Clinical outcome in patients with rheumatoid arthritis switched to tocilizumab after etanercept or infliximab failure

The present study retrospectively assessed the efficacy of tocilizumab in patients with rheumatoid arthritis (RA) who failed to respond to treatment with etanercept or infliximab. A retrospective study of 33 RA patients who did not respond to etanercept or infliximab was conducted. Responses of subjects switching from etanercept to tocilizumab (n = 17) were compared with those switching from infliximab to tocilizumab (n = 16). Treatment with disease-modifying antirheumatic drugs before the switch, especially methotrexate (MTX), was maintained. Disease activity was assessed by the Disease Activity Score 28-C Reactive Protein (DAS28-CRP), the Simplified Disease Activity Index (SDAI), and the Clinical Disease Activity Index (CDAI). Patients who switched from etanercept were significantly less likely to have used MTX and were significantly older than patients who switched from infliximab. In both groups, there was a significant reduction from baseline in DAS28-CRP, SDAI, and CDAI values at 24 weeks with no significant differences between groups. However, at week 52, DAS28-CRP, SDAI, and CDAI values in the group switched from etanercept were significantly worse than those in the group switched from infliximab. All patients switched from infliximab were using MTX. In the evaluation between patients who switched from etanercept monotherapy, etanercept plus MTX, and infliximab plus MTX, a significant improvement from baseline was seen in DAS28-CRP, SDAI, and CDAI for all patients at 24 weeks with no significant differences between groups. Disease activity was maintained at 52 weeks in the group that switched from etanercept plus MTX and infliximab plus MTX. However, the efficacy of tocilizumab was decreased in the group that switched from etanercept monotherapy. Switching from etanercept plus MTX or from infliximab plus MTX to tocilizumab plus MTX improved response to therapy, but switching from etanercept monotherapy to tocilizumab monotherapy did not improve response to therapy.