Australian scientists at the Walter & Eliza Hall Institute of Medical Research in Melbourne have developed a potential vaccine for type 1 diabetes.

The results of a successful phase II human clinical trial have shown that a nasal insulin spray can protect children at high risk of developing type 1 diabetes, preventing them from developing the potentially fatal disease for at least five years.

The success is expected to have global implications, with the incidence of type 1 diabetes increasing by at least 37% over the last decade.

Type 1 Diabetes

More than 140,000 Australians have type 1 diabetes, which is the most serious form of diabetes. Unpreventable and incurable, it occurs when the body's immune system mistakenly turns on its own cells, killing the insulin-producing beta cells in the pancreas, and removing the body's ability to make insulin.

Sufferers are dependent on multiple daily injections of insulin to survive. They are at risk of developing devastating complications including heart disease, kidney failure, blindness, nerve damage and amputation.

The Trial

A team lead by Professor Len Harrison conducted the phase II trial at The Royal Melbourne Hospital in children at high risk of developing type 1 diabetes. Of the 38 children in the trial, 12 who started with very little or no insulin-producing function went on to develop diabetes within one to two years. However, of the other 26, all of whom began the trial with some of their own insulin-producing function, none developed diabetes after three years.

Professor Harrison said the first clinical human trials had followed more than 10 years' successful work in mouse models with type 1 diabetes.

Commenting on the trial, Professor Harrison said, "The vaccine teaches the immune system to protect the insulin-producing cells in the pancreas, rather than attack them and trigger the development of type 1 diabetes. The results from the trial are very encouraging. First, the use of nasal insulin has been established as being safe. Second, we found that nasal insulin issued protective instructions to the immune system in humans, as we found in the mice that were protected from diabetes by this treatment. The hope is that these instructions will stop the self-destructive process in people at risk of developing type 1 diabetes."

The nasal insulin trial was conducted with the support of the Juvenile Diabetes Research Foundation and the NHMRC. The findings of the nasal insulin trial are published in Diabetes Care, a journal of the American Diabetes Association, vol 27, no 10, October 2004.

Next Steps

A trial in adults has almost been completed. Prof Harrison and his team are in final preparations for a third trial in a larger group of at-risk children and young adults. The trial will use several doses of nasal insulin to determine the best outcome. Between 12,000 and 20,000 people at risk of type 1 diabetes will be screened to find at least 200 with antibodies present, to participate in the five-year trial. "At-risk" children are those who have a first degree relative with type 1 diabetes.

The Juvenile Diabetes Research Foundation is the world's largest not-for-profit supporter of diabetes research, investing over US$100 million in the search to find a cure for type 1 diabetes each year. JDRF was founded in the US in 1970 by parents of children with type 1 diabetes, a disease which strikes people suddenly, makes them dependent on multiple daily injections of insulin to survive and at risk of devastating health complications like blindness, kidney failure, heart disease and amputation.


For further information:

Karolyn Andrews, Media & PR Manager, JDRF
Ph. 02 9966 0400 (x203) or 0403 787 077 | email: kandrews@jdrf.org.au