MDR-103 + Total Lymphoid Irradiation + anti-thymocyte globulin

MDR-103 + Total Lymphoid Irradiation + anti-thymocyte globulin is an investigational combination regimen developed by Medeor Therapeutics for the induction of delayed immune tolerance and mixed chimerism in patients who have previously received an HLA-matched living donor kidney transplant. The regimen consists of MDR-103, a donor-derived cellular immunotherapy containing enriched CD34+ hematopoietic stem and progenitor cells along with a defined dose of T cells, administered following a non-myeloablative conditioning regimen of low-dose total lymphoid irradiation (TLI) and anti-thymocyte globulin (ATG). This combination is designed to establish persistent mixed lymphohematopoietic chimerism, allowing the recipient's immune system to coexist with the donor cells and ultimately enabling the complete withdrawal of chronic immunosuppressive maintenance therapy without risking graft rejection or graft-versus-host disease (GvHD). A Phase 2 trial evaluating this combination was withdrawn prior to enrollment due to a lack of funding.