Interleukin-6 (IL-6) is a pleiotropic cytokine involved in the pathogenesis of rheumatoid arthritis (RA) and other autoimmune diseases. IL-6 regulates immune response and in ammation. Tocilizumab, a humanized anti-IL-6 receptor monoclonal antibody, binds both soluble and membrane - expressed IL-6R, inhibiting IL-6-mediated biological activity. In patients with moderate to severe active RA responding inadequately or who are intolerant to disease-modifying anti-rheumatic drugs (DMARD) or tumor necrosis factor (TNF) antagonists, tocilizumab,administered either as monotherapy or in combination with conventional DMARDs is e ective and generally safe option for the treatment of rheumatoid arthritis.

Keywords: Tocilizumab, interleukin-6, rheumatoid arthritis.