NZSSD Executive Position Statement on Xenostransplantation in Type 1 Diabetes

The Constitution of the New Zealand Society for the Study of Diabetes includes the following three objectives:

  1. To advance and foster the study of diabetes in New Zealand and Oceania
  2. To encourage, support and enable high quality research in all aspects of diabetes
  3. Provide a national source of scientific and clinical expertise, reference and advocacy for:
    a. The condition of diabetes mellitus, its prevention and its complications
    b. The care of people with diabetes

Xenotransplantation offers a potentially important therapeutic option for people with Type 1 diabetes. Thus, in keeping with its objectives, the NZSSD Executive considers that the Society should express an opinion regarding the proposed xenotransplantation trials.

NZSSD is, in principle, supportive of future xenotransplantation clinical trials in humans with Type 1 diabetes in New Zealand on the following basis:

  • That members of NZSSD who provide specialist care for people with diabetes have the opportunity to comment on the proposed clinical trial.
  • That reproducible pre-clinical non-human studies indicate that the procedure is associated with significant expectation of benefit. *
  • That this expectation of benefit is deemed to significantly exceed any potential risk/s.
  • That appropriate independent regulatory oversight of such clinical trials is in place.

*  The NZSSD Executive support the International Xenotransplantation Association (IXA) [1] interim recommendations regarding preclinical data necessary to support an application for clinical islet xenotransplantation. This is as follows:

"With respect to efficacy in preclinical studies, IXA would support a clinical trial if at least 5 of 10 consecutive primate recipients of islet xenografts are normoglycemic (documented at least weekly) and exogenous insulin-free for 6 months post-transplant, and if at least 2 remain insulin independent for 12 months on a clinically applicable immunotherapeutic protocol. For the example of porcine islet grafts in primates, islet function should be documented intermittently by 1) demonstration of circulating PORCINE insulin or C-peptide with pig-specific tests (by specific ELISA or HPLC), 2) demonstration of minimal or absent PRIMATE insulin or C-peptide (by specific ELISA or HPLC) both under fasting conditions and in response to glucose challenge, and 3) glycosylated hemoglobin (HgbA1c) <7.5%. Insulin-free survival can be achieved in primates after porcine islet cell transplantation. The IXA strongly recommends that efficacy sufficient to proceed to clinical investigation should be defined as primate survival dependent on the islet xenograft, without requirement of exogenous insulin. IXA does not preclude the possibility that future scientific development may permit alternative evidence to be presented to justify progress to a human clinical trial, such evidence should be submitted to thorough peer-review and informed public consideration." [2]

 

[1] See: http://www.transplantation-soc.org/sections.php?s=01

[2] Source: http://www.transplantation-soc.org/downloads/IXA-Islet-guidance-2-17-08.pdf