• Incidence and severity of GI adverse events of Myfortic at 3 months [ Time Frame: 2, 6 and 12 weeks ] [ Designated as safety issue: Yes ]
• assessment of GI tolerability using a GI symptom rating scale 2 weeks, 6 weeks, and 3 months after initiation of the drug [ Time Frame: 2, 6 and 12 weeks ] [ Designated as safety issue: No ]
• incidence of biopsy-proven acute cellular rejection during the study period [ Time Frame: 2, 6 and 12 weeks ] [ Designated as safety issue: Yes ]
• incidence of graft loss or death during the study period [ Time Frame: 2, 6 and 12 weeks ] [ Designated as safety issue: Yes ]
• assessment of renal- and neurotoxic-sparing effects during the study period [ Time Frame: 2, 6 and 12 weeks ] [ Designated as safety issue: Yes ]
• assessment of neurotoxic-sparing effects during the study period [ Time Frame: 2, 6 and 12 weeks ] [ Designated as safety issue: Yes ]

• Incidence and severity of GI adverse events of Myfortic at 3 months
• assessment of GI tolerability using a GI symptom rating scale 2 weeks, 6 weeks, and 3 months after initiation of the drug
• incidence of biopsy-proven acute cellular rejection during the study period
• incidence of graft loss or death during the study period
• assessment of renal- and neurotoxic-sparing effects during the study period
• assessment of neurotoxic-sparing effects during the study period

• Incidence and severity of leukopenia during the study period [ Time Frame: 2, 6 and 12 weeks ] [ Designated as safety issue: Yes ]
• incidence of cytomegalovirus infection or disease during the study period [ Time Frame: 2, 6 and 12 weeks ] [ Designated as safety issue: Yes ]

• Incidence and severity of leukopenia during the study period
• incidence of cytomegalovirus infection or disease during the study period

The objective of this study is to compare the safety and efficacy of Myfortic with CellCept in liver transplant patients. Myfortic and CellCept are both immunosuppressive (anti-rejection) drugs. CellCept is commonly used after liver transplantation but gastrointestinal (GI) side effects are very common, sometimes necessitating in its discontinuation. Myfortic is a new drug similar to CellCept, except it is enteric-coated. Our hypothesis is that Myfortic has less GI side effects than CellCept and also has comparable effectiveness to CellCept.

This is a prospective, randomized, double-blinded, single center, safety and efficacy study comparing Myfortic with CellCept used after liver transplantation. Patients with biopsy-proven acute cellular rejection, renal insufficiency (i.e. acute or chronic renal failure requiring hemodialysis or patients with creatinine clearance < 50 ml/min), or calcineurin inhibitor-induced neurotoxicity (defined as the presence of neurologic symptoms such as tremors, altered mental status, seizures, etc) will be randomized to start on either Myfortic (720 mg po bid) or CellCept (1 gm po bid). In those patients with calcineurin-induced neurotoxicity or nephrotoxicity, tacrolimus or cyclosporine doses will also be reduced to maintain serum trough levels of 4-8 mg/dl or 100-200 mg/dl, respectively.

Comparison: Thirty patients will be enrolled and randomized in this two-armed, double-blinded study— half of the patients will receive Myfortic and the other half, CellCept.

• Drug: Myfortic
• Drug: CellCept

Inclusion Criteria:

• ALL patients will be adult liver transplant recipients, males or females, 18-80 years of age.
• Patients must be 30 to 180 days (1 to 6 months) post-transplant to be eligible.
• Patients currently receiving tacrolimus or cyclosporine with or without corticosteroids as part of their immunosuppressive regimen.
• Patients with renal insufficiency (history of renal insufficiency or renal failure in the past, patients on hemodialysis, patients with a rising creatinine post-transplant).
• Patients with biopsy-proven acute cellular rejection (mild, moderate, or severe based on Rejection Activity Index (RAI) as graded by pathologists at UPMC) or repeated bouts of rejection (greater than 2 episodes within a 30 day period).
• Patients with tacrolimus- or cyclosporine-induced neurotoxicity.
• Females of childbearing potential must have a negative serum pregnancy test prior to the inclusion period.

Exclusion Criteria:

• Multi-organ transplant patients.
• HIV positive patients.
• Living-related liver transplant recipients
• Pregnant patients and nursing mothers.
• Patients with a history of extra-hepatic malignancy within the last five years, except excised squamous or basal cell carcinoma of the skin.
• Patients with thrombocytopenia (<50,000/mm3), with an absolute neutrophil count of <1,000/mm3 and/or leukocytopenia (<2,000/mm3), and/or hemoglobin <7.0 g/dL prior to enrollment.
• Presence of clinically significant infection requiring continued therapy, severe diarrhea, active peptic ulcer disease, or uncontrolled diabetes mellitus.
• Evidence of drug and/or alcohol abuse.
• Decisionally impaired subjects who are not medically or mentally capable of providing consent themselves