Biological agents in rheumatoid arthritis.

Rheumatoid arthritis (RA) is the commonest inflammatory joint disease with considerable morbidity and mortality. Conventional disease-modifying antirheumatic drugs like methotrexate form the cornerstone of therapy. However, they have several limitations in terms of slow onset of action, adverse effects and modest remission and retention rates. Several cytokines are involved in the pathogenesis of RA. Biological agents that specifically inhibit the effects of tumour necrosis factor-a (TNF-a) or Interleukin-1 (IL-1) represent a major advancement in the treatment of RA. By targeting molecules that are directly involved in the pathogenesis of RA, these therapies are proving to be efficacious, highly specific and better tolerated than standard therapies. The use of these agents needs to be monitored carefully for possible side-effects, including the development of infections. Additional anti-cytokine agents for the treatment of RA are under further development.