CTLA4 and rheumatoid arthritis: In RA patients who have an inadequate response to biologic DMARDs, CTLA4-Ig was recently observed to reduce the composite score of Disease Activity Score for 28 Joints based on the C-reactive protein level (DAS28/CRP) after 12 weeks of treatment, as well as the DAS28/CRP core components, such as tender joint count and swollen joint count of 28 joints, and the patient’s global assessment of disease activity [33].