Tom Andrews preparing for surgery. KateFlock/Massachusetts General Hospital.

Tim Andrews, 66, received a transplant of a genetically modified porcine kidney in January 2025. The procedure was performed at Massachusetts General Hospital in Boston, and Andrews lived with the kidney for 271 days. During that period, he was able to stop dialysis, which had kept him alive until then.

In a study published earlier this month in the medical journal The Lancet, the team that performed the procedure explains that animal organ transplants — known as xenotransplants — could be used as a “bridge” while patients wait for a suitable human organ to become available.

The kidney was developed with 69 genetic modifications to prevent Andrews’ body from identifying the new organ as a foreign body. This medical and scientific challenge set a record for the longest-lasting animal-to-human transplant, with the organ surviving for nine months.

Eventually, the organ failed and surgeons had to remove it. Andrews returned to dialysis, but a suitable human donor became available shortly afterwards. As he explained, the porcine kidney transplant gave him “hope” because he had very little time left and, most importantly, it allowed him to “get off the dialysis machine and live life.”

Leonardo Riella, medical director of the kidney transplant program at Massachusetts General Hospital and the study’s lead author, said that the biggest current crisis in the field of transplantation is the shortage of organs. For this reason, he believes that “xenotransplantation could help address this shortage.”

Source: El País