Abatacept

Abatacept, sold under the brand name Orencia, is a medication used to treat autoimmune diseases like rheumatoid arthritis, by interfering with the immune activity of T cells.[1][3] It is a modified antibody.[1][3] Abatacept is a fusion protein composed of the Fc region of the immunoglobulin IgG1 fused to the extracellular domain of CTLA-4. In order for a T cell to be activated and produce an immune response, an antigen-presenting... [wikipedia]