Tocilizumab is a fully humanized monoclonal antibody against interleukin-6 receptors that was approved for the treatment of patients with rheumatoid arthritis (RA). Several lines of evidence, obtained both from conventional disease-modifying anti-rheumatic drugs (DMARDs) and tumor necrosis factor (TNF) inhibitors, have supported the concept of "window of opportunity" as showing that these therapies consistently work better in early disease as compared to established RA. This review addresses the question of whether a window of opportunity gained with conventional DMARDs and TNF inhibitors can also be achieved with tocilizumab. To this end, data regarding the use of tocilizumab in early RA patients are summarized. Currently available data suggest that the earlier the treatment with tocilizumab, the better the clinical outcome can be, which may have implications for various aspects of RA treatment strategies.
Keywords: early intervention; rheumatoid arthritis; tocilizumab.