Eledon Achieves Sustained eGFR Advantage with Tegoprubart Over Tacrolimus in Phase 2 BESTOW Extension

Long-term extension data from Eledon Pharmaceuticals' Phase 2 BESTOW program signal a clinically meaningful shift in transplant immunosuppression, with tegoprubart sustaining a statistically significant kidney function advantage over tacrolimus through 18 months, a finding that will inform Phase 3 protocol design and, downstream, formulation and manufacturing strategy for CD40L-targeting biologics.

Presented at the American Transplant Congress (June 20–24, 2026, Boston), the data showed tegoprubart-treated patients maintained a mean eGFR of 74 mL/min/1.73 m² versus 61 mL/min/1.73 m² in the tacrolimus arm at month 18 (p<0.05), an approximately 12 mL/min/1.73 m² difference. eGFR stabilised after the first month of treatment and held higher at every reported time point, with mean follow-up reaching 21 months across 89 patients followed through month 18 and 20 through month 24.

The rejection profile reinforces the functional data. No biopsy-proven acute rejection (BPAR) events were observed in tegoprubart-treated patients after the first six months post-transplant. In contrast, seven of 11 total BPAR events in the tacrolimus arm, approximately 64%, occurred after the six-month mark, including one new case of active antibody-mediated rejection and one recurrent case of active T-cell-mediated rejection with antibody-mediated components beyond month 12. Patient-reported outcome measures at 52 weeks also favoured tegoprubart on two validated symptom-burden instruments.

Of the patients who completed 12 months in the core BESTOW study, 96% (49/51) of tegoprubart-treated patients and 86% (48/56) of tacrolimus-treated patients enrolled in the extension, providing a retention rate that strengthens the durability read. The longest-followed patient reached approximately 33 months as of the data cutoff.

For development and manufacturing teams, the Phase 3 transition carries practical weight. Tegoprubart is a CD40L-targeting biologic, a mechanistic class that differs substantially from small-molecule calcineurin inhibitors in its upstream process development requirements, cell line characterisation, glycosylation control, and sterility assurance under 21 CFR Part 211 and ICH Q10 quality system frameworks. CDMOs with transplant biologics experience will need to align process validation packages to the scale and comparability standards a Phase 3 IND amendment will demand.

Eledon confirmed a conference call and webcast was held June 22 at 8:00 a.m. ET to discuss the data; Phase 3 advancement timelines were not disclosed in the released materials.

The Phase 3 design, once filed, will set the comparability and process validation benchmarks that contract manufacturers and internal QA teams must meet before any commercial-scale campaign can proceed.

Source: Eledon Pharmaceuticals via GlobeNewswire, June 22, 2026. Conference call and webcast held June 22, 2026, at 8:00 a.m. ET.