ABSTRACT
Abstract Background Our aim was to compare the efficacy of rituximab, tocilizumab, and abatacept in individuals with rheumatoid arthritis (RA) refractory to treatments with MTX or TNFi agents. Methods We searched 6 databases until January 2023 for phase 2-4 RCTs evaluating patients with RA refractory to MTX or TNFi therapy treated with rituximab, abatacept, and tocilizumab (intervention arm) compared to controls. Study data were independently assessed by two investigators. The primary outcome was considered as achieving ACR70 response. Results The meta-analysis included 19 RCTs, with 7,835 patients and a mean study duration of 1.2 years. Hazard ratios for achieving an ACR70 response at six months were not different among the bDMARDs, however, we found high heterogeneity. Three factors showing a critical imbalance among the bDMARD classes were identified: baseline HAQ score, study duration, and frequency of TNFi treatment in control arm. Multivariate meta-regression adjusted to these three factors were conducted for the relative risk (RR) for ACR70. Thus, heterogeneity was attenuated (I2 = 24%) and the explanatory power of the model increased (R2 = 85%). In this model, rituximab did not modify the chance of achieving an ACR70 response compared to abatacept (RR = 1.773, 95%CI 0.113-10.21, p = 0.765). In contrast, abatacept was associated with RR = 2.217 (95%CI 1.554-3.161, p < 0.001) for ACR70 compared to tocilizumab. Conclusion We found high heterogeneity among studies comparing rituximab, abatacept, and tocilizumab. On multivariate metaregressions, if the conditions of the RCTs were similar, we estimate that abatacept could increase the chance of reaching an ACR70 response by 2.2-fold compared to tocilizumab. Key messages Abatacept could increase the chance of reaching an ACR70 response by 2.2-fold compared to tocilizumab.