Real-World Characteristics and Treatment Patterns of Calcitonin Gene-Related Peptide Monoclonal Antibody Users: a Japanese Claims Database-Based Study.

introductionUnderstanding real-world calcitonin gene-related peptide monoclonal antibodies' (CGRP mAbs) use in patients with migraine is necessary to potentially guide treatment strategies.

methodsThis retrospective cohort study analyzed administrative claims data from the IQVIA claims data for Japan. It included CGRP mAb-naïve individuals with confirmed migraine diagnosis and ≥ 1 CGRP mAb prescription (January 2021-June 2023). Index date was the first CGRP mAb prescription. Patient characteristics, treatment patterns, adherence (proportion of days covered ≥ 0.80), persistence, and migraine-related direct costs were assessed. Persistence was measured as the proportion of patients continuing treatment for ≥ 3 or ≥ 6 months (≤ 90-day gap between fills). Factors predicting adherence to CGRP mAb treatment were assessed using multivariate logistic regression. Subgroup analyses were conducted for galcanezumab users.

resultsOf the 1781 patients included (mean age 41.8 years [standard deviation, SD 10.3]; 79.3% female patients), 55.0% received galcanezumab, followed by fremanezumab (29.7%), and erenumab (15.3%). The prescription rates of concomitant acute and oral preventive medications were 86.1% and 51.3%, respectively, in the first 3 months after initiating CGRP mAb treatment but numerically decreased to 49.8% and 22.5%, respectively, in the fourth to sixth month. The index CGRP mAb persistence rates were 91.9% for ≥ 3 months and 76.9% for ≥ 6 months, and adherence rate was 51.7%. Multiple positive and negative predictors of adherence to CGRP mAbs were observed. Index to 3 months after initiating index CGRP mAbs, the median average monthly migraine-related costs were JPY 75,320 (Q1, Q3 61,593, 89,843) (USD 592), and non-CGRP mAb migraine-related costs were JPY 15,702 (Q1, Q3 8845, 27,848) (USD 123). These costs tended to reduce or plateau for up to 12 months thereafter. The galcanezumab subgroup showed a similar trend.

conclusionsCGRP mAb adherence and ≥ 6 months persistence rates were 51.7% and 76.9%, respectively, in CGRP mAb-initiating adults with migraine in Japan. During CGRP mAb treatment, acute and oral preventive medication prescription rates appeared to reduce, while direct costs initially increased but appeared to reduce from the post-initiation peak and plateau over time, although the underlying reasons could not be determined from claims data.