ≥50% reduction in MHDs at ≥3 of 4 time points. We compared baseline characteristics of the ON-group with those of the discontinuation group because of lack of effectiveness (OFF-group).Results – A total of 1, 340 individuals reached M24 (ON-group: median age 48.0 [41.0–55.0] years; 81.7% female). The median MHD at baseline was 20.0 (13.0–28.0) days. At M24, 60.4% of patients demonstrated ≥50% reduction in MHDs (809/1, 340). The proportion of participants achieving SR at M24 was 53.8% (142/264). When compared with the ON-group (n = 1, 340), the OFF-group (n = 1, 057) showed statistically significant higher baseline MHDs (ON: 20.0 [13.0–28.0] vs OFF: 25.0 [16.0–28.0]) and a greater proportion of patients with aura (ON: 16.2% vs OFF: 22.9%), depression (ON: 22.8% vs OFF: 37.9%), and obesity (ON: 7.2% vs OFF: 19.1%) (p < 0.001).Discussion – Sustained reductions in MHDs to anti-CGRP treatment at 2 years was observed. Delayed treatment onset, migraine with aura, depression, and obesity may negatively affect treatment persistence.Classification of Evidence – This study provides Class IV evidence that, in patients with migraine, treatment with anti-CGRP MAbs is associated with sustained reductions in MHDs over a 24-month period.