• An American man lived with a genetically modified pig kidney for a record period before it was removed
• He has now returned to dialysis while remaining on the waiting list for a human kidney

Doctors removed a genetically modified pig kidney from a man in the United States after he lived with it for a record 271 days, and he has now returned to dialysis

Tim Andrews, 67, who lives in New Hampshire, received the transplant in January, but surgeons at Mass General Brigham removed the organ due to declining kidney function

Andrews was the fourth living patient in the U.S. to receive a kidney from a genetically modified pig

He had been living with diabetes since the 1990s and learned about three years ago that he had end-stage kidney disease

Although dialysis saved his life, it was exhausting; he was connected to the machines for six hours, three times a week, and on days off he would sleep to recover before starting the process all over again

Andrews knew that trying an animal-to-human transplant carried risks, but he said it was worth it if it could keep him off dialysis and help other people with kidney problems

As Andrews returns to dialysis, he will remain on the waiting list for a human kidney transplant