Clinical and structural remission rates increased annually and radiographic progression was continuously inhibited during a 3-year administration of tocilizumab in patients with rheumatoid arthritis: A multi-center, prospective cohort study by the Michinoku Tocilizumab Study Group

Abstract

Objective: To evaluate the clinical and structural efficacy of tocilizumab (TCZ) during its long-term administration in patients with rheumatoid arthritis (RA).

Methods: In total, 693 patients with RA who started TCZ therapy were followed for 3 years. Clinical efficacy was evaluated by DAS28-ESR and Boolean remission rates in 544 patients. Joint damage was assessed by calculating the modified total Sharp score (mTSS) in 50 patients.

Results: When the reason for discontinuation was limited to inadequate response or adverse events, the 1-, 2-, and 3-year continuation rates were 84.0%, 76.8%, and 72.2%, respectively. The mean DAS28-ESR was initially 5.1 and decreased to 2.5 at 6 months and to 2.2 at 36 months. The Boolean remission rate was initially 0.9% and increased to 21.7% at 6 months and to 32.2% at 36 months. The structural remission rates (ΔmTSS/year ≤ 0.5) were 68.8%, 78.6%, and 88.9% within the first, second, and third years, respectively. The structural remission rate at 3 years (ΔmTSS ≤ 1.5) was 66.0%, and earlier achievement of swollen joint count (SJC) of 1 or less resulted in better outcomes.

Conclusions: TCZ was highly efficacious, and bone destruction was strongly prevented. SJC was an easy-to-use indicator of joint destruction.

Keywords:

• Joint destruction
• Long-term administration
• Real clinical practice
• Rheumatoid arthritis
• Tocilizumab

Acknowledgments

The authors thank the other members of the MTSG who endorsed this project: Dr. Naohiko Gunji, Dr. Hideo Harigae, Dr. Satoshi Hoshi, Dr. Ryo Ichinohasama, Dr. Yoh Ishiguro, Dr. Eiji Itoi, Dr. Nobuki Maki, Dr. Takatomo Moro, Dr. Hiromasa Ohira, Dr. Naohisa Ouchi, Dr. Yuta Oyama, Dr. Akira Rikimaru, Dr. Souichi Saito, Dr. Akiko Sasaki, Dr. Takeshi Sasaki, Dr. Akira Sekiguchi, Dr. Tadashi Shimamura, Dr. Mikio Suzuki, Dr. Yuji Wakai, and Dr. Seiji Yamaya. The authors would also like to thank the Clinical Research, Innovation and Education Center at Tohoku University Hospital for data analysis, and thank Editage (www.editage.jp) for English language editing.

Conflict of interest

YH has received consulting fees, speaking fees, and/or honoraria from Asahi Kasei, Bristol-Myers Squibb (BMS), Chugai, Eisai, Janssen, Kyowa Hakko Kirin, Mitsubishi Tanabe, and Takeda. MM has received speaking fees and/or honoraria from AbbVie, Chugai, BMS, Takeda, and Janssen. YU has received speaking fees and/or honoraria from Chugai, Ono, Pfizer, Mitsubishi Tanabe, and Sekisui. MY has received speaking fees and/or honoraria from Astellas, BMS, Pfizer, and Chugai. SM has received speaking fees from Chugai, Takeda, and Mitsubishi Tanabe. TI has received speaking fees from Chugai, Astellas, Ono, AbbVie, Pfizer, Teijin, Janssen, and Mitsubishi Tanabe. SN has received speaking fees and/or honoraria from Astellas, Janssen, and Mitsubishi Tanabe. HT has received speaking fees and/or honoraria from Mitsubishi Tanabe, Astellas, Ono, AbbVie, Actelion, Takeda, Eisai, Daiichi Sankyo, Teijin, Chugai, Asahi Kasei, GlaxoSmithkline (GSK), and Kissei. TA has received honoraria from Astellas. MK has received speaking fees and/or honoraria from Chugai, Pfizer, Astellas, and Eisai. YT has received speaking fees from Chugai, Astellas, and Janssen. AK has received speaking fees and/or honoraria from Chugai, Novartis, Torii, Eisai, Kyowa Hakko Kirin, Santen, Teijin, Otsuka, Baxtar, Actelion, Sumitomo Dainippon, Takeda, BMS, AbbVie, Astellas, Kissei, Kowa, Mitsubishi Tanabe, Japan Blood Products Organization, Asahi Kasei, Daiichi Sankyo, and Taisho Toyoma. KE has received speaking fees from Chugai, Astellas, BMS, and Mitsubishi Tanabe. CM has received speaking fees and/or honoraria from Chugai, Pfizer, BMS, Eisai, and Astellas. YT has received speaking fees from Chugai, Astellas, AbbVie, Mitsubishi Tanabe, Takeda, and Ono. YS has received speaking fees from Pfizer. KI has received speaking fees and/or honoraria from Chugai, Kyowa Hakko Kirin, Otsuka, and Kissei. TK has received honoraria from Chugai, Pfizer, Astellas, Eisai, and Mitsubishi Tanabe. NC has received speaking fees and/or honoraria from Astellas, Eisai, Takeda, and Mitsubishi Tanabe. KO has received speaking fees and/or honoraria from Astellas and Lilly. HS has received speaking fees and/or honoraria from BMS, Chugai, AbbVie, and Kyowa Hakko Kirin. ST has received speaking fees and/or honoraria from Kyowa Hakko Kirin, Daiichi Sankyo, and Torii. ES has received speaking fees and/or honoraria from Chugai, Janssen, AbbVie, Mitsubishi Tanabe, Astellas, and Pfizer. MT has received speaking fees and/or honoraria from Chugai, Astellas, Takeda, Biomet, Zimmer, Pfizer, Daiichi Sankyo, Asahi Kasei, and Hisamitsu. HW has received speaking fees and/or honoraria from AbbVie, Actelion, Astellas, Astrazeneca, Ono, and Pfizer. KM has received speaking fees from Pfizer, Mitsubishi Tanabe, and BMS. YM has received speaking fees from Mitsubishi Tanabe, Astellas, Chugai, and Daiichi Sankyo. TK has received consulting fees and speaking fees from Chugai, Pfizer, Astellas, AbbVie, BMS, and Mitsubishi Tanabe. Other authors declared no conflicts of interest.

This study was supported by a grant from Ichinohasama Memorial READ Blood Academy and by a clinical research fund from Hikarigaoka Spellman Hospital. Data collection was partially supported by Chugai Pharmaceutical Company Limited during PMS.