Background Tocilizumab (TCZ) is the first humanised monoclonal antibody that targets and inhibits the human interleukin-6 receptor. The ACT-RAY study proved the clinical efficacy and safety of adding TCZ to MTX versus switching from MTX to TCZ monotherapy in biologic-naïve adult patients with moderate to severe active rheumatoid arthritis (RA). . But the clinical long term outcome is not clear.
Objectives To evaluate the continuity and effectiveness of TCZ with/without MTX by using multi-center registry for the treatment of RA with biologics in Japan (Tsurumai Biologics Communication Registry; TBCR) .
Methods 302 RA patients treated with TCZ for at least 24 months in Nagoya University Hospital and 12 affiliated institutes (TBCR Study Group) were enrolled in this study.155 cases treated with MTX at the baseline (MTX+ group),147 case did not take MTX at the baseline (MTX- group). Difference in baseline characteristics was summarized in Table 1. Drug retention rate of both groups was examined using Kaplan-Meier survival analysis. DAS28ESR was compared between these two groups by unpaired t- test at 0, 6, 12, 24 months. The last observation carried forward (LOCF) method was used in each analysis.
Results In MTX+ group, 12 cases (7.7%) discontinued TCZ therapy because of inadequate response (IR), 12 cases (7.7%) stopped TCZ infusion because of adverse events (AEs), 8 (5.1%) cases stopped due to other reasons. In MTX- group, 13 cases (8.8%) discontinued TCZ therapy because of IR, 18 cases (12.2%) stopped TCZ infusion because of AEs, 11 (7.5%) cases stopped due to other reasons. DAS28ESR of MTX+ group at 0, 6, 12, 24 months was 5.4, 2.9, 2.7, and 2.7, respectively. That of MTX- group was 5.8, 3.3, 3.3, and 3.4, respectively. Although disease activity based on DAS28ESR was not significantly different between two groups at 0, 6 months, it is significantly different at 12, 24 months (p<0.01) (Fig. 1). The continuation of both groups was not significantly different by the Kaplan-Meier method ((Log-rank test; p=0.70) (Fig. 2). The proportion of low disease activity and remission based on DAS28ESR was 65.0% in MTX+ group and 41.3% in MTX- group at 24 months (Fig. 3).
Conclusions Although the continuity of TCZ therapy is not significantly different with/without MTX, the clinical response of TCZ therapy is significantly different with/without MTX in 2 years results. Considering the maintenance treatment with TCZ for RA, we had better treat TCZ in combination with MTX.
Ann Rheum Dis. 2013 Jan;72(1):43-50.
Mod Rheumatol. 2012 Jun;22(3):339-45.
Disclosure of Interest K. Funahashi: None declared, T. Kojima Speakers bureau: Mitsubishi Tanabe Pharma Corporation, Takeda Pharma Corporation, Eisai Pharma Corporation, Chugai Pharma Corporation,Abbott, Bristol-Myers Squibb and Pfizer, N. Takahashi: None declared, M. Hanabayashi: None declared, S. Hirabara: None declared, S. Asai: None declared, Y. Yoshioka: None declared, Y. Yabe: None declared, N. Ishiguro Speakers bureau: Mitsubishi Tanabe Pharma Corporation, Takeda Pharma Corporation, Eisai Pharma Corporation, Chugai Pharma Corporation,Abbott, Bristol-Myers Squibb and Pfizer