Calcitonin Gene-Related Peptide Monoclonal Antibody Utilization and Treatment Gaps in People with Migraine in Japan: Results from the OVERCOME (Japan) 2nd Study

BACKGROUND: Calcitonin gene-related peptide monoclonal antibodies (CGRP mAbs) are an effective preventive treatment for migraine. However, their population-level utilization patterns and treatment gaps are underreported in Japan. This analysis of the ObserVational survey of the Epidemiology, tReatment, and Care Of MigrainE (OVERCOME [Japan]) 2nd study, evaluated utilization patterns of CGRP mAbs and treatment gaps, and identified factors associated with CGRP mAb treatment experience among CGRP mAb-eligible individuals with migraine in Japan. METHODS: This analysis of a nationwide, population-based, cross-sectional online survey included adults with migraine. Respondents were further classified according to CGRP mAb eligibility (based on the guidelines for the promotion of optimal use). Both CGRP mAb-eligible and ineligible individuals were stratified by experience with CGRP mAbs. CGRP mAb-experienced respondents were further stratified into "current CGRP mAb" and "discontinued CGRP mAb" subgroups. Respondents reported their CGRP mAb utilization pattern, headache perceptions, attitude, and barriers to treatment initiation. Multivariate logistic regression was performed to identify the factors associated with CGRP mAb treatment experience among CGRP mAb-eligible respondents. RESULTS: Among the 19,590 respondents with migraine, 1484 (7.6%) met the eligibility criteria for CGRP mAbs (78 were current CGRP mAb users, 58 discontinued CGRP mAb, and 1348 never used CGRP mAbs), indicating about 90% of CGRP mAb-eligible individuals had never received CGRP mAb therapy. Among the 18,106 CGRP mAb-ineligible respondents, based on the current symptom status at the time of the survey, 110 were current CGRP mAb users, 176 discontinued CGRP mAbs, and 17,820 never used CGRP mAbs. In both the eligibility groups, more CGRP mAb-experienced respondents visited CGRP mAb-prescribable departments (63.6-88.5%). Among the CGRP mAb-eligible current users, most had consulted headache specialists (40.5%), and the proportion of triptan use (ever and current) was also high in these groups (84.6% and 73.1%). Among eligible nonusers (n = 1348), awareness of CGRP mAbs was markedly low (78.0% had never heard of CGRP mAbs), and only 4.2% had been informed about CGRP mAbs by a physician. Eligible nonusers were less likely to discuss treatment goals with physicians and more likely to perceive migraine as an unavoidable condition. Among the eligible respondents, CGRP mAb treatment experience was strongly associated with prior triptan use (OR 9.38 [95% CI 5.94, 14.80]), and consultation at the CGRP mAb-prescribing department (OR 7.20 [95% CI 3.60, 14.37]). CONCLUSIONS: A substantial treatment gap exists in the use of CGRP mAbs among eligible individuals with migraine in Japan. Improving access to specialist care, enhancing patient-physician communication, and increasing awareness of preventive treatment options are critical to address the unmet treatment needs.