Man survives 271 days on GM pig kidney before human transplant

In a global medical first, a 66-year-old man from New Hampshire lived for 271 days—nearly nine months—without requiring dialysis after receiving a genetically modified pig kidney. The procedure, performed in January 2025 at Massachusetts General Hospital, marked the world’s inaugural successful use of a porcine organ as a temporary bridge to a subsequent human kidney transplant.

How the Pig Kidney Served as a Bridge

The organ came from a miniature Yucatan pig named Wilma, whose genome had been edited to reduce immune rejection in humans. Doctors described the transplant as a “bridge” intervention: it sustained Tim Andrews while he awaited a compatible human donor. Andrews, who had end-stage kidney failure due to type 2 diabetes, began producing urine immediately after implantation and remained dialysis-free for the full 271-day period.

Approximately six months post-transplant, vascular damage developed in the pig kidney, leading to organ failure. The graft was surgically removed, and Andrews underwent a brief period of dialysis before receiving a human kidney from a deceased donor.

Record-Breaking Survival and Clinical Significance

This case represents the longest documented interval without dialysis following a pig kidney transplant in a living human—and the first verified transition from a xenotransplant to a human allograft. Medical teams confirmed no porcine endogenous retroviruses or other zoonotic pathogens were detected at any point during monitoring.

Researchers emphasized that the results reinforce the potential of pig kidney transplantation as a viable bridging strategy for patients enduring prolonged waits for human organs. They stressed, however, that further study is required before clinical adoption can be considered.

Publication and Expert Commentary

The findings were recently published in The Lancet by a collaborative team from academic institutions and hospitals centered at Massachusetts General Hospital. Dr. Leonardo Rella, lead author and director of the Transplant Science Center at Massachusetts General Hospital, stated: “Organ shortage is the greatest crisis we face in transplantation today. We know transplantation is the optimal treatment for end-stage kidney disease—but we simply do not have enough human organs available in time. Xenotransplantation offers a pathway to close this gap, either as a temporary bridge or, potentially, as a permanent solution in the future.” He also commended the courage of patients enabling such advances.

A prior pig kidney transplant conducted at Massachusetts General Hospital in 2024 resulted in 52 days of survival in another living patient, who later died from cardiac complications unrelated to the xenograft.

In a CNN documentary, Andrews called the pig kidney transplant “a miracle,” noting he regained the ability to cook, clean his home, and take extended walks with his dog.