[The role of interleukin-6 in rheumatoid arthritis]

Cytokines such as TNF-alpha and IL-1beta play key roles in driving the inflammation and synovial cell proliferation that characterize rheumatoid arthritis (RA) joint destruction. It is, therefore, not surprising that therapies for RA have targeted these cytokines. While blockade of TNF-alpha or IL-1beta has been efficacious for many patients with RA, adequacy and maintenance of response are not universal, and increased risk of adverse events such as infections and malignancy remain a concern. Therefore, new targets in the treatment of RA continue to be examined. As interleukin-6 (IL-6) has been implicated in the pathogenesis of RA, blockade of its activity is of both scientific and clinical interest. Tocilizumab has been assessed in a number of studies in recent years, mainly in patients with rheumatoid arthritis. Data from randomized controlled clinical trials demonstrate the effectiveness of tocilizumab in improving the signs and symptoms of RA. In addition, it appears that such inhibition of IL-6 can have positive effects on functional status, an important outcome for RA patients. Finally, data suggest that treatment with this agent may also inhibit the progression of disease as assessed radiographically. Data from recent studies will help to refine the ultimate use of this novel approach to treatment, and help clinicians to optimize therapy using this approach.