New Study Tests Low-Dose IL-2 to Preserve Insulin Production in Early Type 1 Diabetes

Type 1 diabetes develops when the immune system mistakenly attacks insulin-producing beta cells in the pancreas. Research has shown that people with Type 1 diabetes have fewer regulatory T cells—immune cells that normally help prevent the body from attacking itself. Scientists believe that boosting these protective cells might help slow or stop beta cell destruction.

The DIABIL-2 trial was a double-blind, placebo-controlled study, meaning neither participants nor researchers knew who received the treatment versus placebo until the study ended. This design helps ensure results are objective and not influenced by expectations.

Researchers enrolled 19 hospital centers across five European countries and recruited people aged 6 to 35 years who had been diagnosed with Type 1 diabetes within the previous three months. Participants also needed to have measurable C-peptide levels—a sign that their pancreas was still producing some insulin.

Participants received either low-dose IL-2 or placebo using two different treatment schedules. Both started with daily injections for five days, followed by maintenance doses given either once per week (regimen B) or once every two weeks (regimen A) over nearly a year. Children and adolescents received smaller doses than adults, adjusted for body size.

Early diagnosis gives researchers a critical window to intervene. When Type 1 diabetes is first identified, people still have some beta cells producing insulin—this remaining function is called residual beta cell function. Preserving this function, even partially, can help people manage their blood sugar and potentially reduce long-term complications.

C-peptide is the marker researchers use to measure how much insulin the pancreas is still making. By tracking C-peptide levels before and after treatment, scientists can determine whether low-dose IL-2 actually protects remaining pancreatic function.

This Phase 2b trial is a critical stepping stone in drug development. Phase 2 studies test whether a treatment works and is safe in a larger group than earlier trials. The results will help researchers decide whether low-dose IL-2 deserves further testing and whether one dosing schedule works better than the other.

Any new Type 1 diabetes treatment must be proven safe and effective in clinical trials before it becomes available to patients. This study is an important part of that evidence-building process, but it is not yet a proven treatment option.

Source: The lancet. Diabetes & endocrinology. Evidence type: PubMed indexed literature. Type1Cure is an information and intelligence hub, not a medical advice service. This article summarizes published research and does not provide diagnosis, treatment, or personal medical guidance. Always talk to your own care team before changing anything about your Type 1 diabetes management.