• Proportion of patients who suffer graft loss or die following initiation of immunosuppression withdrawal [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]
• time from start of immunosuppression to the first episode of acute rejection or to diagnosis of chronic rejection [ Time Frame: Immunosuppression to first acute rejection or diagnosis of chronic rejection ] [ Designated as safety issue: Yes ]
• distribution of histologic severity among rejection episodes [ Time Frame: Immunosuppression to rejection ] [ Designated as safety issue: Yes ]
• incidence of adverse events [ Time Frame: throughout trial ] [ Designated as safety issue: Yes ]
• changes in renal function, blood pressure, cholesterol level, and glucose control [ Time Frame: throughout trial ] [ Designated as safety issue: Yes ]

• Proportion of patients who suffer graft loss or die following initiation of immunosuppression withdrawal
• time from start of immunosuppression to the first episode of acute rejection or to diagnosis of chronic rejection
• distribution of histologic severity among rejection episodes
• incidence of adverse events
• changes in renal function, blood pressure, cholesterol level, and glucose control

Antirejection medicines, also known as immunosuppressive drugs, are prescribed to organ transplant recipients to prevent their bodies from rejecting the new organ. Long-term use of these drugs places transplant recipients at higher risk of serious infections and certain types of cancer. The purpose of this study is to determine whether immunosuppressive drugs can be safely withdrawn over a minimum of 9 months from children who received liver transplants at least 4 years ago.

In order to prevent the rejection of transplanted organs, transplant recipients are prescribed a strict, lifelong regimen of immunosuppressive drugs. While these drugs help prevent the body from rejecting the transplant, they carry numerous complications, including increased risk of serious infections and certain types of cancer. However, there is mounting evidence that a significant percentage of liver transplant recipients can maintain a healthy, functioning transplant without ongoing immunosuppression. This study will determine whether gradual withdrawal and eventual discontinuation of all immunosuppressive medication can be safely accomplished in children who received a liver transplant from a parent. Twenty eligible patients who were under 18 years old at the time of transplant, whose donor was a parent, and who received the transplant at least four years ago will be enrolled in the study.

Liver recipients will have an initial screening assessment consisting of a medical history, liver biopsy, and urine and blood collection. Eligible recipients will be placed on a modified medication schedule to gradually decrease their immunosuppression medication slowly over a 9- to 12-month period, during which time they will be closely monitored by study staff. Immunosuppressive drugs will not be provided by this study. For a minimum of 3 and up to a maximum of 7 years, monthly telephone consultations and quarterly study visits will occur. Visits will include physical exams and blood collection to monitor the children's health during the withdrawal phase. The exact schedule of immunosuppressant withdrawal will be determined by study physicians based on participant's health and immune function test results. Donor and nondonor parents will be asked to each provide one blood sample during the initial study visits for immunologic and genetic testing.

*** IMPORTANT NOTICE: *** The National Institute of Allergy and Infectious Diseases and the Immune Tolerance Network do not recommend the discontinuation of immunosuppressive therapy for recipients of cell, organ, or tissue transplants outside of physician-directed, controlled clinical studies. Discontinuation of prescribed immunosuppressive therapy can result in serious health consequences and should only be performed in certain rare circumstances, upon the recommendation and with the guidance of your health care provider.

• Liver Transplantation
• Immunosuppression

Inclusion Criteria for Liver Recipients:

• Received liver from living parent donor
• Received transplant at least 4 years prior to study entry
• Less than 18 years of age at time of transplant
• Parent or guardian willing to provide informed consent

Inclusion Criteria for Liver Donors:

• Willing to participate in this study

Exclusion Criteria for Liver Recipients:

• Underwent transplant because of liver failure related to autoimmune disease
• Underwent transplant of a second organ simultaneously with or after liver transplant OR liver retransplantation
• Receiving immunosuppression with more than one drug
• 50% increase in dose of current immunosuppressive drug
• HIV infection
• Hepatitis B or C virus infection
• Pregnancy or breastfeeding