Comparison of the clinical effectiveness of tumour necrosis factor inhibitors and abatacept after insufficient response to tocilizumab in patients with rheumatoid arthritis

The aim of this study is to compare the clinical effectiveness of tumour necrosis factor inhibitors (TNFi) and abatacept (ABT) after insufficient response to tocilizumab (TCZ) in patients with rheumatoid arthritis (RA). Among 527 RA patients treated with TCZ, 63 patients were enrolled who switched TCZ to alternative biologic agents because of moderate or high disease activity assessed by the Clinical Disease Activity Index (CDAI). They were divided into two groups, TNF inhibitors (TNFi) or abatacept (ABT), and compared for clinical effectiveness and adverse events at week 24. Forty-two were switched to TNFi, and 21 to ABT. TNFi included 19 infliximab, 3 adalimumab, 8 etanercept, 9 golimumab, and 3 certolizumab-pegol. Baseline characteristics at the switch were comparable except for the concomitant methotrexate use (TNFi 71.4 vs ABT 28.6 %, P = 0.003). The proportion of patients achieving CDAI ≤ 10 (remission or low disease activity) at week 24 was significantly higher in TNFi than ABT (64.3 vs 23.8 %, P = 0.003), and the values of the CDAI at week 24 was significantly better in TNFi than ABT (mean, 11.8 vs 16.4, P = 0.021) although the drug retention rate was not different between the two groups (73.8 vs 71.4 %, P = 0.803). No serious adverse event was observed in both groups. TNFi may be more effective than ABT to achieve clinical remission or low disease activity after insufficient response to TCZ in patients with RA, although drug retention rate and safety are comparable.