Eledon Achieves 100% Insulin Independence Rate in Tegoprubart Islet Transplant Trial Across 12 Patients

A calcineurin inhibitor-free immunosuppression protocol built around tegoprubart delivered insulin independence in all 12 patients enrolled in an investigator-initiated allogeneic islet cell transplant trial at UChicago Medicine, raising substantive questions for GMP-compliant islet cell manufacturing programs about how novel CD40L-blocking regimens may redefine post-transplant product performance benchmarks.

Updated results, presented by Piotr Witkowski, M.D., Ph.D., at the American Diabetes Association 86th Scientific Sessions on June 8, 2026, showed stable islet graft function across the cohort over a median follow-up of 8 months and a maximum of 22 months. Mean HbA1c fell to approximately 5.4% from a baseline of approximately 8.0%, a reduction of roughly 2.6 percentage points. No severe hypoglycemic episodes were recorded post-transplant, despite all 12 participants reporting recurrent severe hypoglycemic events prior to enrollment.

For cell therapy manufacturing teams, the engraftment signal carries direct process implications. Higher post-transplant islet cell engraftment was observed with the tegoprubart-based regimen compared with historical tacrolimus-treated patients at the same institution. Because tacrolimus is itself directly toxic to insulin-producing islet cells, its removal from the immunosuppression stack reduces a known variable that has historically complicated release-criteria interpretation for allogeneic islet products manufactured under 21 CFR Part 211 and current GMP frameworks. The absence of de novo donor-specific HLA antibodies and zero rejection episodes across the cohort reinforces the graft-protection profile.

Eledon Pharmaceuticals, the Irvine, California-based developer of tegoprubart, reported that immunosuppression-related adverse events were managed by dose reduction of mycophenolic acid where necessary. No nephrotoxicity, hypertension, or neurotoxicity was observed, toxicities commonly associated with calcineurin inhibitor regimens and a persistent concern in long-term islet transplant protocols. The tolerability profile, if sustained in larger controlled studies, could influence how quality and regulatory teams at cell therapy manufacturers define acceptable immunosuppression co-administration criteria in investigational new drug submissions and biologics license applications.

The pilot enrolled adults with a median diabetes duration of approximately 33 years, a population whose long-standing disease history and pre-transplant hypoglycemia burden represent a meaningful clinical baseline for interpreting graft durability data as follow-up extends beyond the current 22-month maximum.

Confirmation of these outcomes in a randomized, controlled setting will be the critical checkpoint determining whether tegoprubart-based protocols advance toward regulatory-grade process validation requirements for commercial allogeneic islet cell manufacturing.

Source: Eledon Pharmaceuticals via GlobeNewswire, June 8, 2026. Data presented at the American Diabetes Association 86th Scientific Sessions, New Orleans, Louisiana, June 5–9, 2026.