The trial was designed to test the effectiveness of islet cell infusions in stabilising the blood sugar levels of patients with ‘brittle’ type-1 diabetes. These patients have poor glycaemic control and often cannot tell when they are hypoglycaemic.
The trial involved 36 patients aged 18–65 who had had type-1 diabetes for at least five years and who had reduced awareness of hypoglycaemic episodes or severe glycaemic lability.
The patients were treated at one of nine international centres using the Edmonton protocol. This involved up to three infusions of islet cells taken from the pancreases of brain dead donors until the patient was able to produce their own insulin.
The patients were then followed up over three years and their insulin production levels and glycaemic control monitored.
One year after the final infusion, 44 per cent of patients were still producing enough insulin that they had no need for insulin injections. Another 28 per cent had some residual islet function.
Although three quarters of those who initially reached ins-ulin independence were dependent on insulin again two years after the transplant, their glycaemic control was much improved. They no longer suffered hypoglycaemic episodes or severe glycaemic lability.
Lead researcher Professor James Shapiro, from the Univ-ersity of Alberta in Canada, said the most important finding was that even patients who continued to need insulin showed real improvement after the transplant.
‘This isn’t an all-or-nothing procedure. Even partial survival of the transplanted islets can lead to significantly improved health in these patients.
‘This really shows that islet transplantation can be tremendously successful in protecting against hypoglycaemic unawareness,’ he said.