Eledon drug beats tacrolimus in kidney transplant follow-up study

Eledon Pharmaceuticals said its experimental immunosuppressant tegoprubart outperformed tacrolimus in a longer follow-up of kidney transplant recipients, adding new momentum to a drug aimed at easing one of transplantation’s hardest trade-offs: preventing rejection without exposing patients to the toxic effects of lifelong therapy. The results were presented at the American Transplant Congress in Boston, where the company highlighted a roughly 12 mL/min/1.73 m² advantage in estimated glomerular filtration rate, or eGFR, at month 18.

The Phase 2 BESTOW program enrolled 127 kidney transplant recipients across 44 global sites, with 63 assigned to tegoprubart and 64 to tacrolimus. All patients also received rabbit antithymocyte globulin induction plus mycophenolate mofetil or mycophenolic acid and corticosteroids, making the comparison a head-to-head test of the two maintenance strategies on top of standard transplant care. In the long-term extension, Eledon said the tegoprubart group had no graft loss and no biopsy-proven acute rejection events after the first six months after transplant.

Tacrolimus, approved in 1994, remains the backbone of kidney transplant immunosuppression, but its broad immune suppression and kidney toxicity have long limited how far clinicians can push doses without harming long-term function. That is why Eledon’s data drew attention: better kidney function was seen from one month onward in the tegoprubart group, and the company said the drug also posted better patient-reported outcomes at 52 weeks on two validated measures of symptom burden.

The safety profile also favored tegoprubart in several categories. Eledon cited lower rates of headache, acute kidney injury, extremity pain, falls and loss of balance versus tacrolimus. In the extension data, the tacrolimus group recorded seven biopsy-proven acute rejection events, or 9.4 percent, while the tegoprubart arm had none after month 6. That is a meaningful signal, but it remains early: the study is still mid-stage, and the data have not yet been tested in a pivotal trial large enough to change practice.

Tegoprubart is a monoclonal antibody directed against CD40 ligand, a key co-stimulatory pathway in transplant immunity. The drug was engineered with an Fc design intended to avoid the thromboembolic safety problems that hindered earlier anti-CD40L antibodies, a history that has made the target intriguing but difficult to pursue.

Eledon said it is planning Phase 3 development after BESTOW. For transplant teams weighing rejection against decades of cumulative toxicity, the latest data suggest tegoprubart could eventually offer a more selective way to protect the graft while preserving kidney function and day-to-day quality of life.