• Incidence of acute rejection at 6 months post-transplant [ Time Frame: 6 months ] [ Designated as safety issue: Yes ]
  

• Graft and patient survival at 12, 24, 36, and 48 months post-transplant [ Time Frame: 12, 24, 36, and 48 months ] [ Designated as safety issue: Yes ]
  
• immunosuppressive-related and metabolic complications [ Time Frame: 48 months ] [ Designated as safety issue: Yes ]
  
• tolerance induction [ Time Frame: 48 months ] [ Designated as safety issue: No ]
  
• laboratory measures predictive of tolerance or rejection [ Time Frame: 48 months ] [ Designated as safety issue: No ]
  

Drugs that suppress the immune system, have contributed to increased success of transplantation. However, to prevent organ rejection, transplant recipients need to take immunosuppressive drugs for the rest of their lives; these drugs make patients more susceptible to infection and certain kinds of cancer. Belatacept is an experimental medication that specifically targets immune reactions against transplanted organs and has been shown to be effective in preventing kidney transplant rejection in previous clinical trials. Both thymoglobulin, an antibody, and sirolimus, an anti-rejection drug, prevent rejection by lowering the response of the immune system to the transplanted organ. .This study will evaluate whether belatacept, along with thymoglobulin and sirolimus, is safe in kidney transplant patients. The study will also evaluate this regimen's potential to allow tapering and eventual discontinuation of all immunosuppressive drugs.

This study will last up to 4 years. At the time of transplant, participants will begin a medication schedule consisting of thymoglobulin, sirolimus, and belatacept. Participants will receive infusions of thymoglobulin on days 1 though , and a combination of oral sirolimus (daily) and belatacept infusions at day 5, then weeks 2, 4, 8, and monthly for at least 2 years. Dose reduction of belatacept will occur at 12 weeks post-transplant. At Year 2, eligible participants may choose to begin drug withdrawal or continue study therapy through the end of the study. Study visits will occur weekly for the first two months, then monthly. These visits will include belatacept treatment, general medical assessments, blood and urine collection, and other assessments to determine overall health of the recipient's immune system and kidney transplant and to better understand the way the immune system works in the acceptance or rejection of organ transplants.