Feasibility Study of Stem Cell Infusion After Conditioning With Total Lymphoid Irradiation and Anti-thymocyte Globulin in Adults With Well-functioning HLA-Matched Kidney Transplants

What this Trial Is About

Researchers are studying whether patients with a well-functioning kidney transplant from an HLA-identical living donor can stop taking immunosuppressive medications safely by receiving an infusion of hematopoietic stem cells HPSC from the same donor. This study explores a process called retroactive tolerance induction, using a conditioning treatment of total lymphoid irradiation TLI and anti-thymocyte globulin ATG before the stem cell infusion. The goal is to avoid lifelong immunosuppression without harming the kidney transplant function. Participants will first undergo a conditioning regimen involving TLI and rabbit anti-thymocyte globulin rATG. Following this, they will receive an infusion of hematopoietic stem cells from their original HLA-identical kidney donor. After the infusion, researchers will monitor the patients to see if they can safely reduce and eventually stop immunosuppressive drugs like tacrolimus, starting at 6 months and aiming for full discontinuation by 12 months if certain conditions are met, including evidence of donor cell presence, stable kidney function, and no signs of graft versus host disease. Throughout the study, patients will have regular assessments to monitor kidney graft function and blood tests to measure chimerism, or the presence of donor cells, in different blood cell types. The main outcome measured is whether patients can successfully stop immunosuppression by 12 months. Secondary outcomes include monitoring for rejection and graft survival up to 48 and 24 months respectively. Participants will be followed closely for safety and kidney health during the trial period.

Delayed Immunological Tolerance in Patients With Well-functioning Pre-existing HLA-matched Kidney Transplants