Xenotransplantation Research Warning
An unsolicited letter of concern about New Zealand xenotransplantation research sent by an international expert group to the Minister of Health has been referred to the Parliamentary Select Committee considering a law change on the issue.
The letter, by the International Xenotransplantation Association, relates to concerns about human trials of pig pancreatic islet tissue transplants in Mexico and proposed trials in the Cook Islands by New Zealand company Diatranz Ltd.
The letter, released today by the Ministry of Health, sets out the following concerns: · there is a risk of transmission to humans of pig endogenous retrovirus, which is small, but not zero, and that is not the only infectious agent. · studies on benefits to the patient are inadequate and do not counterbalance the potential risks involved · demonstration of the effectiveness of the treatment in studies performed in non-human primates is required before human trials are justified · the risks can only be regarded as manageable if proper monitoring of the recipients and family contacts can be undertaken on a long term basis · jurisdictions like Mexico and Cook Islands do not have appropriate regulatory authorities to develop and maintain appropriate guidelines do safeguard the patients and their contacts.
Ministry of Health Chief Advisor Regulation and Safety, Dr Bob Boyd said the Association has a keen interest in the success of transplantation, so they would not lightly write of their concerns unless they believed the Diatranz Ltd trials posed a risk to the ultimate successful adoption of xenotransplantation as a treatment.
Dr Boyd said there needs to be substantially more informed debate than there has been to date, and it should involve wider views than those who stand to benefit if the research leads to future benefit for diabetics.
The proposed amendment to the Medicines Act currently before Parliament does not call for a ban on innovations in treatment, but puts an onus on the Minister of Health to be satisfied that these issues have been adequately addressed before the go-ahead is given.
The full text of the letter to the Minister of Health is set out below. It is supported by a copy of a letter the Council of the International Xenotranplantation Association drafted and sent to the medical journals about transplantation after they heard Dr Elliott of Diatranz Ltd's presentation on the company's current trial underway in Mexico.
Hon. Annette King Minister of Health New Zealand
On behalf of the International Xenotransplantation Association (IXA) of which I am President Elect, I wish to express the deep concern of our Association about the recent activities of a New Zealand company Diatranz Ltd. in conducting human trials of pig pancreatic islet tissue transplants in Mexico and their proposal to conduct further trials in the Cook Islands. May I first say that IXA is an international association of several hundred members for most developed countries who are interested in seeing xenotransplantation become a successful clinical treatment for organ failure.
I attach a copy of a statement that was recently made by our association in response to the Mexico trials. The statement is to be published in the scientific journals Transplantation and Xenotransplantation. These concerns apply even more forcefully to the proposed trials in the Cook Islands.
Our concerns are as follows: 1. Xenotransplantation of pig cells, tissues or organs to humans presents risks of infections from the pigs spreading into the human population. You will have heard of pig endogenous retrovirus (PERV). The potential of this virus to infect the human recipients and possibly spread to other humans is one of the risks. The risk is probably small but is not zero. This risk has to be weighed against the possible benefit to the recipients. It is our opinion that the studies of possible benefit are inadequate and do not counterbalance the potential risks involved. Demonstration of effectiveness of the treatment in studies performed in non-human primates is required before human trials are justified. 2. The risks can only be regarded as manageable if proper monitoring of recipients and family contacts can be undertaken on a long term basis. It should be emphasised that PERV are not the only infectious agents of concern. Further, I can not imagine that the Cook Islands have the sophisticated virology facilities needed for monitoring for pig viruses, bacteria etc which might infect humans. 3. Jurisdictions like Mexico and the Cook Islands do not have appropriate regulatory authorities to develop appropriate guidelines to safeguard the patients and their contacts. One suspects that the reason that trials are conducted in such countries is precisely because they do not have such safeguards.
I would be grateful if you would consider these views when considering this contentious issue.
Professor Anthony JF d'Apice
Immunology Research Centre
St Vincent's Hospital
PO Box 2900 Fitzroy
Vic., 3065, Australia