Eledon’s tegoprubart maintained higher kidney function than tacrolimus through 24 months in Phase 2 BESTOW kidney transplant data.
Written By: Kalyani Boharapi,
M.Pharm (Reg. Affairs)
Reviewed By: Pharmacally Editorial Team
Eledon Pharmaceuticals reported updated long-term Phase 2 BESTOW data (NCT06126380) showing that tegoprubart maintained higher kidney graft function than tacrolimus through 24 months after transplantation. The FDA has also granted Fast Track designation to tegoprubart for prevention of kidney transplant rejection, with a Phase 3 study planned for the fourth quarter of 2026.
Tegoprubart Shows Sustained Kidney Function Benefit
In the BESTOW long-term extension, mean estimated glomerular filtration rate (eGFR) remained statistically significantly higher with tegoprubart at months 18, 21 and 24. At month 24, mean eGFR was 71 mL/min/1.73 m² with tegoprubart versus 58 mL/min/1.73 m² with tacrolimus, an approximately 13 mL/min/1.73 m² difference. The 95% confidence interval for the treatment difference was 2.6 to 23.3 mL/min/1.73 m².
As of the August 31, 2026 data cutoff, 90 patients had been followed through 18 months and 81 patients had been followed through 24 months. The analysis therefore reflects the patients with available long-term follow-up at each time point, without implying a specific reason for the difference in patient numbers.
Rejection Outcomes Also Favor Tegoprubart
No biopsy-proven acute rejection (BPAR) events were reported in the tegoprubart arm after six months post-transplant. Seven BPAR events occurred in the tacrolimus arm during the corresponding period, while one additional case of graft loss was reported in the tacrolimus group.
These findings are relevant to long-term immunosuppression after kidney transplantation, where clinicians must balance prevention of rejection with preservation of kidney graft function. The sustained eGFR difference observed in BESTOW provides an important clinical measure for assessing tegoprubart as development progresses.
Targeting the CD40L Pathway
Tegoprubart is an investigational anti-CD40L antibody that binds CD40 Ligand (CD40L), a key costimulatory pathway involved in immune activation. Eledon is developing the therapy as a non-lymphocyte-depleting immunomodulatory approach to transplantation.
The Phase 2 BESTOW program evaluated tegoprubart in kidney transplant recipients, with patients who completed the randomized treatment period eligible to continue into a long-term extension. The extension is providing additional data on graft function, rejection and longer-term safety.
FDA Grants Fast Track Designation
Alongside the updated clinical data, the FDA granted Fast Track designation to tegoprubart for the prevention of rejection in kidney transplantation.
Fast Track designation can facilitate more frequent interactions between the FDA and a drug developer and may allow rolling submission of portions of a future marketing application. The designation does not establish efficacy or guarantee regulatory approval.
Eledon CEO David-Alexandre C. Gros said the long-term BESTOW findings and FDA designation support the company’s plan to advance tegoprubart into Phase 3 development.
Phase 3 LEGACY Trial Planned for Q4 2026
Following an End-of-Phase 2 meeting with the FDA, Eledon plans to initiate the global Phase 3 LEGACY study in the fourth quarter of 2026. The company expects to enroll approximately 600 kidney transplant recipients.
The Phase 2 BESTOW program generated the current 24-month findings, while LEGACY will provide the larger pivotal evaluation of tegoprubart versus tacrolimus.
LEGACY’s primary endpoint will assess non-inferiority of tegoprubart versus tacrolimus at 12 months using a composite efficacy-failure endpoint comprising biopsy-proven acute rejection, graft loss and death.
The Phase 3 study will therefore test whether the clinical findings observed in BESTOW, including the sustained difference in kidney function and the post-six-month rejection profile, can be reproduced in a larger controlled population.
Reference
Eledon Presents Updated Long-Term Phase 2 BESTOW Extension Study Results at the International Congress of The Transplantation Society, Eledon Pharmaceuticals, 22 September 2026
Long-Term Safety and Efficacy of Tegoprubart in Kidney Transplant Recipients, ClinicalTrials.gov ID NCT06126380
Safety and Efficacy of Tegoprubart in Patients Undergoing Kidney Transplantation, ClinicalTrials.gov ID NCT05983770
About the Writer
Kalyani Boharapi (LinkedIn) is a pharmacy professional and healthcare writer currently pursuing an M.Pharm in Regulatory Affairs at Dr. D. Y. Patil College of Pharmacy, with interests in pharmaceutical regulations, drug development, and healthcare innovation. She has academic exposure to dossier preparation, scientific writing, and regulatory documentation. Kalyani has also completed certification courses in Generative AI, AI in Pharma, and Bioinformatics, and actively participates in pharmaceutical conferences to stay updated with emerging trends and advancements in the healthcare and pharmaceutical industry.