Clinical Pharmacology Study of MRA in Patient With Rheumatoid Arthritis (RA) With Renal Impairment

Inclusion criteria * Patients who are diagnosed with RA according to the 1987 ACR (American College of Rheumatology) classification criteria * Patients with RA at least 6 months prior to enrollment * Patients with a creatinine clearance not less than 10 mL/min but no higher than 80 mL/min Exclusion criteria * Patients with Class IV Steinbrocker functional impairment at enrollment * Patients who are undergoing dialysis * Patients who have been treated for the underlying disease with a biological agent, such as infliximab or etanercept, and have been receiving treatment with leflunomide, within 12 weeks before treatment with the investigational product