1. Discovery Laboratories and Research Laboratories, Toyama Chemical Co., Ltd., 4-1 Shimookui 2-chome, Toyama 930-8508, Japan, Department of Rheumatology, Faculty of Health Science, Kobe University School of Medicine, 7-10-2 Tomogaoka, Suma-ku, Kobe 654-0142, Japan, Rheumatic Disease Division, Kobe University Hospital, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan, and School of Pharmaceutical Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan