Long-Term Safety and Efficacy of Tegoprubart in Kidney Transplant Recipients

AT-1501-K209: BESTOW-EXTENSION: A Phase 2, Multicenter, Open-Label Extension Study to Evaluate the Long-Term Safety and Efficacy of Tegoprubart in Kidney Transplant Recipients

This study will evaluate the long term safety and efficacy of AT-1501 (tegoprubart) compared with tacrolimus in patients undergoing kidney transplantation.

Study Overview

• Status: Enrolling by invitation
• Conditions: Kidney Transplant Rejection
• Intervention / Treatment: Drug: AT-1501; Drug: Tacrolimus

Detailed Description

This is a multicenter, open-label, active control extension study to assess the long-term safety and efficacy of AT-1501 (tegoprubart) compared with tacrolimus in the preservation of allograft function after kidney transplantation.

The number of patients enrolled for OLE study will depend on the enrollment in the Parent studies. To be eligible for participation in this study, participants must have completed a designated Parent study.

Participants in this study will continue the treatment regimen they were receiving in the Parent study. Dose regimens will include either AT-1501 (tegoprubart) or tacrolimus.

• Study Type: Interventional
• Enrollment (Estimated): 132
• Phase: Phase 2

Contacts and Locations

Study Locations

• Australia
  • South Australia
    • Adelaide, South Australia, Australia, 5000
      • Royal Adelaide Hospital
  • Western Australia
    • Perth, Western Australia, Australia, 6150
      • Fiona Stanley Hospital
• Brazil
  • São Paulo, Brazil, 04038-002
    • Fundação Oswaldo Ramos - Hospital do Rim
  • São Paulo, Brazil, 05403-010
    • Hospital das Clinicas da Faculdade de Medicina de Sao Paulo
• Canada
  • British Columbia
    • Vancouver, British Columbia, Canada, V6Z IY6
      • St. Paul's Hospital
  • Quebec
    • Montreal, Quebec, Canada, H4A 3J1
      • McGill University Health Care Centre
• France
  • Bordeaux, France
    • Groupe Hospitalier Pellegrin
  • Grenoble, France, 38700
    • CHU Grenoble-Alpes - Hopital Nord Michallon
  • Limoges, France, 07042
    • Centre Hospitalier Universitaire Dupuytren
  • Toulouse, France, 31400
    • CHU de Toulouse - Hôpital de Rangueil
• Germany
  • Berlin, Germany
    • Charite Universitatsmedizin Berlin
• Spain
  • Barcelona, Spain, 08035
    • Hospital Universitari Vall d'Hebron
  • Barcelona, Spain, 08907
    • Hospital Universitari de Bellvitge
  • Barcelona, Spain, 08003
    • Hospital del Mar - Parc de Salut Mar
  • Barcelona, Spain, 08916
    • Hospital Germans Trias I Pujol
  • Barcelona, Spain, 08036
    • Hospital Clinical de Barcelona
• United Kingdom
  • Oxford, United Kingdom, OX3 9DU
    • Oxford University Hospitals NHS Foundation Trust - John Radcliffe Hospital
• United States
  • California
    • Los Angeles, California, United States, 90024
      • University of California Los Angeles
    • Los Angeles, California, United States, 90033
      • Keck School of Medicine of USC
    • Orange, California, United States, 92868
      • University of California, Irvine Medical Center
    • Sacramento, California, United States, 95817
      • University of California, Davis Medical Center
    • San Diego, California, United States, 92037
      • Jacobs Medical Center at UC San Diego Health
  • District of Columbia
    • Washington D.C., District of Columbia, United States, 20007
      • MedStar Georgetown University Hospital
  • Florida
    • Tampa, Florida, United States, 33606
      • Tampa General Hospital
  • Georgia
    • Atlanta, Georgia, United States, 30322
      • Emory University Hospital
    • Augusta, Georgia, United States, 30912
      • Augusta University
  • Illinois
    • Chicago, Illinois, United States, 60637
      • University of Chicago
    • Maywood, Illinois, United States, 60153
      • Loyola University Medical Center
  • Kansas
    • Kansas City, Kansas, United States, 66160
      • University of Kansas Medical Center
  • Louisiana
    • New Orleans, Louisiana, United States, 70112
      • Tulane Medical Center
  • Maryland
    • Baltimore, Maryland, United States, 21287
      • John Hopkins University
  • Massachusetts
    • Boston, Massachusetts, United States, 02114
      • Massachusetts General Hospital
  • Michigan
    • Detroit, Michigan, United States, 48202
      • Henry Ford Health System
  • Minnesota
    • Minneapolis, Minnesota, United States, 55455
      • University of Minnesota Medical Center
    • Rochester, Minnesota, United States, 55907
      • Mayo Clinic
  • Missouri
    • St Louis, Missouri, United States, 63110
      • Washington University in St. Louis
  • Nebraska
    • Omaha, Nebraska, United States, 68198
      • University of Nebraska Medical Center
  • New York
    • New York, New York, United States, 10016
      • New York University Langone Health - Tisch Hospital
  • North Carolina
    • Durham, North Carolina, United States, 27710
      • Duke University Medical Center
  • Ohio
    • Cincinnati, Ohio, United States, 45219
      • University of Cincinnati Medical Center
  • Pennsylvania
    • Harrisburg, Pennsylvania, United States, 17104
      • University of Pittsburgh Medical Center
  • Texas
    • Dallas, Texas, United States, 75235
      • UT Southwestern
  • Virginia
    • Richmond, Virginia, United States, 23298
      • Virginia Commonwealth University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Successfully completed qualifying Parent study, where entry into the OLE was offered;
• Continue to be able to understand the key components of the study as described in the written ICF, and is willing and able to provide written informed consent;
• Agree not to participate in another interventional study while on treatment;
• If female, is surgically sterile or 2 years postmenopausal. Women of childbearing potential may be enrolled if a pregnancy test is negative at baseline. Women of childbearing potential and men with partners that are of childbearing potential must agree to use highly effective methods of contraception from baseline, through 90 days after the last administration of the study drug. Examples of acceptable methods of contraception are described in Table 6.
• If male, agree to use a medically accepted highly effective method of contraception and agree to use this method for 90 days after last administration of the study drug and agree to not donate sperm for 90 days after last administration of the study drug.

