Background Although anti-TNF blocker prevents joint destruction and makes a role of being drastic change on rheumatoid arthritis treatment, patients who are poor response against the treatment with anti-TNF blocker also exists. One of major problem of Infliximab (IFX) is loss of efficacy. Doing treatment to maintain its efficacy by dose escalation of IFX (DE group) and shortening intervals of IFX (SI group) were performed. But the superiority of both methods remains unclear.
Objectives To investigate the continuity and effectiveness of both groups using multi-center registry for the treatment of RA with biologics in Japan (Tsurumai Biologics Communications registry;TBCR).
Methods 603 cases who are treated with IFX from 2072 registrated cases of TBCR until 2011. 136 (22.6%) cases were treated with shortening intervals of IFX to 7 weeks or less, while 115 cases (19.1%) were treated with dose escalation of IFX to add 100mg or over. Baseline characteristics were summarized in Table 1. Drug survival of both therapies was examined using Kaplan-Meier survival analysis.
Results In SI group, 33 cases (24.3%) discontinued IFX therapy because of loss of efficacy, 15 cases (11.0%) stopped IFX infusion because of adverse events (AEs). In DE group, 36 cases (31.3%) discontinued IFX therapy because of loss of efficacy, 10 cases (8.7%) stopped IFX infusion because of AEs. The continuation of SI group was significantly higher than that of DE group by the Kaplan-Meier method ((Log-rank test; p=0.042) Fig. 1). Furthermore, we divided timing of escalation of therapy is one year over/less from starting IFX. Patients with shortening intervals after more than 1 year had the highest survival rate of all of groups ((Log-rank test; p=0.010) Fig. 2). Drug survival of both groups was significantly higher compared the all of IFX use group in TBCR (n=603) ((Log-rank test; p<0.001) Fig. 3).
Conclusions In occurring loss of efficacy of IFX, we should remember the effectiveness of not only dose escalation of IFX but also shortening intervals of IFX, considering the maintenance of drug trough.
Disclosure of Interest K. Funahashi: None Declared, T. Kojima Speakers Bureau: Abbott Japan, Chugai Pharmaceutical, Daiichi Sankyo Pharmaceutical, Eisai, Mitsubishi Tanabe Pharma, Pfizer Japan, Takeda Pharmaceutical, N. Takahashi: None Declared, D. Kato: None Declared, H. Matsubara: None Declared, Y. Hattori: None Declared, N. Ishiguro Speakers Bureau: Abbott Japan, Chugai Pharmaceutical, Daiichi Sankyo Pharmaceutical, Eisai, Mitsubishi Tanabe Pharma, Pfizer Japan, Takeda Pharmaceutical