SVI research points the way to lasting benefit from promising type 1 diabetes tablet

A daily tablet that protects insulin production in people newly diagnosed with type 1 diabetes is likely to work best taken continuously rather than as a short course, new SVI research shows. This finding, published recently in Diabetes Care, arrives as the drug enters the large international trials that will allow its regulatory approval as a treatment for type 1 diabetes.

The tablet, baricitinib, was first shown to protect insulin production in type 1 diabetes by SVI’s BANDIT trial, published in 2023. That work laid the groundwork for two international phase 3 trials, both run by Eli Lilly and now recruiting around the world.

The first, BARICADE-PRESERVE, is testing whether baricitinib preserves insulin production in 300 children and adults recently diagnosed with type 1 diabetes, with results expected in 2028. The second, BARICADE-DELAY, goes a step earlier: it is testing whether the tablet can delay or prevent type 1 diabetes in people known to be at high risk of developing it, following participants for up to five years.

Trials of this size are the step that has to be cleared before a treatment can be approved and made available to people living with type 1 diabetes.

SVI’s latest study answers a question that matters a great deal for those trials, and for anyone who might one day take the drug: what happens when the tablets stop?

“Knowing how long a treatment’s benefits last is important,” said Professor John Wentworth, who led the study. “That’s what tells us how the drug would actually need to be used by people living with type 1 diabetes.”

Why protecting insulin production matters

In type 1 diabetes, the immune system attacks and destroys the beta cells in the pancreas that make insulin. Protecting even a small amount of a person’s own insulin production makes blood glucose easier to manage and lowers the risk of dangerous lows and long-term complications.

In BANDIT, 91 people aged 10 to 30, all diagnosed within the previous 100 days, took either baricitinib or a placebo for 48 weeks. Those on baricitinib held on to more of their own insulin production, needed less injected insulin, and spent more time in their target blood glucose range.

The benefits faded once treatment stopped

With the results published recently in Diabetes Care, the researchers followed participants for another 48 weeks following cessation of the drug, with regular testing of how much insulin their bodies were still producing.

Six months after stopping, people who had taken baricitinib still had significantly more beta cell function than those who had taken the placebo. But by 12 months that advantage had disappeared, and the two groups looked the same. The immune changes the drug had produced reversed over the same period, and there were no lasting differences between the groups in insulin doses or blood glucose control.

Encouragingly, stopping the drug did not cause any sudden rebound or worsening of participants’ diabetes — the decline was gradual, and side effects were less frequent in the year after treatment than during it.

What it means for the trials ahead

The results suggest baricitinib is likely to work best as an ongoing treatment, taken continuously in the same way that therapies for other autoimmune conditions are, rather than as a short course given soon after diagnosis.

That is a practical and encouraging prospect: baricitinib is a tablet, is already widely used for other conditions, and was well tolerated by participants, including the youngest ones.

“We can think of this in the same way as treatments for other autoimmune conditions, where people stay on therapy to keep the disease in check,” said Professor Tom Kay, who led the BANDIT trial. “Baricitinib is a tablet that is already used safely for other diseases, which makes that a realistic prospect.”

Findings like these help ensure the larger trials now under way are designed to give the clearest possible answer about how baricitinib could help people living with type 1 diabetes — and bring the prospect of a treatment that protects insulin production closer to the clinic.

The study was funded by the Medical Research Future Fund and Breakthrough T1D.

More information on clinical trials available for people with, and at risk of, type 1 diabetes, including the BARICADE-PRESERVE trial.