The purpose of this study is to compare renal transplant recipients on cyclosporine maintenance therapy vs. those converted to tacrolimus-based immunosuppression with respect to renal outcomes.

The objective of this study is to compare the incidence, progression and severity of chronic renal allograft failure in at-risk patients who are converted from cyclosporine to tacrolimus-based immunosuppression to patients who remain on cyclosporine.

Inclusion Criteria:

• Patient is at least 3 months post-transplant of a cadaveric or living donor kidney

• Patient has been on a cyclosporine-based immunosuppression regimen since the transplant

• Patient has one of the following risk factors for chronic renal allograft failure at the baseline biopsy:

  • Serum creatinine: Male: >=2.0mg/dL (176.8 umol/L); Female: >= 1.7mg/dL (150.28 umol/L) 3 months or later post-transplant
  • Serum creatinine > 30% increased over post-discharge nadir

• Patient has had a renal biopsy > 3 months after transplant and within 6 months prior to enrollment

• Patient or legal guardian has signed and dated an IRB approved informed consent document

• Female patient has a negative pregnancy test and agrees to practice effective birth control while receiving mycophenolate mofetil (MMF)

Exclusion Criteria:

• Patient is dialysis dependent and has recurrence of primary or de novo renal disease
• Patient has an estimated creatinine clearance <25mL/min
• Patient has changed maintenance immunosuppressant therapy (e.g., azathioprine to MMF) within 3 months of randomization
• Baseline biopsy shows acute rejection Grade >=IIB using Banff 95 criteria or >= Grade IIA using Banff 97 criteria
• Patient requires antilymphocyte therapy to treat rejection at baseline or post-baseline biopsy
• Patient has received an investigational immunosuppressant within 3 months, or has a known hypersensitivity to tacrolimus, or any excipients of the drug
• Patient is a known carrier of any of the HIV viruses