A New Zealand trial in which pig cells will be transplanted into diabetes patients will be peer reviewed by a top international researcher to ensure there are proper controls.
The trial - to begin early next year - was approved last month on the condition that it received a favourable review.
The researcher, who is based overseas, will advise whether additional controls are needed.
It is hoped the trial, by a xenotransplantation company, Living Cell Technologies, will help stimulate insulin production in eight type-one diabetes patients.
The National Health Committee has already imposed a set of strict conditions, but the review, which begins on 5 December, will look at whether they are sufficient.