Inclusion Criteria:

• Men and women 18-65 years of age who are recipients of a liver transplant at least six months prior to enrollment
• Patients on oral Prograf therapy as part of their maintenance immunosuppression therapy, with stable doses and trough levels of tacrolimus of 5-12 ng/mL for at least four weeks prior to enrollment with at least two measurements at least two days apart in the screening period up to fourteen days prior to enrollment
• Concurrent immunosuppression with mycophenolate mofetil (MMF, CellCept) or mycophenolic acid delayed-release tablets (Myfortic) is allowed but patients on either of these medications should be on stable doses for at least four weeks prior to enrollment
• Patients with stable serum bilirubin, AST, ALT, and Alk Phos or GGT that are ≤ 2 times the upper limit of normal based on local laboratory criteria
• Patients with serum creatinine ≤2.0 mg/dL prior to enrollment
• Able to swallow study medication
• Patients capable of understanding the purposes and risks of the study, who can give written informed consent and who are willing to participate in and comply with the study protocol.
• Women of childbearing potential must have a negative serum pregnancy test within seven days prior to receiving study medication and agree to use contraceptive measures to avoid pregnancy during participation in the trial.

Exclusion Criteria:

• Recipients of any transplanted organ other than a liver
• White blood cell count ≤ 2.8 x 109/L
• Patients who are receiving a total dose of Prograf < 3 mg per 24 hours
• Patients who are receiving more than 10 mg of prednisone per day
• Patients unable or unwilling to provide informed consent
• Pregnant or nursing women
• Patients with reproductive potential who are unwilling/unable to use a double barrier method of contraception
• Administration of any other investigational agent in the three months prior to enrollment
• Patients receiving any drug interfering with tacrolimus metabolism
• Patients who have taken sirolimus within the three months prior to screening
• Patient with an episode of acute cellular requiring antibody therapy within the six months prior to enrollment
• Patients treated for acute cellular rejection within the thirty days prior to enrollment
• Patient who is HCV negative and has received an HCV positive (HCV RNA by PCR or HCV antibody) donor liver
• Patients presenting after liver transplantation with recurrent HCV infection, documented by presence of HCV RNA in serum and grade II or greater inflammation or stage II or greater fibrosis on liver biopsy
• Patients being actively treated with antiviral therapy, such as interferons or ribavirin, for recurrent hepatitis C.
• Patients with an alpha-feto protein ≥ 20 ng/mL
• Patient has a current malignancy or a history of malignancy (within the past five years), except basal or non-metastatic squamous cell carcinoma of the skin that has been treated successfully
• Patient has uncontrolled concomitant infection, a systemic infection requiring treatment, or any other unstable medical condition that could interfere with the study objectives
• Patient has severe diarrhea, vomiting, active peptic ulcer or gastrointestinal disorder that may affect the absorption of tacrolimus
• Patient will require therapy with any immunosuppressive agent other than those prescribed in the study
• Patient has a known hypersensitivity to corticosteroids or tacrolimus
• Patient has any form of current substance abuse (patients must pass a standard drug screen), psychiatric disorder or a condition that, in the opinion of the Investigator, may invalidate communication with the Investigator Version