The University of Maryland Medical Center (UMMC) in the US announced on Wednesday that David Bennett has died, roughly two months after becoming the first-ever human to receive a genetically modified pig's heart.
"We are devastated by the loss of Mr. Bennett. He proved to be a brave and noble patient who fought all the way to the end. We extend our sincerest condolences to the family," said Bartley P. Griffith, who conducted the surgery.
Bennett received the heart transplant on January 7 and passed away on March 8.
"His condition began deteriorating several days ago. After it became clear that he would not recover, he was given compassionate palliative care. He was able to communicate with his family during his final hours," the statement from the hospital said.
First-of-its-kind transplant
Bennett was admitted to UMMC in October in need of a heart transplant but was classified as ineligible for a conventional heart transplant.
To keep him alive, he was placed on a heart-lung bypass machine. The transplant was his last option.
The US Food and Drug Administration gave emergency authorization for doctors to carry out the pig-to-human heart transplant on December 31.
This first-of-its-kind surgery only recently became a valid option thanks to developments in gene editing tools. The heart given to Bennett had been genetically modified to prevent rejection.
Experts have long looked to pig organs as a potential source for transplants due to their similarity with humans, but organ rejection and increased viral infection risk meant that prior efforts had failed.
Doctors still 'optimistic' about pig-to-human transplants
Bennett's son called the procedure a "miracle." His new heart functioned "very well for several weeks without any signs of rejection," the hospital said on Wednesday.
"Before consenting to receive the transplant, Mr. Bennett was fully informed of the procedure's risks, and that the procedure was experimental with unknown risks and benefits," the statement added.
Doctors at the UMMC said that despite the loss, the experience had helped them learn and they "remain optimistic and plan on continuing our work in future clinical trials," Muhammad Mohiuddin, director of the university's cardiac xenotransplantation program, said.
"We have gained invaluable insights learning that the genetically modified pig heart can function well within the human body while the immune system is adequately suppressed."