First-Ever Pig Kidney Transplant Performed in Living Recipient

A 62-year-old man with end-stage kidney disease (ESKD) received the world’s first successful transplant of a genetically edited pig kidney, doctors in Boston announced.

The 4-hour surgery took place on March 16 at the Mass General Transplant Center in Boston and was led by Leonardo V. Riella, MD, PhD, medical director for kidney transplantation. The patient Richard ‘Rick’ Slayman of Weymouth, Massachusetts, is reportedly recovering well and is expected to be discharged soon.

“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,” Slayman said in a statement.

The pig kidney had 69 genomic edits using CRISPR-Cas9 technology, which deleted harmful pig genes that were replaced with certain human genes to boost human compatibility. Additionally, porcine endogenous retroviruses were inactivated in the pig donor to eliminate infection risk. Slayman also received an infusion of novel immunosuppressant drugs: the investigational anti-CD40 antibody tegoprubart and ravulizumab (Ultomiris), a humanized monoclonal antibody targeting the C5 protein.

The transplant was performed under the FDA expanded access protocol, also known as “compassionate use,” in which the FDA allows patients with no other treatment options to try experimental therapies.

Slayman had a long history of type 2 diabetes and hypertension, and was on dialysis for many years before receiving a kidney transplant from a deceased human donor in December 2018. The transplanted kidney showed signs of failure less than 5 years later, and dialysis was resumed in May 2023. Since resuming dialysis, Slayman has had recurrent dialysis vascular access complications requiring visits to the hospital every 2 weeks for de-clotting and surgical revisions.

This major step forward in transplantation comes less than a year after teams at two other institutions — the University of Alabama at Birmingham Heersink School of Medicine and the NYU Langone Transplant Institute in New York City — both successfully transplanted pig kidneys into two brain-dead men.

“At Massachusetts General Hospital alone, there are over 1,400 patients on the waiting list for a kidney transplant,” said Riella. “Some of these patients will unfortunately die or get too sick to be transplanted due to the long waiting time on dialysis. I am firmly convinced that xenotransplantation represents a promising solution to the organ shortage crisis.”

Over 100,000 patients in the U.S. are currently waiting on an organ for transplant, with the kidney being the most commonly needed organ. This number is only expected to rise, since ESKD rates are estimated to increase by 29% to 68% in the U.S. by 2030, impacting an estimated 971,000 to 1,259,000 patients.

This kidney transplant “also represents a potential breakthrough in solving one of the more intractable problems in our field, that being unequal access for ethnic minority patients to the opportunity for kidney transplants due to the extreme donor organ shortage and other system-based barriers,” said Winfred Williams, MD, also of Mass General, who is Slayman’s nephrologist. “This health disparity has been the target of many national policy initiatives for over 30 years, with only limited success.”

“An abundant supply of organs resulting from this technological advance may go far to finally achieve health equity and offer the best solution to kidney failure — a well-functioning kidney — to all patients in need,” he said.

Please enable JavaScript to view the

comments powered by Disqus.