There's new hope for stopping Type 1 diabetes in its tracks after researchers discovered an existing drug can prevent the condition from developing – and the same techniques used here could also be applied to other diseases.

The drug in question is methyldopa, currently on the World Health Organisation's list of essential drugs having been used for more than 50 years to treat high blood pressure in pregnant women and children.

By running an analysis of thousands of drugs through a supercomputer, the team of researchers was able to pinpoint methyldopa as a drug able to block the DQ8 molecule. The antigen is found in a proportion of the population and has been implemented in auto immune responses.

It appears in some 60 percent of people at risk from developing Type 1 diabetes.

"This is the first personalised treatment for Type 1 diabetes prevention," says one of the team, Aaron Michels from the University of Colorado Anschutz Medical Campus. "This is very significant development."

Based on the supercomputer calculations, the scientists found that methyldopa not only blocked the binding of DQ8 but didn't harm the immune functions of other cells, which is often the case with drugs that interfere with the body's immune system.

Overall, the research covered a period of 10 years – after the supercomputer analysis, the drug was tested in mice and in 20 patients with Type 1 diabetes through a clinical trial. The new drug is taken orally, three times a day.

While it's not a full cure (work on that continues), methyldopa could help delay, or even limit the onset of Type 1 diabetes – a disease that currently starts mostly in childhood.

"We can now predict with almost 100 percent accuracy who is likely to get Type 1 diabetes," says Michels. "The goal with this drug is to delay or prevent the onset of the disease among those at risk."

That 100 percent prediction rate is made possible by looking at a variety of genetic and biological markers, including autoantibodies in the blood. Those at risk could now be put on a course of treatment to ward of the development of diabetes.

With diagnosed cases of Type 1 and Type 2 diabetes on the rise in the United States – and the Type 1 condition believed to affect around 1.25 million people in the US alone – such treatments could make a huge difference.

Accounting for about 5-10 percent of people with diabetes, Type 1 involves the body's own immune system attacking the pancreas, stopping the production of insulin and hampering the absorption of glucose and the production of energy.

In Type 2 diabetes, the body can't process the insulin it does make properly.

Methyldopa is far from the first drug to show benefits in treating health issues other than the ones it was first designed for, but we now have better ways to spot these extra powers: this idea of identifying certain molecules and then applying modern-day computing power to find drugs that block them could work in other situations too.

"This study has significant implications for treatment of diabetes and also other autoimmune diseases," says one of the researchers, David Ostrov from the University of Florida.

"This study suggests that the same approach may be adapted to prevent autoimmune diseases such as rheumatoid arthritis, coeliac disease, multiple sclerosis, systemic lupus erythematosus and others."

The research has been published in the Journal of Clinical Investigation.