Hope for Type I diabetes sufferers

Immune Tolerance Network (ITN), a collaborative scientific and research organisation aiming to accelerate the clinical development of new tolerance therapeutics in human disease, announced preliminary results from its 36-patient multicenter clinical trial of the Edmonton Protocol for human islet transplantation.

This trial targets people with unstable Type 1 diabetes. Roche Diagnostics participated in the trial through the manufacture of Roche's Liberase HI Enzyme, a purified collagenase preparation that was specifically developed for the isolation of human islets for transplantation.

Human islet transplantation is one of the few curative approaches to Type I diabetes under development today. Recent success suggests that it may be an effective treatment for persons with unstable diabetes and protect against the serious secondary complications associated with the disease. It is expected that success in human islet transplantation will lead to improvements in other curative, cell-based approaches, such as xenotransplantation and stem cell therapy, which could treat a larger number of persons with diabetes.

Dr James Shapiro, director of the Clinical Islet Transplant Program in Edmonton, Alberta, Canada, and principal investigator of the ITN Multicenter Islet Transplant Trial said: 'These are exciting times in islet transplantation, as this therapy moves one large step forward from research to standard practice of medicine. In its current form, islet transplant will only be suitable for highly selected patients with the most brittle forms of type 1 diabetes. As the treatment develops however, we anticipate the day that it will be more widely available to a larger population of diabetes sufferers.' The early results of the international multicenter trial have shown us that the Edmonton Protocol and more recent protocol variants can work extremely well and provide us with much of the knowledge required for more widespread implementation of the technique.

'Roche Diagnostics has been integral to the success of this remarkable therapy. The development of low endotoxin, standardised lots of Liberase enzyme has made one of the biggest differences to our ability to transplant islets. Before this enzyme, we had far less success at making islets. Roche is to be congratulated in facilitating the transition from art to science in the islet extraction process.'

For nearly 20 years, Roche Diagnostics has been involved in the development and manufacturing of purified enzymes for human islet isolation.

Roche researchers were trained in islet isolation at several of the clinical centers that participate in the ITN study, and developed the Liberase HI enzyme as a result of that training. Roche Pharmaceuticals' Zenapax (daclizumab), an immunosuppressive medication indicated in the prophylaxis of acute organ rejection in patients receiving kidney transplants, also was used in the ITN trial.