Rheumatoid arthritis is an immunologically mediated inflammation of joints of unknown aetiology and often leads to disability. This inflammatory process may also involve extra-articular connective tissue. New therapeutic approaches have been made by inhibition of proinflammatory cytokines. Interleukin-1 (IL-1) is regarded as one of the most important mediators in the development of synovialitis. In this article, anakinra (Kineret), the first direct antagonist to IL-1, is discussed, in particular the efficacy and safety data from clinical trials. More than 10,000 patients have been treated with anakinra with significant improvement of inflammation and pain; the rate of radiologically visible progressive joint damage was significantly reduced. Among the adverse events, injection site reactions were most frequent, followed by a mild increase in infections. No activation of tuberculosis, as in tumour necrosis factor-alpha antagonist administration, has so far been reported.