OBJECTIVES: To compare tolerability and effectiveness of two different classes of biological Disease-Modifying Anti-Rheumatic Drugs (bDMARDs; interleukin (IL)-17- and IL-23(p19) inhibitors) relative to tumour necrosis factor inhibitors (TNFi) regarding the drug survival rates and treatment outcomes in patients with psoriatic arthritis (PsA).

METHODS: We emulated a target trial on comparative effectiveness using observational data from a prospective cohort study based on the Parker Institute's PsA cohort - the PIPA cohort. All patients underwent interview and clinical examination programme at baseline and at follow-up visits at four and twelve months. The primary endpoint, drug survival, was assessed up to 12 months from baseline. We estimated hazard ratios from proportional hazards model and used propensity score adjustment in an attempt to deconfound and emulate a random treatment assignment.

RESULTS: We included a total of 109 patients in the intention-to-monitor population at baseline initiating either TNFi (75 patients), IL17i (26 patients), or IL23(19)i (8 patients). Hazard ratios in the propensity adjusted model comparing IL-17i and IL-23(p19)i to TNFi were 1.36 (95% CI 0.59-3.14) and 0.56 (95% CI 0.10-3.24), respectively. TNFi and IL-17i had comparable effects regarding response rates and changes in clinical outcomes after 12 months, whereas IL-23(p19)i tended to perform better overall.

CONCLUSION: No decisive differences between drugs were observed at group level regarding drug survival and clinical outcomes after 12 months. TNFi, IL-17i, and IL-23(p19)i may all be considered equally effective in the treatment of patients with PsA, advocating for investigating more in personalised treatment strategies.