Subcutaneous formulation of tocilizumab for treatment of rheumatoid arthritis.

Tocilizumab (TCZ) is a humanized monoclonal antibody against the IL-6 receptor that is indicated for the treatment of rheumatoid arthritis (RA), juvenile idiopathic arthritis and Castleman's disease. TCZ was developed as an intravenous (IV) formulation and approved for RA treatment in Japan (2008), the EU (2009) and the USA (2010). Recently, a subcutaneous (SC) formulation of TCZ was developed and approved for RA treatment. Efficacy and safety of TCZ-SC were reported through three randomized trials: MUSASHI, SUMMACTA and BREVACTA. Clinical efficacy and overall safety of TCZ-SC was comparable to that of TCZ-IV. However TCZ-SC, which is provided in a fixed dose, the efficacy was affected by patient weight. The frequencies of injection site reactions and anti-TCZ antibodies were increased with TCZ-SC compared with TCZ-IV, although differences were minimal and at a negligible level for daily clinical practice. This review highlights the potential of TCZ-SC in RA treatment.