Although anti-TNF therapy is successful at controlling disease activity in patients with rheumatoid arthritis (RA), there are those who have an inadequate or unsustained response. Abatacept, also known as CTLA4g, blocks a co-stimulatory signal required for T cell activation. In the ATTAIN trial (Abatacept Trial in the Treatment of Anti-TNF INadequate RA Responders), Genovese, et al (N Engl J Med 2005;353:1114-23) evaluated the efficacy and safety of abatacept in a group of TNF-refractory RA patients.
A summary of the data from this study was summarized in an abstract presented during the 2004 American College of Rheumatology meeting. Overall, using ACR response criteria, patients receiving abatacept had significantly greater improvements in their disease activity than those receiving placebo.