Background Efficacy and safety of biologic agents against refractory rheumatoid arthritis (RA) patients have been proved, however expensive cost is still a serious problem. Biologic free study about infliximab (RRR study) and adalimumab (HONOR study) were reported, but study about tocilizumab (TCZ) is none.

Objectives To investigate the maintenance ratio of biologic free, low disease activity (LDA), remission (REM) after discontinuation of TCZ in RA patients who had achieved REM

Methods One hundred and fifteen RA patients have been treated by TCZ in our institution after 2008 Jury. Among them, patients, who had achieved DAS-REM (DAS28ESR<2.6) by TCZ treatment and maintained DAS-REM over six months, and who discontinued TCZ by patients’ hope, were selected retrospectively. The ratio of biologic free, LDA, REM after discontinuation of TCZ were calculated by Kaplan Meier method. Related factor between the patients’ group who were flared arthritis and the patients’ group who could maintain disease activity were analyzed by logistic regression test.

Results Ten patients discontinued TCZ after remission by patients’ hope. All patients were bio-naïve patients and TCZ was used as first-bio. Average age was 53(25-69), average disease duration were 4.3 years (0.9-15.5), and average DAS28ESR was 1.5(0.5-1.8) at the point of TCZ discontinuation. Average duration of TCZ treatment was 86.2 weeks. Methotrexate user was 8 patients (4-10mg/wk) and predonisolone user was 3 patients (1-5mg/day). Arthritis flared to four patients over LDA at 15, 18, 22, 84 weeks after TCZ discontinuation respectively. Two patients restarted TCZ at 31 weeks, and 49 weeks after discontinuation of TCZ and clinical REM could be achieved soon, while another two patients did not restart TCZ. The maintenance ratio of biologic free was 100% (24wk), 53.3% (52wk). The maintenance ratio of LDA, and REM was 85.7%, 67.5% (24wk), and 45.7%, 33.8% (52wk) respectively. Significant related factor between flare group and maintenance group was not recognized.

Conclusions The maintenance ratio of LDA and REM after discontinuation of TCZ was low compared with previously reported biologic free study of TNF-inhibitor^{1) 2)}. This study was retrospective and number was small, further investigation will be needed.

1. Tanaka Y et al. Discontinuation of infliximab after attaining low disease activity in patients with rheumatoid arthritis: RRR (remission induction by Remicade in RA) study. Ann Rheum Dis. 69: 1286-1291, 2010

2. Tanaka Y. Intensive treatment and treatment holiday of TNF-inhibitors in rheumatoid arthritis. Curr Opin Rheumatol. 24: 319-326, 2012

Disclosure of Interest None Declared