Survival on treatment with second-line biologic therapy: a cohort study comparing cycling and swap strategies

Objective. The aim of this study was to evaluate the survival on treatment with second-line biologic therapy in RA patient non-responders to TNF inhibitors (TNFis) by comparing treatments with a second anti-TNF (cycling strategy) or with agents with a different mechanism of action (MoA; swap strategy). Methods. RA patients treated with biologics since 1999 who stopped a first-line TNFi and started a second-line biotherapy were included in this cohort study. After adjusting for propensity scores, drug retention rates were calculated using the Kaplan-Meier method. The log-rank test was used to compare survival curves and the Cox regression model was used to compare risk for discontinuation between the two groups. Results. Two hundred and one patients discontinued the first TNFi, switching to a second anti-TNF [n = 119 (59.2%)] or to abatacept [n = 26 (31.7%)], rituximab [n = 40 (48.8%)] or tocilizumab [n = 15 (18.3%)]. Drug survival was significantly higher in the swap group than in the cycling group (P < 0.0001). After adjustment for propensity scores, probability of treatment retention in the swap group was significantly higher (hazard ratio = 2.258, 95% CI 1.507, 3.385), even after stratification according to the reason for the first TNFi discontinuation (P = 0.005). No significant differences emerged when comparing the retention rates of different MoAs (P = 0.51) in the swap group. Conclusion. In the clinical practice setting, the best option for managing TNFi non-responders seems to be swapping to a different MoA, with no differences between abatacept, rituximab and tocilizumab, irrespective of the reason for first TNFi discontinuation.