A new promising vaccine designed to reverse Type-1 diabetes has now been approved for a phase II clinical trial by the U.S. Food and Drug Administration. The vaccine, known as Bacillus Calmette-Guerin (BCG) has already been found in earlier trials to be effective in reversing advanced Type-1 diabetes in mice, and has since completed another successful phase of human clinical trials.

The next phase of trials is expected to last for five years and will investigate whether repeat BCG vaccinations can clinically improve Type-1 diabetes in adults between the ages of 18 and 60 years, who have small but still detectable levels of insulin secretion from the pancreas.

"In the phase I clinical trial we demonstrated a statistically significant response to BCG, but our goal in phase II is to create a lasting therapeutic response," said principal investigator of the study Denise Faustman, director of the Massachusetts General Hospital (MGH) immunobiology laboratory.

"We will be working again with people who have had type-1 diabetes for many years. This is not a prevention trial; instead, we are trying to create a regimen that will treat even advanced disease."

BCG, however, is not a new drug on the market. In fact, this generic drug has over 90 years of clinical use and safety data. Currently, the drug is approved by the FDA to be used as a vaccination against tuberculosis and for the treatment of bladder cancer. The vaccine is already known to elevate levels of the immune modulator tumor necrosis factor (TNF), which researchers have already shown can temporarily eliminate in both humans and mice the abnormal white blood cells responsible for autoimmune Type-1 diabetes.

This latest trial will be conducted at Massachusetts General Hospital and will follow 150 adults with long term Type-1 diabetes. For the trial, the patients will be randomized and will receive two injections four weeks apart of either BCG or the placebo and then a single injection annually for the next four years. Researchers hope that the effectiveness of BCG will be able to be ascertained over this extended period of time. If the drug proves effective, it could be life changing for many adults suffering from the long term effects of life with Type-1 diabetes.

Faustman and her colleagues made the announcement of this next phase of clinical trials for the drug at the 75th Scientific Sessions of the American Diabetes Association in Boston, Massachusetts.