Liver Xenotransplantation: Ethical and Societal Implications.

The shortage of transplantable livers and high waitlist mortality rates have accelerated the clinical translation of liver xenotransplantation. Recent milestones, including extracorporeal perfusion models and gene-edited pig-to-human transplants in both decedents and living patients, indicate that clinical trials may be imminent. While the ethics of solid organ xenotransplantation generally-such as animal welfare, xenozoonosis, and informed consent-have been debated, the specific implications of liver xenotransplantation remain underexplored. This article examines these unique challenges. We argue that pediatric liver xenotransplantation research might proceed simultaneously with adult research due to high waitlist mortality among infants. In adults, we analyze how liver xenotransplantation intersects with historical controversies regarding patient selection, specifically concerning alcohol-associated liver disease and hepatocellular carcinoma. We explore the ethical risks of a potential dual pathway allocation system that could bifurcate waitlists based on disease etiology, raising concerns regarding distributive justice and the stigmatization of addiction. Finally, we consider whether xenografts might serve as a trial of time for patients currently ineligible for allotransplantation.