To evaluate and to compare efficacy and safety of MR4 versus Prograf in patients undergoing primary liver transplantation.

Inclusion Criteria:

• Female patients of child bearing potential must have a negative in pregnancy test prior to enrollment and must agree to practice effective birth control during the study
• Patients who need liver transplantation due to the end-stage liver failure

Exclusion Criteria:

• Patients receiving multi-organ transplant or having previously received an organ transplant ( including re-transplantation)
• Patients receiving auxiliary graft or in whom a bio-artificial
• Patients allergic to macrolide antibiotics or tacrolimus
• Patients requiring immunosuppressive treatment or systemic chemotherapy prior to transplantation. Patients requiring low level immunosuppressive treatment ( MMF, steroids, azathioprine ) before transplantation to control their original liver disease can be included in the study, provided that this treatment is discontinued at the time of transplantation. Local chemotherapy is allowed
• Patients with malignancies of a history of malignancy within the last 5 years, with the exception of those with basalioma or squamous cell carcinoma of the skin that has been treated successfully Patients can be included under Milan Criteria Patients with malignancy which was identified after completion of surgery e.g. by histopathology will be allowed to remain in the study
• Patients with systemic infection requiring treatment, except viral hepatitis
• Patients with severe diarrhea, vomiting, active peptic ulcer or gastrointestinal disorder that may affect the absorption of tacrolimus
• Patients with serum creatinine > 1.5mg/Dl
• Patients with any form of substance abuse, psychiatric disorder of condition which, in the opinion of the investigator, may complicate communication with the investigator
• Patients participating or participated in another clinical trial or those taking or having taken an investigational / non-registered drug in the past 28 days
• Patients who are pregnant or breast-feeding mother
• Patients or donors known to be HIV positive
• Patients unlikely to comply with the visits scheduled in the protocol