University of Maryland Medical Center (UMMC) has successfully performed the world’s second pig heart transplant, bringing hope to patients with terminal heart disease. The groundbreaking surgery, which took place on September 20, involved the transplantation of a genetically-modified pig heart into a 58-year-old patient. This patient, Lawrence Faucette, had end-stage heart disease and was ineligible for a traditional heart transplant due to complications with internal bleeding and peripheral vascular disease.
The historic surgery was performed by the team of surgeons at the University of Maryland School of Medicine (UMSOM) faculty, who are recognized as leaders in cardiac xenotransplantation. The first successful pig heart transplant was also performed by this team in January 2022 on David Bennett. Both surgeries have been performed at UMMC.
Mr. Faucette, a retired lab technician at the National Institutes of Health and a 20-year Navy veteran, was facing near-certain death from heart failure. The pig heart transplant was his only option, and he expressed hope and gratitude for the opportunity. His wife, Ann Faucette, shared their simple hope of having more time together.
The genetically modified pig hearts used in the transplants are the result of extensive research in xenotransplantation. Physiological similarities between pigs and humans make pig organs ideal for transplantation. Three genes that cause rapid rejection of pig organs were knocked out in the donor pig, and six human genes responsible for immune acceptance were inserted. An additional gene was also knocked out to prevent excessive growth of the pig heart tissue. In total, 10 unique gene edits were made in the donor pig.
The transplant surgery was made possible through emergency approval from the U.S. Food and Drug Administration (FDA) under its single patient investigational new drug compassionate use pathway. The FDA granted this approval in the hope of saving Mr. Faucette’s life. The surgical team, led by Dr. Griffith and Dr. Mohiuddin, removed the pig’s heart and preserved it in a machine perfusion device until the transplant surgery.
Although xenotransplantation holds the potential to save thousands of lives, it comes with unique risks such as transmitting unknown pathogens and triggering dangerous immune responses. To mitigate these risks, the patient is being treated with a novel antibody therapy, along with conventional anti-rejection drugs. The antibody therapy, developed by Eledon Pharmaceuticals, blocks a protein involved in immune system activation.
The successful second pig heart transplant is a significant milestone in the advancement of xenotransplantation. The researchers at UMSOM and United Therapeutics Corporation, through its subsidiary Revivicor, have dedicated years of research and gene editing to bring this lifesaving procedure closer to clinical trials. Their efforts provide hope to the 110,000 Americans currently on the organ transplant waiting list.
