Background Tocilizumab, a humanized anti-interleukin-6 receptor monoclonal antibody, was approved in 2008 for use in clinical practice in Japan. The efficacy of tocilizumab in treating rheumatoid arthritis (RA) has been demonstrated in several clinical trials as well as in clinical practice. Given the high efficacy and safety, few patients switch from tocilizumab to other drugs, and limited studies have been reported in this regard. Controversy exists as to whether tumor necrosis factor inhibitors (TNFi) or abatacept should be selected when switching from tocilizumab.
Objectives The aim of this study was to compare the clinical efficacy of two classes of biologics, TNFi and abatacept, after switching from tocilizumab therapy.
Methods We performed a retrospective multicenter study of 40 RA patients who underwent 52-week biologic therapy after switching from tocilizumab therapy (Tsurumai Biologic Communication Registry). Patients were divided into two groups based on the biologic they switched to: TNFi (n=18) and abatacept (n=22). Changes in clinical parameters were examined at 0, 24, and 52 weeks after the switch: tender joint count (TJC) and swollen joint count (SJC) on 28 joints, general health on a visual analog scale (GH-VAS), and serum C-reactive protein (CRP) levels. Disease activity was evaluated at each time point using the 28-joint disease activity score with CRP (DAS28-CRP), as well as the clinical disease activity index (CDAI), which included data from the above-mentioned disease parameters.
Results Patients at baseline had a mean age of 60.3 years, mean disease duration of 12.1 years, and mean DAS28-CRP of 5.1. There was no significant difference between the two classes of drugs at baseline, except in disease durations and oral steroid use (%). Retention rates for TNFi and abatacept treatment at 52 weeks were 78.6% and 80.1%, respectively (Figure 1). Discontinuation due to all unfavorable causes did not significantly differ between the two in hazard ratio-based evaluations (Table 1). DAS28-CRP levels were lower with TNFi compared to abatacept at 24 weeks (TNFi, 3.52; abatacept, 4.12, p=0.033), but no difference was found at 52 weeks (TNFi, 3.55; abatacept, 3.94, p=0.135) (Figure 2). Percentages of subsequent low disease activity of CDAI for TNFi and abatacept were 46.2%, and 22.2%, respectively.
Conclusions This study is the first to compare the clinical efficacy of two different classes of biologics (TNFi and abatacept) after switching from tocilizumab using a multicenter registry system. Our results show that TNFi and abatacept are both effective, with no significant differences. When switching from tocilizumab, the characteristics of each drug should be considered to make an appropriate choice for each patient.
Nishimoto N, et al. Ann Rheum Dis. 2009;68(10):1580-4.
Kojima T, et al. Mod Rheumatol. 2012;22(3):370-5.
Yamanaka H, et al. Mod Rheumatol. 2011;21(2):122-33.
Disclosure of Interest None declared