Early Results Show Promise for New Immunosuppressant in Islet Transplants for Type 1 Diabetes

Islet transplantation—moving insulin-producing cells from a donor pancreas into a person with Type 1 diabetes—offers a potential path to insulin independence. However, the immune system typically attacks these foreign cells, causing rejection. Doctors currently prevent rejection using immunosuppressive drugs, including tacrolimus, a calcineurin inhibitor that can have significant side effects.

Researchers at University of Chicago Medicine are testing whether tegoprubart, an experimental antibody made by Eledon Pharmaceuticals, could protect transplanted islets without relying on tacrolimus. Tegoprubart targets CD40 Ligand, a molecule involved in immune rejection. The theory is that blocking this specific pathway might prevent rejection while reducing overall immune suppression.

In November 2025, researchers presented preliminary data from the first six patients enrolled in this investigator-initiated trial. All six patients who received islet transplants with tegoprubart-based immunosuppression achieved insulin independence—meaning their transplanted islets produced enough insulin to maintain healthy blood sugar levels without insulin injections or pumps.

The patients also demonstrated marked improvements in glycemic control, with sustained management of hemoglobin A1C (HbA1c), a measure of average blood sugar over time. The trial has been extended to include 12 total subjects, allowing researchers to gather more data on safety and effectiveness.

If tegoprubart proves effective, it could offer islet transplant patients a less toxic immunosuppression strategy. Tacrolimus and other current immunosuppressive drugs can cause kidney damage, high blood pressure, infections, and other serious side effects. A more targeted approach might reduce these risks.

However, it is important to note that this is very early data from a small group of patients in an ongoing trial. Researchers will need to follow these patients long-term to understand how durable insulin independence is, whether rejection eventually occurs, and what side effects emerge with extended use. Results from the expanded 12-patient cohort will provide a clearer picture of tegoprubart's potential.

Islet transplantation is not yet widely available or considered a first-line treatment for Type 1 diabetes. Current barriers include the scarcity of donor organs, the need for lifelong immunosuppression, and risks of rejection. Improving immunosuppressive regimens—like the approach being tested with tegoprubart—could make transplantation more feasible and safer for more patients.

This trial represents one piece of ongoing research to advance transplant outcomes. As results accumulate, they will help clinicians and patients understand whether tegoprubart-based immunosuppression offers a meaningful advantage over current approaches.

Origin: finance.yahoo.com (News report). Evidence: News report — unverified, pending corroboration. 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.