Effect of Biological Therapy for Psoriasis on the Development of Psoriatic Arthritis: A Population-Based Cohort Study

Background: Evidence comparing the impact of various biologics for psoriasis on the progression to psoriatic arthritis (PsA) is limited. We therefore assessed the risk of PsA associated with interleukin (IL)-23 inhibitor, IL-17 inhibitor, or IL-12/23 inhibitor use compared with tumor necrosis factor (TNF) inhibitor use among patients with psoriasis. Methods: This population-based cohort study used the nationwide claims database from South Korea (2007–2023). New users of IL or TNF inhibitors with psoriasis who did not have PsA or other inflammatory arthritis were categorized into each class of the IL inhibitors for comparison with TNF inhibitor users. The outcome measured was the development of incident PsA. We calculated multinomial overlap weights to balance predefined covariates. Hazard ratio (HR) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards models. Results: We identified 9499 patients with psoriasis (mean age 45.1 years; 33.6% female), of whom 3913 (41.2%), 2126 (22.4%), 2773 (28.8%), and 727 (7.7%) were exposed to IL-23 inhibitor, IL-17 inhibitor, IL-12/23 inhibitor, and TNF inhibitor, respectively. PsA developed in 281 (3.0%) patients during 23,275 person-years. The weighted HR for any IL inhibitors was 0.40 (95% CI 0.25–0.62), with specific HRs of 0.22 (95% CI 0.13–0.37), 0.47 (95% CI 0.28–0.80), and 0.46 (95% CI 0.29–0.74) for IL-23 inhibitor, IL-17 inhibitor, and IL-12/23 inhibitor, respectively. IL-23 inhibitors exhibited the greatest rate difference of − 2.61 (95% CI − 3.67 to − 1.55) cases of PsA per 100 person-years. Conclusions: The use of IL inhibitors, particularly IL-23 inhibitors, compared with TNF inhibitors, was associated with a lower risk of developing PsA.