The second person ever has received a transplant with a genetically modified pig kidney.
Tim Andrews, a 66-year-old who lives in Concord, N.H., has end-stage kidney disease and had been on dialysis for more than two years to compensate for his failing kidney function. He received the pig kidney at Massachusetts General Hospital on Jan. 25. as part of a new study authorized by the U.S. Food and Drug Administration (FDA), which will include a total of three patients.
Andrews was discharged on Feb. 1 and is staying in the Boston area for follow-up before returning home. Doctors say the transplanted pig kidney is functioning normally and producing urine.
The hope is that pig kidneys could help ease the organ-shortage problem in the U.S. According to the transplant team, Andrews had just a 9% chance of receiving a human kidney in the next five years, and a nearly 50% chance of being removed from the transplant wait list because of his deteriorating health. His dialysis left him unable to continue with many of his usually activities, and he had a heart attack in 2023. As of last September, nearly 90,000 people were waiting for a kidney, and in 2023, just over 27,000 transplants were performed—revealing the gap between demand and supply that xenotransplants, or animal-to-human transplants, could address.
How pig kidneys can work in humans
The challenge with this type of transplant is that the human body often rejects foreign tissue. Andrews’ pig kidney is possible because of several new genetic advances including cloning and the gene-editing platform CRISPR, which allowed scientists to modify the organ to make it more compatible with the human immune system. The company that created the the kidney, eGenesis, removed three major pig proteins on the organ, introduced seven human genes to reduce the chances it would be rejected, and disabled certain viruses in the pig genome that would have been harmful to the patient.
This process has been done once before. Richard…
