A drug commonly used to treat rheumatoid arthritis can suppress the progression of type 1 diabetes in recently diagnosed patients, scientists have said.

In a world-first clinical trial, researchers in Australia have found that baricitinib, which is available in the UK under the brand name Olumiant, can preserve the body’s own insulin production, reducing the amount of insulin needed to treat the condition.

Describing the finding as “a huge step-change” in how the condition is managed and treated, the researchers said their work, published in the New England Journal of Medicine, “shows promise as a fundamental improvement in the ability to control type 1 diabetes”.

Professor Helen Thomas, from St Vincent’s Institute of Medical Research in Melbourne, who is preclinical lead on the trial, said: “We are very optimistic that this treatment will become clinically available.”

Type 1 diabetes is an autoimmune disease in which the body’s immune system mistakenly attacks and kills the cells in the pancreas that produce insulin.

People with type 1 diabetes are dependent on insulin that is administered externally in order to survive.

It is estimated that around 8.4 million people around the world had type 1 diabetes in 2021, with numbers projected to rise to 17.4 million by 2040.

In the UK, around 8% of people with diabetes have type 1 diabetes.

The researchers said there is “a substantial number” of insulin-producing cells still present in the body when type 1 diabetes is first diagnosed.

Professor Thomas Kay, of St Vincent’s Institute of Medical Research, who led the trial, said: “We wanted to see whether we could protect further destruction of these cells by the immune system.”

For the trial, funded by JDRF – a non-profit organisation focusing on type 1 diabetes research – the scientists recruited 91 people, aged between 10 and 30 years old, to take part.

As it was a double-blind randomised trial, neither the researchers nor the volunteers knew who was taking baricitinib (60 people) and who was receiving a placebo (31 people).

All patients taking part had been diagnosed with type 1 diabetes within the last 100 days and continued with their prescribed insulin therapy throughout the duration of the study.

People with type 1 diabetes in the trial who were given the drug required significantly less insulin for treatment

The researchers monitored their total daily dose of insulin, the amount of insulin produced in the body as well as their blood sugar levels.

The results showed that those in the baricitinib group were able safely and effectively to preserve their body’s own insulin production and suppress the progression of type 1 diabetes.

It is thought the drug works by dampening down the immune response mounted against insulin-producing cells in people with type 1 diabetes.

While insulin can save lives, the researchers said the therapy itself is potentially dangerous if too much or too little is administered.

Professor Kay said: “It is tremendously exciting for us to be the first group anywhere in the world to test the efficacy of baricitinib as a potential type 1 diabetes treatment.

“Up until now, people with type 1 diabetes have been reliant on insulin delivered via injection or infusion pump.

“Our trial showed that, if started early enough after diagnosis, and while the participants remained on the medication, their production of insulin was maintained.

“People with type 1 diabetes in the trial who were given the drug required significantly less insulin for treatment.”

Commenting on the research Dr Faye Riley, research communications manager at Diabetes UK, said: “It’s incredibly exciting to see more positive results from clinical trials of immunotherapies to stop type 1 diabetes in its tracks.

“For more than 100 years, people living with type 1 diabetes have relied solely on insulin, but these findings show by tackling the root of type 1 diabetes – an immune system attack – an existing drug can help to shield the pancreas, in people recently diagnosed with type 1, so they can continue making more insulin for longer.

“This can give people with type 1 diabetes much steadier blood sugar levels and help to protect against serious diabetes complications down the line.

“Immunotherapies are edging us towards a new era in type 1 diabetes treatment, and could help us overcome a major hurdle en route to finding a cure for the condition.

“This trial takes us another step closer.”