Study of Stem Cell Infusion With Conditioning to Stop Immunosuppressive Drugs in Adults With Well-Functioning Living-Donor Liver Transplants

What this Trial Is About

Researchers are evaluating a new approach to help adult liver transplant recipients safely stop using lifelong immunosuppressive drugs, which often cause serious side effects. This study focuses on patients who have a well-functioning liver transplant from an HLA-matched living donor. The aim is to determine if these patients can stop their immunosuppressive medications without harming the transplanted liver by using a combination of conditioning treatments and donor stem cell infusion to retrain the immune system to accept the liver as its own. Participants will undergo an outpatient conditioning regimen lasting two weeks, which includes total lymphoid irradiation TLI and rabbit anti-thymocyte globulin rATG. On the final day, they will receive an infusion of donor hematopoietic stem and progenitor cells HSPCs collected from the same living donor. After treatment, participants will be closely monitored for graft function, donor cell presence in the blood, and signs of rejection or graft-versus-host disease. Tacrolimus, a common immunosuppressive drug, will be gradually reduced starting at six months, aiming for complete withdrawal by 10 to 12 months if certain safety and function criteria are met. During the study, patients will have regular blood tests, liver biopsies, and immune system assessments to track their progress. Researchers will measure the percentage of participants able to stop immunosuppressants by 12 months and monitor for any rejection or graft failure for up to 48 months after the stem cell infusion. The study will last several years, including long-term follow-up to ensure the safety and success of this delayed tolerance approach pioneered at UCLA.

Immune Tolerance Induction After Liver Transplantation