The International Human Xenotransplantation Inventory: Current Data and Future Directions

Abstract

The global demand for organ transplantation outpaces supply, necessitating innovative solutions. Xenotransplantation, using animal organs, cells, and tissues, is a promising solution to address the organ shortage. The World Health Organization and the International Xenotransplantation Association collaboratively established an online inventory in 2006 ( www.humanxenotransplant.org ) to catalog human xenotransplantation practices. The inventory, managed successively by the Geneva University Hospital and the Sichuan Provincial People's Hospital, aligns with the World Health Organization directives for transparency and best practices in the field of transplantation. Relevant data have been regularly collected from numerous sources (scientific publications, congresses, press articles, and declarations of International Xenotransplantation Association members) by a dedicated team in Switzerland and China, ensuring rigorous verification. The initial information is used to create a first entry in the database, which is then completed when more details become available. As of May 2024, the inventory contained 54 entries of distinct xenotransplantation procedures undertaken on humans. From these data, various trends can be observed over the past 2 decades regarding the type of transplantation, their regulation status, and the source animal. Notably, recent high-profile cases of solid organ transplantation involving kidneys and hearts were made feasible through years of progressive xenotransplantation research and ongoing changes to regulations. Recent clinical applications of solid organ xenotransplantation suggest that more clinical procedures may soon follow for patients with end-stage kidney or heart disease or diabetes. Future perspectives advocate for increased funding and expansion of the current registry or its potential integration into a larger and more broadly internationally recognized registry, such as the Global Observatory on Donation and Transplantation.

FIGURE 1.

Type of transplantation, by year, from 1990 to 2024. The asterisk outlines a case of heart xenotransplantation unofficially conducted in India (see the text).

FIGURE 2.

Practices undertaken, by year, from 1990 to 2024, indicate the regulatory status of the jurisdiction when and where the case was undertaken.

FIGURE 3.

Main source of information, by year, from 1990 to 2024. Publication refers to peer-reviewed scientific articles, and Congress also includes other academic conferences, etc.

FIGURE 4.

Source animal, by year, from 1990 to 2024. A few cases involved multiple different source animals, hence the increased total number in comparison with other figures.