Key Highlights

  • Tegoprubart maintained statistically higher kidney function than tacrolimus through 24 months of follow-up.
  • Mean eGFR came in at 71 for tegoprubart versus 58 mL/min/1.73 m² for tacrolimus.
  • No transplant rejections occurred beyond six months on tegoprubart, versus seven cases on tacrolimus.
  • The FDA has granted Fast Track Designation to the program.
  • Phase 3 LEGACY trial is planned to begin in the fourth quarter of 2026.

Article

Eledon Pharmaceuticals (NASDAQ: ELDN) has posted extension data from its Phase 2 BESTOW study that strengthens the case for tegoprubart as a genuine alternative to tacrolimus, the decades-old standard-of-care immunosuppressant used in kidney transplant patients. Through 24 months of follow-up, tegoprubart maintained statistically higher kidney function than tacrolimus, a meaningful result given that preserving kidney function is the entire point of anti-rejection therapy in transplant medicine.

The numbers behind that headline are notable. Patients on tegoprubart posted a mean estimated glomerular filtration rate, or eGFR, of 71 mL/min/1.73 m², compared to 58 for those on tacrolimus. eGFR is the standard clinical measure of how well the kidneys are filtering blood, and a gap of that size at two years out suggests tegoprubart may be doing meaningfully less Collateral damage to the transplanted organ than the current standard treatment, which is well known among transplant physicians for its own kidney-toxicity concerns.

Rejection outcomes told a similar story. Beyond the six-month mark, patients on tegoprubart experienced no organ rejections at all, compared to seven rejection events among those on tacrolimus. For a transplant patient, avoiding rejection while also preserving long-term kidney function is precisely the balance that current therapies struggle to strike — tacrolimus is effective at preventing rejection but carries a well-documented cost to kidney health over time. Data suggesting a drug can do both jobs better is the kind of result that gets transplant nephrologists' attention.

The regulatory backdrop adds to the momentum. Tegoprubart already carries FDA Fast Track designation, a status intended to speed the development and review of drugs that address unmet medical needs. That designation, paired with the 24-month efficacy and safety data, sets up the company's next major step: initiating its Phase 3 LEGACY trial, targeted for the fourth quarter of 2026.

For a mid-stage biotech, extension data like this serves two purposes at once. It de-risks the program heading into a pivotal trial by demonstrating durability of effect well beyond the initial study window, and it gives the company a stronger data package to bring to potential partners or investors ahead of the more capital-intensive Phase 3 stage.

The next milestones for Eledon watchers will be the formal initiation of LEGACY later this year and any additional detail on trial design, enrollment targets, and expected timelines for that pivotal Phase 3 program.