Optima: Optimizing Prograf Therapy in Maintenance Allografts II

• Patient is the recipient of a cadervic or living donor renal transplant.
• Patient was 18 years of age at time of transplant.
• Patient is at least 6 months post-transplant.
• Patient has been on a cyclosporine-based immunosuppressive regimen since the transplant.
• Patient has a functioning allograft and a Cockcroft/Gault estimate of creatinine clearance >or= 35 mL/min within four weeks prior to randomization.
• Patient or legal guardian has signed and dated an Institutional Review Board (IRB) approved informed consent document and is willing and able to follow study procedures.
• Females are not pregnant and agree to practice effective birth control while receiving immunosuppressant medication.

Exclusion Criteria:

• Patient is the recipient of a solid organ transplant other than the kidney.
• Patient experienced biopsy-confirmed, acute rejection, (Banff 97 criteria)within 3 months before randomization that required treatment, which is defined as antilymphocyte therapy, corticosteroids, or an increase in the number or dose of immunosuppressant medication.
• Patient has recurrence of primary renal disease, or de novo renal disease.
• Patient has a urine protein of > 1.5g/24 hours or two successive urinalyses sent to and reported by the laboratory indicating albuminuria greater than 2+ within 6 months prior to enrollment.
• Patient has an estimated creatinine clearance \< 35 mL/min calculated using Cockcroft/Gault formula within four weeks prior to randomization.
• Patient has changed adjunctive immunosuppressant therapy within one month if randomization.
• Patient is pregnant or lactating.
• Patient is a known carrier of any of the HIV viruses.
• Patient has a known or suspected malignancy (except for treated squamous or basal cell skin cancers) \< 5 years before randomization or a history of post-transplant lymphoproliferative disease (PTLD).
• Patient has a known hypersensitivity to tacrolimus, or any of the excipients of the drug.