Arthritis Drug May Offer Hope for Type 1 Diabetes

A common drug used for rheumatoid arthritis – baricitinib – has shown promising results for patients with type 1 diabetes (T1D).

A world-first trial, published in The New England Journal of Medicine, showed baricitinib could limit the progression of T1D if given during patients’ first 100 days after diagnosis.

Developing new treatment options for type 1 diabetes

T1D is a lifelong autoimmune disease in which the immune system mistakenly attacks insulin-producing cells in the pancreas, leaving patients unable to regulate their blood glucose levels.

T1D was considered a fatal condition until 100 years ago. With the discovery of insulin, however, the disease can now be managed – but it still represents a significant burden for patients and their families.

Even with meticulous management, T1D can still lead to long-term complications such as stroke, vision problems, kidney disease and nerve damage.

Bringing new drugs to market for conditions such as T1D is incredibly costly and takes many years of trials. Researchers are increasingly turning to drug repurposing – i.e., trawling through libraries of existing drugs for other conditions – to find any that might be effective.

Researchers from St. Vincent’s Institute of Medical Research tested whether baricitinib – a drug used for rheumatoid arthritis, also an autoimmune disease – could be effective for T1D.

“It is tremendously exciting for us to be the first group anywhere in the world to test the efficacy of baricitinib as a potential T1D treatment,” said Thomas Kay, senior author of the study and honorary professor of medicine at St Vincent’s Hospital.

Promising clinical trial results for baricitinib

The randomized, double-blind and placebo-controlled Phase 2 trial monitored the blood glucose and insulin production of 91 participants for 1 year. Of these participants, 60 were given baricitinib and 31 received a placebo.

Participants were aged 10–30 years old and began the trial within 100 days of their T1D diagnosis, alongside their prescribed insulin therapy.

Baracitinib treatment appeared to preserve the insulin-secretion capacity of pancreas cells, as measured by levels of C-peptide, which is released with insulin production. Variation in glucose level was also lower in the baricitinib-treated group compared to placebo, and treated patients also spent a larger percentage of time within the target range of glucose levels.

“When T1D is first diagnosed there is a substantial number of insulin-producing cells still present,” Kay said. “We wanted to see whether we could protect further destruction of these cells by the immune system. We showed that baricitinib is safe and effective at slowing the progression of T1D in people who have been recently diagnosed.”

A potential disease-modifying treatment

The study reveals baricitinib as potentially the first disease-modifying treatment of its kind for T1D that can be taken as a pill.

“Up until now, people with T1D have been reliant on insulin delivered via injection or infusion pump,” Kay continued. “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 T1D in the trial who were given the drug required significantly less insulin for treatment.” 

“We are very optimistic that this treatment will become clinically available,” said Professor Helen Thomas, preclinical lead on the trial. “This would be a huge step-change in how T1D is managed and we believe it shows promise as a fundamental improvement in the ability to control T1D.”

Reference: Waibel M, Wentworth JM, So M, et al. Baracitinib and β-cell function in patients with new-onset type 1 diabetes. NEJM. 2023. doi: 10.1056/NEJMoa2306691

This article is a rework of a press release issued by St Vincent's Institute of Medical Research. Material has been edited for length and content.