Dr. James Shapiro, principal investigator of the study and Director of the Clinical Islet Transplant Program at the University of Alberta in Edmonton, Canada, reports that 19 of the 36 participants continue to be free from daily insulin injections for up to one year following their last transplant. Seven patients completed the procedure with only partial islet graft function and therefore continue to require insulin injections, although on average, at lower doses than prior to the procedure. Four patients withdrew from the study prior to completion of the protocol and six others had non-functioning grafts.
"This is an important result for the future of islet transplantation," said Shapiro. "With the completion of the treatment phase of the study, we can now say with confidence that that islet transplantation works for patients with serious and unstable type 1 diabetes and that it is possible to successfully apply a single standardized protocol at many different clinical sites," said Shapiro.
In addition, the investigators report that so far, few treatment-related complications have been noted and those were generally minor. The most common side effects of the technique were mouth ulcers, neutropenia and diarrhea, none of which were life-threatening.
With nine clinical centers participating in the trial, the ITN study is the largest clinical investigation of islet transplantation to date.
"This ITN multi-center trial has demonstrated that the Edmonton Protocol for islet transplantation can be extended successfully to multiple islet transplant centers, and can be performed without life-threatening side effects," said Dr. Richard Insel, Executive Vice President for Research at the Juvenile Diabetes Research Foundation. "JDRF is committed to improving the efficacy of islet transplantation and eliminating the need for chronic immunosuppressive therapy."
Beginning in 2001, the study enrolled thirty-six patients with brittle diabetes - that is, despite their best efforts with insulin therapy and lifestyle modification, they suffered wide swings in blood glucose levels and/or frequent hypoglycemic events. The study goals were to confirm the safety and efficacy of the Edmonton Protocol; to identify issues associated with applying a single protocol for islet transplantation across multiple centers; and to provide a baseline measure of success for future studies of immune tolerance therapies in islet transplantation.
"Clearly we have achieved our primary endpoints for the study," said Shapiro. "In many ways, this is a victory for islet transplantation and reflects very highly upon all of the investigators involved."
In addition to the University of Alberta, other participating clinical sites participating in the study are located at the University of Minnesota, University of Miami, Harvard Medical School, Washington University, Pacific Northwest Research Institute, Justis-Liebig University in Giessen, Germany, San Raffaele Scientific Institute in Milan, Italy and University Hospital in Geneva, Switzerland. The study is being conducted by the Immune Tolerance Network, headquartered at the University of California, San Francisco and is jointly sponsored by the National Institute of Allergy and Infectious Diseases, the National Institute for Diabetes and Digestive and Kidney Diseases and the Juvenile Diabetes Research Foundation.
Continued monitoring of patient and islet health are now planned for up to three years, in order to assess longer term efficacy and safety of the technique.
About the Immune Tolerance Network (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 9 countries world-wide. The ITN is sponsored by the National Institute of Allergy & 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 the JDRF
JDRF was founded in 1970 by the parents of children with juvenile diabetes - a disease that strikes children suddenly, makes them insulin dependent for life, and carries the constant threat of devastating complications. Since inception, JDRF has provided more than $680 million to diabetes research worldwide. More than 80 percent of JDRF's expenditures directly support research and education about research. JDRF's mission is constant: to find a cure for diabetes and its complications through the support of research. For more information please visit www.jdrf.org.