Cycling versus swapping strategies in psoriatic arthritis: results from the rheumatic diseases Portuguese register

Objective: To compare the 2-year retention rate between a second tumor necrosis factor alpha inhibitor (TNFi) and secukinumab (SEK) or ustekinumab (UST), in Psoriatic Arthritis (PsA) patients with previous inadequate response to their first TNFi. Methods: Prospective longitudinal cohort study with a follow-up period of 2 years using the Nationwide Portuguese Reuma.pt database. Patients with a clinical diagnosis of PsA who also fulfill the CASPAR classification criteria, with previous treatment failure to a first-line TNFi and having started a second biotechnological drug (TNFi, SEK or UST) were included. The Cycling group was defined as switching from a first TNFi to a second TNFi, and the Swapping group as switching from a first TNFi to SEK or UST. Sociodemographic data, disease characteristics, disease activity scores and physical function at baseline and after 6, 12 and 24 months were recorded. Cox-proportional hazards regression was used to compare retention rates between Cycling and Swapping groups. To obtain a predictor model of 2-year discontinuation, a multivariable Cox regression model was performed. Results: In total, 439 patients were included, 58% were female, with a mean age (standard deviation) of 49 (12) years. Globally, 75.6% initiated a second TNFi (Cycling group), and 24.4% started SEK/UST (Swapping group). The retention rates after 6, 12 and 24 months were 72%/66%/59% in the Cycling group; and 77%/66%/59% in the Swapping group. There were no significant differences in retention rates between both strategies (HR: 1.06, 95% CI 0.72-1.16). After 2 years of follow-up, 34.4% of patients discontinued their second biologic, mainly due to inefficacy (72.8%), with no differences found between groups. Baseline treatment with glucocorticoids was the only predictor of discontinuation after 2 years of follow-up (HR:1.668, 95% CI 1.154-2.409). Conclusions: After failure of a first TNF inhibitor, Cycling and Swapping strategies result in similar retention rates suggesting that both are acceptable in the management of patients with psoriatic arthritis.