A month after an experimental procedure to transplant the heart of a genetically modified pig into a patient with end-stage heart disease, doctors say the heart is functioning on its own and shows no signs of rejection.
In September, 58-year-old Lawrence Faucette underwent the operation, only the second operation ever performed on a human. Faucette’s heart disease and underlying medical conditions made him unsuitable for a traditional human heart transplant.
“The doctors caring for him believe his heart function is excellent,” said Dr. Bartley Griffith, director of the heart and lung transplant program at the University of Maryland School of Medicine, who performed the surgery.
“We currently have no evidence of infection and no evidence of rejection.”
Dr. Muhammad Mohiuddin, director of UMMC’s cardiac xenotransplantation program, said in an update released Friday: “We are withdrawing all medications that originally supported his heart. Now his heart does everything on its own.”
Mohiuddin said the focus now is on ensuring Faucette has the strength to carry out routine tasks.
“We are working very hard with our physiotherapy team who are devoting a lot of time to helping him regain the strength he lost during the last month of his hospital stay,” Mohiuddin said.
In a video released by UMMC, Faucette is shown undergoing physical therapy, including cycling, to improve his leg strength. When his physical therapist, Chris Wells, reminds him to keep smiling, Faucette laughs and says, “That’s the hard part!”
When Faucette came in, “he honestly never expected to run again,” Griffith said. Although Faucette can’t stand on his own yet, he can get out of bed with minimal help, and doctors say they’re at a “tipping point.”
Griffith said it’s time to plan the next phase of Faucette’s recovery and “think about where Larry is going in terms of his next location.”
Faucette is a married father of two from Frederick, Maryland, and a 20-year Navy veteran who most recently worked as a laboratory technician at the National Institutes of Health.
In another moment shared by UMMC, Faucette is seen going over scans of his heart with his doctors. “One looks like a normal heart. And we definitely wanted that,” he says.
Faucette was first admitted to UMMC on September 14 after experiencing symptoms of heart failure. While in the hospital, his heart stopped twice and was only restored by an automatic defibrillator in his room.
“My only real hope is the pig heart, the xenotransplantation,” Faucette told the hospital in an internal interview a few days before the operation.
“We have no expectations other than the hope of more time together,” his wife Ann Faucette said at the time. “It could be as simple as sitting on the porch and drinking coffee together.”
The experimental xenotransplantation received the green light under the U.S. Food and Drug Administration’s Compassionate Use program. According to the FDA, the program is “a potential pathway for a patient with a serious or immediately life-threatening disease or condition to obtain access to an investigational medical product (drug, biologic, or medical device) for treatment outside of clinical trials.” There are no comparable or satisfactory alternative treatment options available.”
The pig heart used came from a genetically modified pig from Revivcor, a subsidiary of United Therapeutics Corporation. The pig had 10 genes altered, including three genes that were “turned off” or inactivated, to eliminate alpha-gal sugar in the pig’s blood cells, which can trigger a severe reaction in the human immune system that leads to organ rejection . An additional pig gene was modified to control pig heart growth, while six human genes were inserted into the pig genome to increase acceptance by the immune system. The FDA first approved the genetically modified pigs for potential therapeutic use and consumption in 2020.
There are currently no clinical trials using pig organs for transplants into living humans.
Doctors also treated Faucette with an experimental antibody treatment to further suppress the immune system and prevent rejection. He will continue to be monitored for signs of rejection or the development of swine viruses. The donor pig was also carefully examined for signs of viruses or pathogens.
The hospital said Faucette fully consented to the experimental treatment and was informed of all risks. In addition, he underwent a comprehensive psychiatric evaluation and discussed his case with a medical ethicist.
Mohiuddin and Griffith founded the country’s first center for cardiac xenotransplantation research and performed the first such experimental surgery on 57-year-old David Bennett in January 2022. Bennett died two months after surgery.
Although there were no signs of rejection in the first few weeks after the transplant, an autopsy concluded that Bennett ultimately died of heart failure due to “a complex array of factors,” including Bennett’s condition before surgery. Bennett had already been hospitalized and kept on a heart-lung bypass machine for six weeks before the transplant. However, a case study of the doctors published in the Lancet also found that there was evidence of swine viruses that had not previously been identified.
According to the federal government, more than 113,000 people are on the organ transplant list, including more than 3,300 people who need a heart. The group Donate Life America says 17 people die every day while waiting for a donor organ.