[Diagnosis and treatment of rheumatoid arthritis:toward the best practice. Best practice in the use of T cell co-stimulatory inhibitor for patients with rheumatoid arthritis.].

CTLA4 abolishes interaction between CD28 on T cells and B7 molecules on antigen presenting cells. CTLA4-Ig, abatacept(ABT)was developed as a drug with multipotent inhibitor against activated T/B cells, monocytes, dendritic cells, macrophages and osteoclast progenitors expressing B7 molecules. In phase Ⅲ RCTs, clinical effects of ABT have been established in MTX-naive, MTX-IR and TNF inhibitor-IR patients with RA. Moreover, in head-to head comparison with representative TNF inhibitors, ABT exerted compatible clinical effect. In clinical practice, ABT is recognized as a biological DMARD with good safety profile. Reduction or withdrawal of ABT is also proposed in patients who achieved remission under treatment with ABT+MTX. In conclusion, ABT can be included in the treatment strategy of RA with wide clinical variance.