Study Evaluating Conversion From Tacrolimus to Sirolimus in Stable Kidney Transplant Recipients Receiving Myfortic

Inclusion Criteria I (-1 to 7 days post renal allograft transplant):

• Male or female patient 18 years of age or older.
• Patient has been fully informed of study procedures and requirements, has signed an IRB approved consent form and is willing and able to follow study procedures.

Exclusion Criteria I (-1 to 7 days post renal allograft transplant):

• Patient has previously received an organ transplant.
• Patient has an identified donor specific antibody prior to transplant
• Patient is known to be seropositive for the human immunodeficiency virus (HIV).
• Patient has active Hepatitis C or B infection documented by a positive DNA PCR. Patients who are seropositive for Hepatitis C virus (HCV) or B virus (HBV) but have negative HCV-RNA or HBV-DNA by PCR may be included.
• Patient has a current malignancy or a history of malignancy within the past 5 years, except non-metastatic basal or squamous cell carcinoma of the skin that has been treated successfully.
• Patient has an uncontrolled infection or unstable medical condition that could interfere with the study objectives.
• Patient is currently taking or has been taking an investigational drug in the past 30 days.
• Patient has a known hypersensitivity to sirolimus or Myfortic®.
• Patient is pregnant or lactating.
• Patient is unlikely to comply with the visits scheduled in the protocol.
• Patient has any form of substance abuse, psychiatric disorder or a condition that, in the opinion of the investigator, may invalidate communication with the investigator.

Inclusion Criteria II (90 - 180 days post renal allograft transplant):

• Patient is 90 to 180 days after having received a primary living- or cadaver-donor renal allograft
• Patient has been maintained on a regimen of tacrolimus, Myfortic® and corticosteroids prior to study enrollment.
• Patient has a stable allograft defined as calculated GFR > 30 mL/min using Nankivell equation.
• Patient has been fully informed of study procedures and requirements, has signed an IRB approved consent form and is willing and able to follow study requirements.
• Female patients of child bearing potential must use at least one reliable form of contraception unless they are status post bilateral tubal ligation, bilateral oophorectomy or hysterectomy. Effective contraception must be used for the duration of the study.

Exclusion Criteria II (90 - 180 days post renal allograft transplant):

• Patient has experienced an acute graft rejection of ≥ Banff '97 1b or humoral rejection as determined by biopsy within the first 90 days post-transplant
• Patient has experienced an acute graft rejection of ≤ Banff 97 1a as determined by biopsy within 30 days prior to Baseline visit.
• Patient has untreated hypercholesterolemia defined as triglycerides > 300 or total cholesterol >200 within the previous 30 days.
• Patient is currently (< 7 days) leukopenic defined as WBC < 3,000 cells/mL or thrombocytopenic defined as platelets < 100,000 cells/mL.
• Patient has significant liver disease, defined as having during the past 30 days continuously elevated AST (SGOT) and/or ALT (SGPT) levels greater than 3 times the upper value of normal range.