Two U.S. biotech companies, United Therapeutics and eGenesis, have received clearance from the Food and Drug Administration (FDA) to conduct clinical trials of gene-edited pig kidneys for human transplants. The groundbreaking approval marks a critical step in efforts to address the severe organ shortage in the United States, where over 100,000 people await transplants, including more than 90,000 in need of kidneys.
United Therapeutics, which announced its FDA approval, plans to enroll six patients with end-stage renal disease in its initial trial, with the first transplant expected by mid-2025. The trial could eventually expand to 50 participants. Leigh Peterson, the company’s executive vice president, called the authorization a “significant step forward in our relentless mission to expand the availability of transplantable organs.”
eGenesis, another leading player in xenotransplantation, revealed it had received FDA approval in December for a separate trial involving three patients with kidney failure. The study focuses on individuals who are unlikely to receive a deceased donor kidney within five years.
Xenotransplantation, or the transplantation of organs from one species to another, has long been a goal of medical science. While early experiments using primates were largely unsuccessful, recent advancements in gene editing and immune management have brought the field closer to viability. Pigs are considered ideal donors due to their rapid growth, large litters, and established role in the human food supply.
United Therapeutics stated that trial participants will be monitored for life to assess kidney function, survival rates, and the risk of zoonotic infections, which are diseases that can jump from animals to humans.
Currently, the only living human recipient of a pig organ is Towana Looney, a 53-year-old from Alabama, who received a United Therapeutics pig kidney on November 25, 2024. Looney has now survived 71 days with the organ, making her the longest-living recipient of a pig organ. By comparison, David Bennett of Maryland received a pig heart in 2022 and survived 60 days. Both cases underscore the potential of xenotransplantation as a transformative solution to organ shortages.