Man Lives With Pig Kidney for Nine Months in World First
A US man has lived with a pig kidney for nine months, setting a new record for the longest reported survival with a genetically engineered animal kidney before receiving a human donor organ. Tim Andrews, 66, remained off dialysis for 271 days after receiving the modified pig kidney in January 2025.
The case was described in a Lancet research paper and involved doctors from Harvard Medical School, Massachusetts General Hospital, and associated hospitals. The transplant offers new evidence that a pig kidney transplant could potentially serve as a temporary option for patients waiting for a suitable human donor.
The man who lived with a pig kidney for nine months received the organ under a USFDA Expanded Access Investigational New Drug application. The kidney started functioning immediately after surgery, although doctors detected an immune response on the 14th day. Treatment controlled the early rejection, and the organ continued working for about six months.
The major setback came after Andrews developed a bacterial infection that was not linked to the pig kidney. Doctors reduced his immunosuppressive medicines, after which inflammation damaged blood vessels inside the organ. Microscopic blood clots developed, eventually causing the kidney to lose function.
The pig kidney transplant was followed by a human donor kidney after the animal organ stopped functioning. The new kidney worked immediately. Doctors also found that Andrews had not developed higher levels of anti-HLA antibodies, suggesting the earlier transplant had not increased his immune response against a later human kidney.
The case is important for xenotransplantation, which involves transferring organs from animals to humans. Experts cited in the report said the longer survival period provides evidence that genetically engineered organs could eventually help address the shortage of human donor kidneys.
For India, the development has particular relevance because nearly two lakh new patients reportedly require kidneys each year, while only around 14,500 transplants are performed. A genetically engineered pig kidney could eventually provide a temporary bridge for patients without a suitable living donor.
However, xenotransplantation still faces challenges involving infection surveillance, rejection, immunosuppression, regulation, ethics, specialised infrastructure and affordability. In India, changes to the Human Organ Transplant Act would also be required before such procedures could become part of routine clinical practice.