A Study of Duration of Maintained Efficacy in Rheumatoid Arthritis (RA) Patients Off Treatment With MRA(a Development Code of Tocilizumab, an Anti IL-6 Receptor Monoclonal Antibody.)

A Study to Investigate the Duration of Maintained Efficacy in Patients With Rheumatoid Arthritis Who Had Treated With MRA

A 52-week follow up study to investigate the duration of maintenance of efficacy in patients with RA and achieved low disease activity in clinical trials of MRA and stopped the treatment

Inclusion Criteria:

• Patients who achieved DAS28 of < 3.2 at the last observation and at least one time point among the two previous assessment time points in a previous studies.

Exclusion Criteria:

• Patients who receive DMARDs or immunosuppressants between the last observation in a previous studies and the first observation in this study