Success of Tocilizumab in RA Patients With Remission Induction and Sustained Efficacy After Discontinuation

Inclusion Criteria: * Diagnosed with RA in accordance with the 1987 classification criteria of ACR * Aged 20 to 75 years inclusive at enrolment (within 2 weeks before starting treatment with the investigational drug) * Treated with MTX at ≥6 mg/week for at least 8 weeks immediately before enrolment * Rheumatoid arthritis of duration ≤10 years * DAS28-ESR ≥3.2 (within 2 weeks before starting treatment with the investigational drug) * Having received and thoroughly understood an adequate explanation about participation in the study, patients who have personally and voluntarily provided written informed consent Major exclusion criteria: * Patients who were Steinbrocker Class IV. * Patients who received leflunomide within 12 weeks, DMARDs other than MTX within 8 weeks , or tacrolimus within 4 weeks before the 1st TCZ infusion. * Patients who previously received biologic DMARDs including TCZ.