Study to Evaluate the Safety and Efficacy of the GGTA1 KO Thymokidney in Patients With ESRD

The purpose of this study is to evaluate the safety and efficacy of the GGTA1 KO Thymokidney in patients with end-stage renal disease (ESRD) who are either not eligible for conventional allogeneic kidney transplantation (Group 1) or are on an Organ Procurement and Transplantation Network (OPTN) kidney transplant waitlist, but are more likely to die or go untransplanted within 5 years than receive a kidney transplant (Group 2). The study consists of xenotransplantation followed by a 24-week Post-transplant Follow-up Period (Part A) to evaluate the efficacy and safety objectives followed by a Long-term Follow-up Period (Part B) to evaluate participant survival, GGTA1 KO Thymokidney survival, and screening for zoonotic infections. Part B will continue for the lifetime of the participant or for 52 weeks following nephrectomy, if required.

This is a Phase 1/2/3, multicenter, open-label, safety and efficacy study of the GGTA1 KO Thymokidney in patients with ESRD. The study will be comprised of the following: * A Screening Period up to 52 weeks. * Part A consists of the GGTA1 KO Thymokidney transplantation followed by a 24-week Post-transplant Follow-up Period, including the evaluation of all study endpoints and safety assessments. * Part B is a Long-term Follow-up Period that extends for the lifetime of participants who received the GGTA1 KO Thymokidney or for 52 weeks following nephrectomy, if required, including but not limited to documentation of participant survival, GGTA1 KO Thymokidney survival, and screening for zoonotic infections. There will be 2 groups of participants enrolled in the study. Group 1 will be participants deemed ineligible for conventional allogeneic kidney transplantation due to medical reason(s). Group 2 will be participants on an OPTN kidney transplant waitlist but who are more likely to die or go untransplanted within 5 years than receive a kidney transplant. For the purpose of the primary analysis, the end of the study is defined as the date of the final visit of the final participant in Part A of the study.