US surgeons perform first living transplant of genetically-edited pig kidney

A 62 year old man living with kidney failure has become the first person to receive a successful transplant of a pig kidney, which was genetically modified to reduce the risk of his body rejecting the organ.

The four-hour surgery was performed on March 16, at Massachusetts General Hospital (MGH). The patient, Richard Slayman, was discharged from hospital two weeks after the surgery. His kidney is now functioning well and he is no longer on dialysis.

“The real hero today is the patient, Mr. Slayman, as the success of this pioneering surgery, once deemed unimaginable, would not have been possible without his courage and willingness to embark on a journey into uncharted medical territory,” said Joren C. Madsen, Director of the MGH Transplant Center.

Mr Slayman, who has also been living with type 2 diabetes and hypertension, previously received a kidney transplant from a deceased human donor in December 2018, performed at the same hospital, after having been on dialysis for seven years.

In May 2023 the transplanted kidney showed signs of failure and Mr Slayman resumed dialysis. He experienced recurrent dialysis vascular access complications requiring additional visits to the hospital every two weeks for de-clotting and surgical revisions.

Mr. Slayman said in a statement, “I have been a Mass General Transplant Center patient for 11 years and have the highest level of trust in the doctors, nurses, and clinical staff who have cared for me. When my transplanted kidney began failing in 2023, I again trusted my care team at MGH to meet my goals of not just improving my quality of life but extending it. My nephrologist and the Transplant Center team suggested a pig kidney transplant, carefully explaining the pros and cons of this procedure. I saw it not only as a way to help me, but a way to provide hope for the thousands of people who need a transplant to survive.”

One of the surgeons on the team, Dr Tatsuo Kawai, expressed hope that his approach "will offer a lifeline to millions of patients worldwide who are suffering from kidney failure". Right now, over 70,000 people in the UK are being treated for kidney failure.

Mass General kidney transplant
Massachusetts General Hospital transplant surgeons Dr Nahel Elias, left, and Dr Tatsuo Kawai perform the surgery of a transplanted genetically modified pig kidney into a living human

Fiona Loud, Policy Director at Kidney Care UK, said:

"Xenotransplantation has been discussed and studied for many years, with unsuccessful attempts in the 1990s. However now with gene editing and a greater understanding of preventing transmission of animal viruses there is much optimism for real progress.

"It is a topic that will generate a lot of debate and similar conversations took place 50 years ago when the first pig heart valve was used in an operation, yet thousands of life saving heart valve replacements involving valves from pigs take place every year now.

But we mustn't let this distract us from the work we need to do right now to improve organ donation rates in the UK and ensure more people are able to get a life saving kidney transplant. The waiting lists are the highest they have been in a decade and we must reduce this as soon as possible."

Find more information about this story on BBC News.