At the Albany Medical Center, we have a long-term experience, mean follow-up of 61 months, in 31 renal transplant recipients treated with sirolimus, cyclosporine microemulsion formulation, and prednisone. In these patients the rate of acute rejection was 13%, actual patient and graft survival at 1 year was 100%, and the mean serum creatinine at I year was 1.3 mg/dL. Furthermore, long-term graft survival was 90%. The success of this regimen stimulated us to evaluate a subsequent sirolimus-based protocol, initiated in April, 2001, which decreased exposure to calcincurin inhibitors at 3 months posttransplant (n = 50). At a mean follow-up of 10 months, graft survival was 96%. The rate of acute rejection was only 10% and the mean serum creatinine was 1.5 mg/dL. Furthermore, no acute rejection episodes have developed subsequent to the reduction in calcineurin inhibitor dosing at 3 months. Sirolimus is an effective immunosuppressive agent that safely allows for a reduction in calcineurin-inhibitor dosing.