[Abatacept].

Abatacept (ABT) is a recombinant fusion protein comprising the extracellular domain of human CTLA4, which inhibits the activation of T cells. Several clinical trials have provided evidence of efficacy and safety of ABT in the patients with rheumatoid athritis (RA) with various clinical characteristics such as MTX inadequate responders (IR), TNF inhibitor-IR. Moreover, indirect comparison of ABT to other biologics reported in Cochrane review revealed that ABT has better safety profile in serious adverse events and serious infection Thus the features of ABT in the treatment of RA have gradually become apparent and knowledge of these features is helpful for better use of biologics. In this review we will discuss the efficacy and safety of ABT in the management of RA.