Roche Diagnostics Products Contribute to Success of ITN Multicenter Islet Transplant Trial

Indianapolis, IN. -- On June 2, 2003 the Immune Tolerance Network (ITN), a collaborative scientific and research organization 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 LiberaseÔ 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, provided the following comments about islet transplantation and Roche Diagnostics' contribution to the success of that technology:

"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, standardized 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. Their willingness to work so closely with multiple investigators worldwide, and to continually refine their product to meet individualized specifications is a huge tribute to their team spirit and determination to support islet transplantation."

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.

"Roche Diagnostics enthusiastically supports this trial and applauds its encouraging results. We are proud to have played an important role in the development of LiberaseÔ enzyme, a critical reagent in this groundbreaking trial. Our participation in these clinical trials is further evidence of our commitment to diabetes care and the vision we have for continuous monitoring and an automated pancreas," said Martin Madaus, President and CEO, Roche Diagnostics Corporation, North America. "Whether it's an Accu-ChekÒ blood glucose monitor which helps those living with diabetes manage their disease more easily, or a purified enzyme that helps make islet transplantation a clinical reality, Roche is dedicated to working with the ITN and others to push the limits in finding the best approaches to treat or cure diabetes."

Roche Diagnostics Diabetes Care business area is the world's leading company in diabetes monitoring systems and services with its Accu-ChekÒ blood glucose monitors, and is committed to making life better for those living with diabetes. Roche's technological support of the ITN islet transplant trial demonstrates Roche's commitment to diabetes care and brings the vision of a curative therapy closer to reality.

For more information about the ITN Islet Transplantation Research and the Edmonton Protocol, please visit: http://www.immunetolerance.org/public/clinical/islet/.

About Roche and Roche Diagnostics
Headquartered in Basel, Switzerland, Roche is one of the world's leading innovation-driven healthcare groups. Its core businesses are pharmaceuticals and diagnostics. Roche is number one in the global diagnostics market, the leading supplier of pharmaceuticals for cancer and a leader in virology and transplantation. As a supplier of products and services for the prevention, diagnosis and treatment of disease, the Group contributes on a broad range of fronts to improving people's health and quality of life. Roche employs roughly 62,000 people in 150 countries. The Group has alliances and research and development agreements with numerous partners, including majority ownership interests in Genentech and Chugai. Roche's Diagnostics Division, the world leader in in-vitro diagnostics with a uniquely broad product portfolio, supplies a wide array of innovative testing products and services to researchers, physicians, patients, hospitals and laboratories world-wide. For further information, please visit our websites www.roche.com and www.roche-diagnostics.com.

About the ITN
The Immune Tolerance Network is an international research consortium that aims to accelerate the clinical development of immune tolerance therapies for use in transplantation, autoimmune diseases and allergy and asthma. Headquartered at the University of California San Francisco, the ITN is comprised of over 80 leading physicians and scientists from over 40 institutions in nine countries worldwide. The ITN is sponsored by the National Institute of Allergy and Infectious Diseases, with additional funds provided by the National Institute of Diabetes and Digestive and Kidney Diseases and the Juvenile Diabetes Research Foundation. Additional information on the Immune Tolerance Network may be found at www.immunetolerance.org.

About Zenapax
Zenapax is an immunosuppressive humanized monoclonal antibody or "anti-rejection" drug approved by the FDA in December 1997 to be used in combination with other immunosuppressive drugs (cyclosporine and corticosteroids) to prevent acute organ rejection in kidney transplant patients. The recommended dose of Zenapax is 1.0 mg/kg. Based on clinical trials, the standard course of Zenapax therapy is five doses.The most frequently reported adverse events associated with Zenapax were constipation, nausea, diarrhea and vomiting. Cellulitis and wound infections occurred more frequently in patients treated with Zenapax versus placebo. Severe hypersensitivity reactions following Zenapax administration have been reported rarely. Only physicians experienced in immunosuppressive therapy and management of organ transplant patients should prescribe Zenapax (daclizumab). The physician responsible for Zenapax administration should have complete information requisite for the follow-up of the patient. Zenapax should only be administered by healthcare personnel trained in the administration of the drug who have available adequate laboratory and supportive medical resources. For full prescribing information, visit www.rocheusa.com/products/zenapax/pi.html.