Eledon Pharmaceuticals, Inc. ("Eledon") (NASDAQ:ELDN) today announced updated results from an investigator-initiated trial conducted at the University of Chicago Medicine Transplant Institute and presented by Piotr Witkowski, M.D., Ph.D., Director of the Pancreas and Islet Transplant Program at UChicago Medicine, at the Advanced Technologies and Treatments for Diabetes (ATTD) conference, held March 11-14, 2026 in Barcelona, Spain.

The investigator-initiated pilot study enrolled 12 adults with long-standing type 1 diabetes undergoing allogeneic islet transplantation at UChicago Medicine. Patients had a median duration of diabetes of approximately 33 years and mean hemoglobin A1C ("HbA1C") of approximately 8.0% prior to transplantation. Participants received tegoprubart, Eledon's anti-CD40L monoclonal antibody, as part of a calcineurin inhibitor-free immunosuppression regimen.

The data demonstrated rapid improvement in glycemic control following islet transplantation, with stable islet graft function observed across the cohort. All 10 patients who were more than four weeks post-transplant achieved both insulin independence and a most recent HbA1c below 6.0%, with a mean most recent HbA1c across the 10 patients of approximately 5.35%. 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, which are commonly associated with tacrolimus-based immunosuppression regimens, was observed. These findings further support the potential of CD40L blockade to enable effective islet graft protection while avoiding the toxicities of calcineurin inhibitors.

"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," said David-Alexandre C. Gros, M.D., Chief Executive Officer of Eledon. "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."

"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, Ph.D., 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."

This UChicago Medicine-initiated clinical trial is funded by Breakthrough T1D, with initial support from The Cure Alliance. Breakthrough T1D has also committed 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.