KEY POINTS:
Pig cells have been successfully transplanted into the first patient in new human trials of a revolutionary diabetes therapy pioneered in south Auckland.
The 26-year-old man, who has had type 1 diabetes for at least 10 years, had the transplant in Russia last Thursday.
He is said to be doing well after the clusters of insulin-producing cells from the pancreases of neo-natal piglets were inserted into his abdomen.
The cells were encapsulated in a special gel to protect them from the human immune system.
Melbourne-based Paris Brooke, general manager of Australian stock exchange-listed Living Cell Technologies, which makes the therapy in New Zealand, said today it was not yet known if the patient's need for insulin injections had been affected.
"That will take a little while. It takes a while for the cells to bed down in the system. We won't expect to see those types of effects for quite a few weeks and then that will be monitored over the period of the trial as well, but we certainly expect to see a reduction in insulin requirements for sure," Brooke said.
Living Cell hopes to commercialise the type 1 diabetes therapy for general use by 2012.
Type-1 diabetes affects about 11,000 New Zealanders. It usually starts in childhood and leaves people unable to produce insulin, a substance the body uses to process glucose. They need regular injections of synthetic insulin.
Living Cell's medical director, Professor Bob Elliott, who developed the therapy, said the plans for a New Zealand trial at Middlemore Hospital in south Auckland were proceeding well. He expected it would start in November or December.
The Health Ministry's Medsafe unit had approved the New Zealand trial, but it was still in front of a regional ministry ethics committee and after that required final sign-off by Health Minister Pete Hodgson.
The Russian trial, at the Sklifasovsky Institute in Moscow, which has extensive experience in organ transplantation and xenotransplantation (animal-to-human transplants), is being overseen by a Boston-based medical research company to ensure it adheres to international regulatory standards.
The capsules containing the pig cells are the size of a pinhead and each of the six adults in the Russian trial will receive billions of the cells. The encapsulation avoids the need for anti-rejection drugs, but still allows the pig cells to respond to the patient's insulin needs, releasing the substance as required.
The patients will receive two low doses of the cells every six months for a year, followed by a further year of study of the therapy's therapeutic effect. In this trial, patients are given the lowest clinically-effective dose to demonstrate safety. The dosing is repeated for extra clinical benefit.
The trials are effectively a continuation of an Auckland trial halted in 1996, although the therapy has been improved.
The 1996 trial was stopped after six patients were treated because new research suggested pig-cell xenotransplants could allow pig retroviruses to jump to the human population, but Living Cell, which has tested the therapy on animals, says there is no evidence of humans or other animals being infected by the viruses.
