Persistence, switching, and discontinuation patterns of b/tsDMARDs in patients with rheumatoid arthritis: a single-center retrospective cohort study from Saudi Arabia

Saad A. Aldosari, Areej Alkhaleel, Mukhtar Alomar, Laila AlGhalawin, Ahmad Alamer

Objective To characterize real-world treatment patterns, including persistence, switching, and discontinuation, of biologic and targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs) in patients with rheumatoid arthritis (RA) in Saudi Arabia. Methods This retrospective cohort study was conducted at Dammam Medical Complex in Saudi Arabia. Adult RA patients naïve to b/tsDMARDs who initiated therapy between January 1, 2013, and January 31, 2023, were included. Treatment patterns were summarized using descriptive statistics. Drug survival was assessed with Kaplan–Meier curves and Cox proportional hazards models. Results Among 175 eligible patients, first-line therapy was a tumor necrosis factor inhibitor (TNFI) in 109 (62.3%), a non-TNFI in 47 (26.9%), and tofacitinib in 19 (10.9%). Estimated drug survival probabilities at 5 years were 0.47 (95% CI: 0.37–0.59) for TNFIs, 0.51 (95% CI: 0.38–0.68) for non-TNFIs, and 0.68 (95% CI: 0.48–0.97) for tofacitinib. At 10 years, survival was 0.33 (95% CI: 0.23–0.48) for TNFIs and 0.27 (95% CI: 0.16–0.45) for non-TNFIs. Kaplan–Meier analysis showed no significant difference across classes (log-rank p = 0.68). Adjusted hazard ratios for switching or discontinuation (reference: TNFIs) were 1.10 (95% CI: 0.69–1.74, p = 0.68) for non-TNFIs and 0.68 (95% CI: 0.27–1.72, p = 0.42) for tofacitinib. The primary reason for switching was lack/loss of efficacy, while pregnancy and non-adherence were the most frequent causes of discontinuation. Conclusion Tumor necrosis factor inhibitors were the most commonly initiated first-line b/tsDMARD in this Saudi cohort. Persistence appeared comparable across classes, although the small sample size limits definitive conclusions. These findings provide initial real-world insights into the utilization of advanced RA therapies at a single tertiary center in Saudi Arabia.