For the second time ever, U.S. surgeons have transplanted a genetically modified pig heart into a Navy veteran in a last-ditch effort to save his life.
The surgery was performed at the University of Maryland Medical Center on Sept. 20 on a 58-year-old patient, transplanting a genetically modified pig heart.
The patient, Lawrence Faucette, had end-stage heart disease. He was deemed ineligible for a traditional transplant with a human heart by UMMC and several other leading transplant hospitals due to his pre-existing peripheral vascular disease and complications with internal bleeding.
This transplant was the only option for Faucette, who was facing near-certain death from heart failure. The patient, who lives in Frederick, MD, is a married father of two and a 20-year Navy veteran and most recently worked as a lab technician at the National Institutes of Health before his retirement.
“He is recovering well and communicating with his loved ones,” reported the UMMS in a press release on Friday. “He is currently breathing independently, and his heart functions well without assistance from supportive devices.”
This is only the second time in the world that a genetically modified pig heart has been transplanted into a living patient. Both historic surgeries were performed by the University of Maryland School of Medicine faculty at the University of Maryland Medical Center.
The first historic surgery, performed in January 2022, was conducted on David Bennett by University of Maryland Medicine surgeons (comprising UMSOM and UMMC), who are recognized as the leaders in cardiac xenotransplantation.
“My only real hope left is to go with the pig heart, the xenotransplant,” said Mr. Faucette during an interview from his hospital room a few days before his surgery. “Dr. Griffith, Dr. Mohiuddin, and their entire staff have been incredible, but nobody knows from this point forward. At least now I have hope, and I have a chance.”
Faucette’s wife, Ann, noted, “We have no expectations other than hoping for more time together. That could be as simple as sitting on the front porch and having coffee together.”
The U.S. Food and Drug Administration granted emergency approval for the surgery on Friday, September 15, through its single patient investigational new drug “compassionate use” pathway. This approval process is used when an experimental medical product, in this case, the genetically modified pig’s heart, is the only option available for a patient with a severe or life-threatening medical condition. The approval was granted in the hope of saving the patient’s life.
“We are once again offering a dying patient a shot at a longer life, and we are incredibly grateful to Mr. Faucette for his bravery and willingness to help advance our knowledge of this field,” said Bartley P. Griffith, MD, who surgically transplanted the pig heart into the second patient as well as the first patient to receive this groundbreaking surgery at UMMC. Dr. Griffith is the Thomas E. and Alice Marie Hales Distinguished Professor in Transplant Surgery and Clinical Director of the Cardiac Xenotransplantation Program at UMSOM. “We are hopeful that he will get home soon to enjoy more time with his wife and the rest of his loving family.”
About 110,000 Americans are currently waiting for an organ transplant, and more than 6,000 patients die each year before getting one, according to the federal government’s organdonor.gov.
Transplanting animal organs (known as xenotransplantation) could potentially save thousands of lives but carries unique risks. Besides the fear of transmitting an unknown pathogen from animal to human, xenotransplants are more likely to trigger a dangerous immune response. These responses can trigger an immediate organ rejection with a potentially deadly outcome for the patient.
Three genes — responsible for a rapid antibody-mediated rejection of pig organs by humans — were “knocked out” in the donor pig. Six human genes responsible for the immune acceptance of the pig heart were inserted into the genome. One additional gene in the pig was knocked out to prevent excessive growth of the pig heart tissue, for a total of ten unique gene edits made in the donor pig.
United Therapeutics Corporation, through its xenotransplantation subsidiary Revivicor, based in Blacksburg, VA, provided the genetically modified pig to the xenotransplantation laboratory at UMSOM. On the morning of the transplant surgery, the surgical team, led by Dr. Griffith and Dr. Mohiuddin, removed the pig’s heart and placed it in the XVIVO Heart Box, a machine perfusion device, to keep it until surgery.
The physician-scientists are also treating the patient with a novel antibody therapy and conventional anti-rejection drugs designed to suppress the immune system and prevent the body from damaging or rejecting the foreign organ. The novel therapy being developed by Eledon Pharmaceuticals is an experimental antibody called tegoprubart which blocks CD154, a protein involved in immune system activation.
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