Pig kidney lasts record 271 days in human transplant patient
What's the story
A pig kidney transplanted into a human has functioned for a record 271 days, according to doctors at Mass General Brigham hospital in the United States. The patient, Tim Andrews, received the transplant on January 25, 2025. The procedure was part of ongoing research into xenotransplantation, the use of animal organs for human transplants, to address organ shortages.
Transplant journey
How the procedure helped Andrews
Andrews, who was suffering from end-stage kidney disease due to type 2 diabetes, received the pig kidney as a temporary solution while waiting for a human donor.
The transplanted organ functioned well for nearly nine months before it failed and had to be removed in October 2025.
After a brief period of dialysis, Andrews received a human donor organ in January 2026.
Humanization process
Why Yucatan miniature pigs were chosen for the experiment
The success of the pig kidney transplant can be attributed to Yucatan miniature pigs that have undergone 69 genomic modifications to "humanize" their organs.
These changes help mask the pig tissue from the human immune system and disable viruses within pig DNA.
Despite initial signs of rejection, which were treated with medication adjustments, the organ eventually failed due to undetermined damage to blood vessels in the kidney.
Organ crisis
Organ transplant waiting list
The United States has a severe organ shortage, with around 100,000 people waiting for kidneys and only 25,000 transplants performed annually.
In the UK, over 7,000 people are on the kidney transplant list.
Dr. Leonardo Riella from Mass General Brigham's Center for Transplantation Sciences highlighted this crisis and said they are "working really hard to bring hope" through xenotransplantation as an alternative for patients without living donors.