Overview
- A peer‑reviewed study published in The Lancet on Thursday reported a genetically modified pig kidney functioned for 271 days in a U.S. patient, the longest recorded duration to date.
- The patient, Tim Andrews, received the porcine kidney in January 2025 and avoided months of dialysis before the animal graft was removed and he later received a human kidney in January 2026.
- Six months after the transplant the patient was hospitalized with a methicillin‑resistant Staphylococcus aureus infection; clinicians reduced immunosuppression and the porcine graft deteriorated, prompting its removal after 271 days of function.
- The donor pigs underwent extensive editing—reported as 69 genetic changes—to remove pig immune triggers and deactivate porcine viral elements used to lower rejection and cross‑species infection risk.
- Clinicians say the case shows xenotransplantation can serve as a temporary bridge to human organs but that infection control and the balance of immunosuppression are key unresolved issues before wider use.