BALTIMORE — Surgeons in the United States have successfully implanted a genetically modified pig’s heart into a 57-year-old man, a medical first that could one day help solve the chronic shortage of organ donations.
The “historic” trial took place last Friday, the University of Maryland School of Medicine said in a statement Monday. Although the patient’s prognosis is far from certain, it represents an important milestone for animal-to-human transplantation.
The patient, David Bennett, was deemed unsuitable for human transplantation – a decision often made when the recipient is in very poor health.
He is now recovering and being carefully monitored to see how the new organ is working.
“Either die or do this transplant. I want to live. I know it’s a shot in the dark, but it’s my last choice,” the Maryland resident said a day before the surgery.
Bennett, who has been bedridden on a cardiopulmonary bypass machine for the past few months, added, “I can’t wait to get out of bed after I recover.”
The Food and Drug Administration issued emergency medical clearance for the surgery on New Year’s Eve as a last-ditch effort for a patient unsuitable for a conventional transplant.
“This was a groundbreaking operation and brings us one step closer to solving the organ shortage,” said Bartley Griffith, who surgically transplanted the pig’s heart.
“We are proceeding with caution, but we are also optimistic that this world-first surgery will provide patients with an important new option in the future.”
Surgeon Dr. Bartley Griffith (L) with patient David Bennett, who received a heart implant from a genetically modified pig, in Baltimore, Maryland.
Muhammad Mohiuddin, co-founder of the university’s heart xenotransplantation program, added that the operation was the culmination of years of research which has seen transplants from pigs to baboons with survival times in excess of nine months. .
“The successful procedure provided valuable information to help the medical community improve this potentially life-saving technique in future patients,” he said.
Bennett’s donor pig was from a herd that had undergone genetic interventions.
Three genes that would have caused humans to reject pig organs were “knocked out”, as was a gene that would have caused pig heart tissue to proliferate.
Six human genes responsible for human acceptance were inserted into the genome for a total of 10 unique genetic modifications.
The editing was done by Virginia-based biotech company Revivicor, which also provided the pig used in a landmark kidney transplant in a brain-dead patient in New York City in October.
But while this surgery was purely a proof-of-concept experiment and the kidney was plugged outside of the patient’s body, the new surgery aims to save a person’s life.
The donated organ was stored in an organ preservation machine before surgery, and the team also used an experimental new drug from Kiniksa Pharmaceuticals along with conventional anti-rejection drugs to suppress the immune system.
About 110,000 Americans are currently waiting for an organ transplant, and more than 6,000 patients die each year before receiving one, according to official figures.
To keep up with demand, doctors have long been interested in what’s called xenotransplantation, or cross-species organ donation, with experiments dating back to the 17th century.