Exclusion Criteria:

• Unwilling or unlikely to comply with the study requirements, in the opinion of the Investigator;
• Met any of the stopping criteria or discontinued study drug in the Parent study;
• Pregnant or breastfeeding.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: AT-1501; AT-1501 20 mg/kg administered every 3 weeks IV + MMF 1000 mg per os (orally) (PO) twice daily (BID) or MPS 720 mg PO BID + Corticosteroids 5 mg of prednisone PO once daily (QD) or equivalent	Drug: AT-1501; AT-1501 20 mg/kg administered every 3 weeks IV + MMF 1000 mg PO twice daily (BID) or MPS 720 mg PO BID + Corticosteroids 5 mg of prednisone PO once daily (QD) or equivalent; Other Names: Tegoprubart
Active Comparator: Tacrolimus; Tacrolimus dosed PO BID with the dose titrated to maintain a trough concentration of 6-8 ng/mL+ MMF 1000 mg PO BID or MPS 720 mg PO BID + Corticosteroids 5 mg of prednisone PO QD or equivalent	Drug: Tacrolimus; Tacrolimus dosed PO BID with the dose titrated to maintain a trough concentration of 6-8 ng/mL+ MMF 1000 mg PO BID or MPS 720 mg PO BID + Corticosteroids 5 mg of prednisone PO QD or equivalent

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety and Tolerability - Incidence of Treatment Emergent Adverse Events	Incidence of treatment-emergent serious adverse events (TESAEs), treatment-emergent adverse events (TEAEs), and treatment-emergent AEs of special interest (TEAEoSI).	Assessed from date of enrollment through Month 48
Safety and Tolerability - Kidney Transplant Medication Side Effects	Kidney transplant medication side effects using the Modified Transplant Symptom Occurrence and Symptom Distress Scale-59 (MTSOSD) at baseline and 12, 24, 36, and 48 months.	Assessed from date of enrollment through Month 48

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The proportion of patient and graft survival at 12, 24, 36, and 48 months	A participant is considered to have graft functional impairment if they have an eGFR <60 mL/min/1.73m^2.	Assessed from date of enrollment through Month 48
The proportion of participants with Graft function impairment at 12, 24, 36, and 48 months	A participant is considered to have graft functional impairment if they have an eGFR <60 mL/min/1.73m^2.	Assessed from date of enrollment through Month 48
Proportion of participants with BPAR at 12, 24, 36, and 48 months	The Proportion of participants with BPAR at 12, 24, 36, and 48 months.	Assessed from date of enrollment through Month 48
Proportion of composite endpoint (graft failure, BPAR, or death) at 12, 24, 36, and 48 months	The Proportion of participants with composite endpoint (graft failure, BPAR, or death) at 12, 24, 36, and 48 months.	Assessed from date of enrollment through Month 48

Collaborators and Investigators

• Sponsor: Eledon Pharmaceuticals

Study record dates

Study Major Dates

• Study Start (Actual): October 25, 2023
• Primary Completion (Estimated): December 1, 2029
• Study Completion (Estimated): December 1, 2029

Study Registration Dates

• First Submitted: November 6, 2023
• First Submitted That Met QC Criteria: November 6, 2023
• First Posted (Actual): November 13, 2023

Study Record Updates

• Last Update Posted (Actual): December 10, 2025
• Last Update Submitted That Met QC Criteria: December 3, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Keywords: monoclonal antibody; ESRD; Prophylaxis; Kidney Transplant; AT-1501; Renal Allograft Rejection; Humanized blocking antibody to CD40L; CD40L Inhibitor; tegoprubart; renal, transplant
• Additional Relevant MeSH Terms: Urogenital Diseases; Pathologic Processes; Male Urogenital Diseases; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Chronic Disease; Disease Attributes; Renal Insufficiency; Renal Insufficiency, Chronic; Pathological Conditions, Signs and Symptoms; Kidney Failure, Chronic; Organic Chemicals; Macrolides; Lactones; Tacrolimus
• Other Study ID Numbers: AT-1501-K209; UTN (Other Identifier: U1111-1319-8000); EU CTR (Other Identifier: 2025-521908-22)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No