Tegoprubart Enables Insulin Independence in Type 1 Diabetes Islet Transplant Study

Eledon Pharmaceuticals has announced updated results from an investigator-initiated trial of 12 adults with long-standing type 1 diabetes undergoing allogeneic islet transplantation who received tegoprubart as part of a calcineurin inhibitor-free immunosuppression regimen.

The pilot study was conducted at the University of Chicago Medicine Transplant Institute and results were presented by Piotr Witkowski, MD, PhD, director of the Pancreas and Islet Transplant Program at UChicago Medicine, at the Advanced Technologies and Treatments for Diabetes (ATTD) conference in Barcelona, Spain.

“T1D patients have been waiting decades for a potential functional cure, and it is very encouraging to see meaningful progress in that direction through the emerging promise of tegoprubart,” David-Alexandre Gros, MD, Chief Executive Officer of Eledon, said in a statement. “These latest findings support the potential of tegoprubart to enable effective islet graft protection while avoiding the toxicities often associated with calcineurin inhibitors, and potentially enable access to islet cell transplantation for individuals living with T1D. We are proud to contribute to these important ongoing research efforts and support the work of Dr. Witkowski and the team at UChicago Medicine. We also look forward to working closely with the FDA towards our goal of receiving regulatory guidance on a path to market for tegoprubart in islet cell transplantation later this year.”

Tegoprubart is a humanized monoclonal antibody that selectively inhibits CD40 ligand, a co-stimulatory molecule in T cell activation. It is being explored in preclinical and clinical studies in kidney allograft transplantation, xenotransplantation, islet cell transplantation, liver allograft transplantation and amyotrophic lateral sclerosis. In nephrology, phase 2 BESTOW trial data suggest tegoprubart provides comparable efficacy and superior safety to tacrolimus as the core immunosuppressant in de novo kidney transplant recipients.

The latest study in adults with long-standing type 1 diabetes included patients undergoing allogeneic islet transplantation at UChicago Medicine. Participants had a median duration of diabetes of approximately 33 years, a mean hemoglobin A1C of approximately 8.0% prior to transplantation, and received tegoprubart as part of a calcineurin inhibitor-free immunosuppression regimen.

Data presented at ATTD showed rapid improvement in glycemic control following islet transplantation, with stable islet graft function observed across the cohort. All 10 patients who were > 4 weeks post-transplant achieved both insulin independence and a most recent HbA1c < 6.0%, with a mean most recent HbA1c across the 10 patients of approximately 5.35%.

Of note, tegoprubart-based immunosuppression was generally well tolerated with reported post-transplant immunosuppression-related adverse events successfully treated by lowering the mycophenolic acid dose, if necessary. There were no rejection episodes, and no patients developed de novo donor-specific HLA antibodies. Additionally, no evidence of nephrotoxicity, hypertension or neurotoxicity was observed.

The UChicago Medicine-initiated clinical trial is funded by Breakthrough T1D, with additional commitment to fund a second study evaluating tegoprubart as part of a calcineurin inhibitor-free immunosuppression drug regimen to prevent islet transplant rejection in individuals with T1D and chronic kidney disease.

"Breakthrough T1D is proud to fund the University of Chicago’s clinical trial testing tegoprubart as a novel immunosuppression alternative for use in islet cell transplants and we are very encouraged by the early data,” said Aaron Kowalski, PhD, CEO of Breakthrough T1D. “It is exciting to see islet transplant recipients in this trial who no longer need to administer insulin and who are experiencing fewer side effects than with traditional immunosuppressive regimens."

References

1. Eledon Pharmaceuticals. Eledon Announces Updated Data from Investigator-Initiated Islet Transplant Trial of Tegoprubart in Patients with Type 1 Diabetes at UChicago Medicine. March 16, 2026. Accessed March 16, 2026. https://ir.eledon.com/news-releases/news-release-details/eledon-announces-updated-data-investigator-initiated-islet

2. Gill J. Innovation in Transplant Immunosuppression With Tegoprubart, With John Gill, MD. HCPLive. November 21, 2025. Accessed March 16, 2026. https://www.hcplive.com/view/innovation-transplant-immunosuppression-tegoprubart-john-gill-md