Real-world treatment persistence in csDMARD-IR and bDMARD-IR patients with rheumatoid arthritis in Japan: A large claims database study.

Objectives: To investigate treatment persistence for biologic disease-modifying antirheumatic drugs (bDMARDs) and Janus kinase inhibitors (JAKis), including filgotinib, in Japanese patients with rheumatoid arthritis (RA) who have an inadequate response (IR) to conventional synthetic DMARDs (csDMARD-IR) and bDMARDs (bDMARD-IR), and to identify characteristics associated with treatment discontinuation.

Methods: We analyzed 2020-2023 health claims data from adults with RA who received ≥1 prescription for bDMARDs or JAKis during the study period and ≥1 prescription for csDMARDs over the previous 6 months. Persistence rates were estimated for the csDMARD-IR (patients naïve to bDMARDs/JAKis) and bDMARD-IR (patients switching to bDMARDs/JAKis from an initial bDMARD) cohorts using the Kaplan-Meier method.

Results: Overall, 7208 and 1581 patients were identified in the csDMARD-IR and bDMARD-IR cohorts, respectively. In the csDMARD-IR cohort, 1-year persistence rates were 59%-70% for JAKis (67% for filgotinib) and 53%-69% for bDMARDs. In the bDMARD-IR cohort, 1-year persistence rates were 57%-66% for JAKis (66% for filgotinib) and 19%-91% for bDMARDs. No clinical characteristics were consistently associated with the persistence of JAKi or bDMARD treatment.

Conclusions: Rates of persistence among patients taking JAKis, including filgotinib, were approximately 60% or higher in csDMARD-IR and bDMARD-IR cohorts.