Kent Peterson, senior editor, has also produced award-winning work in television and radio.

Promising research suggests a revolutionary way to treat type 1 diabetes may have been right under our noses for the past 100 years.

An inexpensive, generic medication long used as a tuberculosis vaccine may prevent and even reverse type 1 diabetes and other autoimmune diseases including multiple sclerosis.

“It is incredible that a safe and inexpensive vaccine may be the key to stopping these terrible diseases,” said the trial’s principal investigator Denise Faustman, MD, PhD, and director of the Massachusetts General Hospital Immunology Laboratory, where the latest in a series of studies is underway.

How it works

The bacillus Calmette-Guerin vaccine (BCG) works at the genetic level to prevent the body from forming abnormal white blood cells that mistakenly attack insulin-secreting cells in the pancreas, causing type 1 diabetes. BCG appears to activate and regulate other cells called Tregs that can stop the unwanted attack. Faustman describes the effect as “resetting the immune system to halt the underlying cause of the disease.”

A phase 1 trial in people with type 1 diabetes showed temporary improvements in subjects who were given two injections of BCG four weeks apart. Many began to produce modest amounts of insulin.

In the current phase 2 study, 150 people will receive one additional injection per year for four years to see if normal blood sugar levels can be achieved and maintained. Interim findings were recently presented at the 77th Scientific Sessions of the American Diabetes Association. After two years, the early results are encouraging.

A new use for an old vaccine

During the past century, BCG has been administered four billion times in countries around the world. Because the vaccine has been so widely used for so long, its safety is well proven. Since it is available in generic form, there are no high costs typically associated with breakthrough drugs. Children in the United States aren’t given BCG with their routine immunizations, though, because tuberculosis is no longer common here.

Other groups are also investigating BCG’s potential to reverse harmful autoimmune responses in the body. While people with type 1 diabetes have long hoped for a way to prevent and reverse the disease, it will be years before we know whether BCG lives up to researchers’ expectations.