A multicenter, open-label, long-term study of three-year infliximab administration in Japanese patients with ankylosing spondylitis

Abstract

Objective: To investigate the efficacy, safety, and pharmacokinetics of infliximab (IFX) in Japanese patients with active ankylosing spondylitis (AS).

Methods: In this multicenter open-label study, IFX was infused at 5 mg/kg to 33 Japanese patients with active AS using or intolerable to non-steroidal anti-inflammatory drugs (NSAIDs) at Weeks 0, 2, and 6, and then every six weeks for approximately three years (mean: 149.5 weeks).

Results: Assessment in Ankylosing Spondylitis (ASAS) 20 response at Week 24 (primary endpoint) was 97.0% (32/33) and was thereafter maintained at approximately 90% over the three-year study period. Improvements in range of motion, physical function, inflammatory parameters, and quality of life (QOL) were all maintained throughout the three-year study period. A serum IFX level of ≥5 μg/mL was maintained with six-week infusion intervals, and only two patients (6.1%) developed antibodies to IFX. Specific adverse events in AS patients were not observed.

Conclusion: These findings suggest that a 5 mg/kg administration of IFX at six-week intervals to Japanese patients with active AS is safe, effective and provides long-term therapeutic benefits.

Keywords:

• Infliximab
• Ankylosing spondylitis
• Anti-TNFα monoclonal antibody
• Japan
• Clinical trial

Acknowledgments

The authors would like to dedicate this paper to the last Kanji Shichikawa, emeritus professor of Shiga University of Medical Sciences and chairman of the Japan Spondyloarthritis Society, who led and educated us for more than 50 years, participated in this study, and passed away in April 2014. The authors also would like to thank the following investigators who participated in the present study: Manabu Itoh (National Hospital Organization Hokkaido Medical Center); Tsutomu Takeuchi (School of Medicine, Keio University); Nobuyuki Miyasaka (Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University); Yoshinari Takasaki and Hisashi Inoue (Juntendo University School of Medicine); Masao Yukioka and Norikazu Murata (Yukioka Hospital); Kazuhiro Hatta (Tenri Hospital); Hiroaki Dobashi (Graduate School of Medicine, Kagawa University); Yoshiya Tanaka (University of Occupational and Environmental Health, Japan); Yasuharu Nakashima (Graduate School of Medical Sciences, Kyushu University).

Conflict of interest

SK has received research grant support from Chugai Pharmaceutical, and lecture fees from AbbVie GK, Actelion Pharmaceuticals Japan, Astellas Pharma, Bristol-Myers KK, Chugai Pharmaceutical, Eisai, Janssen Phramaceutical KK, Nippon Shinyaku, Mitsubishi Tanabe Pharma, Pfizer Japan, Takeda Pharmaceutical, Teijin Pharma, UCB Japan, and Zenyaku Kogyo; TY is an employee of Mitsubishi Tanabe Pharma.

Mitsubishi Tanabe Pharma Corporation sponsored this clinical trial and was responsible for the collection and analysis of data. The authors and the sponsor were involved with study design and interpretation of data.