‘A Milestone’: Harvard Affiliated Physicians Perform First-Ever Pig Kidney Transplant

Doctors at Harvard-affiliated Massachusetts General Hospital performed the world’s first successful pig-to-human kidney transplant last Thursday.

Richard Slayman, a patient at MGH, received the kidney transplant after being on hemodialysis for the past year. He previously underwent a human kidney transplant surgery in 2018 after being on dialysis for seven years.

Winfred W. Williams ’75, a nephrologist at MGH who helped perform the surgery, said while Slayman’s transplanted kidney performed well for the first four years, it began to “progressively fail” in its fifth year after surgery.

Williams said Slayman underwent dozens of surgical and radiological procedures last year to improve the kidney’s function, but none of the interventions were successful. According to Williams, the failed procedures caused Slayman to become “increasingly despondent and depressed.”

“At one point, he told me he thought he would not be able to go on,” Williams said.

This led Williams to pursue other less traditional options to improve Slayman’s condition.

“This is the time when I began to think about extraordinary options that might provide a remedy and hopefully provide him with a much-improved quality of life and a brighter future,” Williams said.

Leonardo V. Riella, a transplant nephrologist researching the feasibility of xenotransplantation, approached Williams with an idea to replace Slayman’s kidney with a kidney from a pig.

“CRISPR-Cas allowed us to do multiple gene edits on a pig so that we can make this kidney the most compatible possible to humans,” Riella said. “We felt that we had the right combination to push this to a first in-human trial.”

Williams was able to successfully convince Slayman to undergo the procedure along with convincing from Slayman’s longtime doctor Tatsuo Kawai.

“He saw this as not only a way to help himself, to improve his own quality of life,” Williams said. “But he thought it was also a way to provide hope for the thousands of people in need of a transplant themselves, and he thought that it was worth this experimental effort.”

Under the guidelines of “compassionate use,” the FDA granted permission for the transplant.

Kawai said he was “nervous” for Slayman about the procedure because of its experimental nature.

“I was very nervous because it’s the first time to put the pig kidney into a live human,” Kawai said. “No one has ever done that, so you cannot make any mistake.”

Riella said he prepared for the pig kidney transplant in a similar way that he would for a human kidney transplant.

“We tried to keep it as structured and as consistent as we do any of our clinical studies and transplant surgeries in general,” Riella said.

The most challenging part for the team was finding the right location for the kidney transplant.

“Which artery we can use, those are very limited, so that was a long, difficult process,” Kawai said.

Despite the challenges, the doctors were successful in the pig kidney transplant. Kawai said this surgery shows animal transplants can be performed.

“Patients don’t need to wait,” he said.

According to Wiliams, the surgeons will submit information about the surgery to the FDA in hopes of getting approval for future surgeries.

“We are going to look at how he does over a twelve-month period to see what the outcomes look like,” Williams said. “Once we assemble all of that data, we will present that to the FDA.”

Riella said the surgery could be a “game changer” for all patients who have advanced kidney disease and are currently “suffering on dialysis.”

“I think it’s going to revolutionize our transplant field and hopefully will lead to dialysis becoming a temporary treatment and obsolete in a few years,” he said.