This open-label study will evaluate the long-term safety and efficacy of RoActemra/Actemra (tocilizumab) in combination with disease modifying anti-rheumatic drugs (DMARDs) in patients with moderate to severe rheumatoid arthritis. Patients who successfully completed studies WA17823 and WA18696 in South Africa are eligible to participate in this study. Patients will be allowed DMARDs according to the treatment they received in the previous studies. Patients will receive 8 mg/kg RoActemra/Actemra intravenously every 4 weeks. The anticipated time on study treatment is 104 weeks.