内科: オープンアクセス
オープンアクセス

概要

Is Methotrexate (MTX) Necessary in Combination Therapy with Tocilizumab and MTX for Rheumatoid Arthritis in Remission? Cohort Study Carried by the Michinoku Tocilizumab Study Group

Masayuki Miyata, Yasuhiko Hirabayashi, Yasuhiko Munakata, Yukitomo Urata, Koichi Saito, Hiroshi Okuno, Masaki Yoshida, Takao Koderai, Ryu Watanabei, Seiya Miyamoto, Tomonori Ishii, Shigeshi Nakazawa, Hiromitsu Takemori, Takanobu Ando, Takashi Kanno, Masataka Komagamine, Ichiro Kato, Yuichi Takahashi, Atsushi Komatsuda, Kojiro Endo, Chihiro Murai, Yuy

Objectives: To determine the necessity of methotrexate (MTX) in patients with rheumatoid arthritis (RA) achieving clinical remission treated by tocilizumab (TCZ) and MTX (TCZ+MTX).

Methods: A 3 year, multicenter, observational cohort study was performed. RA patients were treated by TCZ with or without MTX depending on the attending doctor’s decision. Of the patients treated with TCZ+MTX, the patients who discontinued MTX after achieving clinical remission (discontinued group: DISC) were compared with those who maintained the same dose of MTX after achieving clinical remission (maintained group: MAIN).

Results: The DISC and MAIN consisted of 33 patients and 37 patients, respectively. The mean DAS28-ESR was significantly lower in the DISC than in the MAIN at 3 months, 6 months and 9 months (3 months: 1.8 ± 0.8 and 2.4 ± 1.0, p=0.018, 6 months: 1.5 ± 0.7 and 2.2 ± 1.0, p=0.009 and 9 months: 1.4 ± 0.6 and 2.0 ± 1.0, p=0.008, respectively). The DAS28-ESR remission rate and Boolean remission rate were significantly higher in the DISC than in the MAIN (93.8% and 64.5%, respectively in the DAS28-RSR, p=0.04; 51.6% and 17.2%, respectively in the Boolean, p=0.005) at 6 months.

Conclusions: RA patients treated by the combination of TCZ and MTX who achieved deep remission (DAS28- ESR ≤ 1.98) at as early as 3 months could discontinue taking MTX.