Background The inhibition of radiographic progression is one of the important therapeutic goals in patients with rheumatoid arthritis (RA). Tocilizumab (TCZ) is a humanized anti-human IL-6 receptor antibody and it has been reported that it effectively inhibits radiographic progression over 1 year. However, there are few reports about efficacy of longer term administration.
Objectives The aim of this study is to assess the long-term efficacy of treatment with TCZ on radiographic progression in patients with RA under routine clinical practice.
Methods The Michinoku Tocilizumab Study Group comprises 34 institutions in the Northeast region of Japan. RA patients who received 8 mg/kg TCZ every 4 weeks were registered between June 2008 and December 2010 . Among them, the clinical and structural outcomes were evaluated in 130 patients who passed over 1 year including 50 patients who passed over 3 years.
Results At baseline, the mean age of 130 (50) patients was 59.7 (58.0) years, the mean disease duration was 10.8 (10.9) years, the mean DAS28-ESR was 4.8 (4.8), and 37.7 (36.0) % of patients were taking concomitant MTX. At one year, the mean change from baseline in van der Heijde-modified total Sharp score (mTSS) was 0.79 (0.57), and the structural remission rate (ΔmTSS≤0.5) was 69.2 (68.6) %. Neither disease duration nor concomitant MTX affected the structural remission rate at one year. The structural remission rate for 3 years (ΔmTSS≤1.5) was 66.0%, however, the mean change from 1 to 2 years in mTSS was 0.10, and that from 2 to 3 years was 0.02. Consistent with the yearly progression, the structural remission rate from 1 to 2 years was 78.6%, and that from 2 to 3 years was 88.9%, indicating that TCZ strongly and continuously inhibited radiographic progression.
Conclusions Long-term administration of TCZ increased the structural remission rate year by year and continuously inhibited structural joint damage in RA patients under routine clinical practice.
Hirabayashi Y, Ishii T, and the Michinoku Tocilizumab Study Group. The DAS28-ESR cutoff value necessary to achieve remission under the new Boolean-based remission criteria in patients receiving tocilizumab. Clin Rheumatol. DOI 10.1007/s10067-012-2103-4.
Disclosure of Interest R. Watanabe: None Declared, H. Okuno: None Declared, T. Ishii Speakers bureau: Chugai Pharma, H. Harigae Grant/research support from: Chugai Pharma, Y. Hirabayashi Speakers bureau: Chugai Pharma