Biological DMARDs have markedly changed the management and outcome of rheumatoid arthritis. Most international guidelines recommend the use of biological DMARDs in combination with MTX or other synthetic DMARDs (sDMARDs) (where MTX is not tolerated or contraindicated), based primarily on the observation that MTX enhances the efficacy of TNF antagonists in both clinical trials and observational studies.This study examined the effectiveness of tocilizumab (TCZ), an anti-IL-6 monoclonal antibody, ...