Animal into human

Xenotransplantation, animal to human, defined as living cells, tissues or organs of animal origin and human body fluids, cells, tissues or organs that have ex vivo with these living, xenogeneic materials, has the potential to constitute an alternative to material of human origin and bridge the shortfall in human material for transplantation.

Hopes and risks, research and precaution

However, xenogeneic transplantation carries risks, in particular of transmission of known or as yet unrecognized xenogeneic infectious agents from animals to human beings and from recipients of xenogeneic transplants to their contacts and the public at large.

Xenogeneic transplantation is a topic for research and clinical trials. However, xenogeneic transplantations are carried out in some countries as unregulated traditional and non-evidence-based treatment. International collaboration and coordination for the prevention and surveillance of infections resulting from xenogeneic transplantation is mandated.

Statements for health authorities on xenotransplantation

The World Health Assembly Resolution WHA57.18 (2004) urges Member States to ensure effective national regulatory control and surveillance mechanisms before allowing xenogeneic transplantation to take place. The attached statement for health authorities results from an informal expert advisory consultation held at WHO in April 2005.

Prerequisite for Clinical Trials of Xenotransplantation

The "First WHO Global Consultation on Regulatory Requirements for Xenotransplantation Clinical Trials" , organized in collaboration with the Ministry of Health of China and the International Xenotransplantation Association, was held in Changsha, China, from 19-21 November 2008. It brought together 52 participants, experts and representatives of health authorities from all regions of the world. The "Changsha Communiqué" (downloadable below) summarizes the outcomes of this Consultation

The “Second WHO Global Consultation on Regulatory Requirements for Xenotransplantation Clinical Trials”, held in October 2011 in Geneva, provides further guidance insisting in particular on the need for transparency and external assessment of protocol, of their implementation and outcomes.

Related documents


Contact information

Transplantation of human cells, tissues and organs
Service Delivery and Safety
Health Systems and Innovation
World Health Organization
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