This new form of treatment might benefit millions

EDITOR—Fano has written a response in the eBMJ (and published here, the third letter) commenting on Vanderpool's article on xenotransplantation.1 2 He advocates a ban on xenotransplantation, largely on the grounds of the risk of the transfer of infection. Cells taken from carefully screened pigs have been used in the treatment of patients with diabetes, certain neurological diseases, and liver failure. There has been no definite evidence of the transfer of a porcine infection to human recipients.

Nevertheless, as with almost every medical or scientific advance, it will be impossible to exclude all risk, even if this is related only to hitherto unknown pig bacteria or viruses. The ultimate decision whether to use any new therapeutic agent or procedure rests on an assessment of the risk to benefit ratio. As the potential benefits to individuals or society increase, the acceptance of slightly increased risk becomes warranted. We must not reduce our obligation to take all possible steps to minimise any perceived risk to society, but we have a moral obligation to accept a small risk to the community if the new treatment leads to great benefit to many individuals in that community.

The potential benefits of xenotransplantation are immense. Many millions of people with such diverse conditions as diabetes and degenerative brain disease may have the quality of their lives vastly improved, and in those with advanced organ failure xenotransplantation will be lifesaving. In the United States over 60 000 people currently await a human donor organ but only 20 000 organs will become available this year. At least 10 people die every day while waiting. Similar figures could be quoted for other regions of the developed world.

This new form of treatment may ultimately benefit millions of patients. Rather than calling for a ban on it we suggest …