This study was done to find out which treatment, tacrolimus or sirolimus, leads to better long-term kidney function in kidney transplant patients.

The aim of this study was to compare the complete avoidance of calcineurin inhibitors (CI) using a sirolimus-based immunosuppressive regimen to a tacrolimus-based regimen in kidney transplantation. This study was a prospective open-label trial randomizing patients to receive tacrolimus, mycophenolate mofetil and prednisone or sirolimus, mycophenolate mofetil and prednisone. All patients received antithymocyte globulin induction. All rejection episodes were proven by biopsy. The hypothesis was that CI free immunosuppression after kidney transplantation will lead to an increase in glomerular filtration rate (GFR) at one year after kidney transplantation.

Inclusion Criteria:

• Living and deceased donor kidney transplant recipients at the Mayo Clinic, Rochester, Minnesota

Exclusion Criteria:

• Patients with type 1 diabetes less than 50 years of age who receive a living donor kidney transplant followed by a pancreas transplant
• Pediatric patients (<18 years of age)
• Multi-organ transplants (e.g., kidney-pancreas, kidney-liver)
• ABO-incompatible or positive crossmatch recipients (ABO incompatibility is an immune system reaction that occurs when blood from two different and incompatible blood types are mixed together.)
• Patients with severe hyperlipidemia (serum cholesterol >350 mg/dl or serum triglycerides >500 mg/dl
• Patients with severe leukopenia (White Blood Cell count [WBC]<3000 10^3/ml)
• Patients unwilling to return to the transplant center for late follow-up visits
• Body mass index (BMI) ≥ 32 with incisional problems post transplant (as determined by renal transplant surgeon