Cytokines in rheumatoid arthritis: trials and tribulations

Biological agents that inhibit the activity of proinflammatory cytokines ar e being investigated for use in the treatment of rheumatoid arthritis, Thus far, two of these agents, both of which neutralize tumor necrosis factor a lpha (TNF-alpha), have received US Food and Drug Administration approval fo r the treatment of the disease, Etanercept is a bioengineered fusion protei n of the p75 soluble TNF receptor, and infliximab is a chimeric monoclonal antibody to TNF-alpha, Other agents that target proinflammatory cytokines a re also being developed. By allowing earlier treatment and better-tolerated long-term therapy, biologics might help slow or prevent disease progressio n and joint destruction.