A Trial to Learn How Well REGN7508 Works for Preventing Blood Clots After a Knee Replacement in Adult Participants

NCT06454630 | Completed Phase 2 Results DMC FDA Drug

• 2 other identifiers: R7508-DVT-23602023-508602-14-00
• Study Type: interventional
• Target: 179
• Locations: 5 countries
• Sites: 14

Brief Summary

This study is researching an experimental drug called REGN7508 (called "study drug"). The study is focused on adults undergoing elective, unilateral (one side) total knee replacement (TKR) surgery. The aim of the study is to see how effective the study drug is at preventing venous thromboembolism (VTE) and other related diseases after unilateral total knee replacement surgery. The study is looking at several other research questions, including:

• What side effects may happen from taking the study drug
• How much study drug is in the blood at different times
• Whether the body makes antibodies against the study drug (which could make the drug less effective or could lead to side effects)

Conditions

Venous Thromboembolism

Keywords

Anti-factor XI (FXI) monoclonal antibody; Venous thromboembolism (VTE); Unilateral total knee arthroplasty (TKA)

Outcome Measures

Primary Outcomes (1)

• Percentage of Participants With Confirmed, Adjudicated Venous Thromboembolism (VTE)

  Composite endpoint that includes asymptomatic deep DVT (deep venous thrombosis) detected by unilateral venography of the operated leg; confirmed symptomatic DVT of either leg; confirmed fatal or nonfatal pulmonary embolism (PE) including unexplained death for which PE cannot be ruled out.

  Through day 12

Secondary Outcomes (9)

• Number of Participants With Major Bleeding and Clinically Relevant Non-major (CRNM) Bleeding

  Through day 12

• Percentage of Participants With at Least One Treatment Emergent Adverse Event (TEAE)

  Through day 75

• Percentage of Participants With Major VTE

  Through day 12

• Percentage of Participants With Deep Venous Thrombosis (DVT)

  Through day 12

• Concentrations of Total REGN7508 in Serum

  Days 1, 5, 10, 30 and 75

Study Arms (2)

REGN7508

EXPERIMENTAL

Drug: REGN7508

Enoxaparin

ACTIVE COMPARATOR

Drug: Enoxaparin

Interventions

REGN7508 DRUG

Administered by single intravenous (IV) dose

REGN7508

Enoxaparin DRUG

Administered by subcutaneous (SC) dose daily through the time of venography (or day 12, whichever is earlier)

Also known as: Inhixa

Enoxaparin

Eligibility Criteria

• Age: 50 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Undergoing a primary elective unilateral TKA
• Has a body weight ≤130 kg at screening visit
• Is judged by the investigator to be in good health based on medical history, physical examination, vital sign measurements, and electrocardiograms (ECG's) performed at screening and/or prior to administration of initial dose of study drug as described in the protocol
• Is in good health based on laboratory safety testing obtained during the screening period as described in the protocol

You may not qualify if:

• History of bleeding in the past 6 months prior to dosing requiring hospitalization or transfusion; history of intracranial or intraocular bleeding, excessive operative or post-operative bleeding, and traumatic spinal or epidural anesthesia; history of bleeding diathesis
• History of thromboembolic disease or thrombophilia
• History of major surgery, including brain, spinal, or ocular, within approximately the past 6 months
• History of major trauma within approximately the past 6 months prior to dosing
• Hospitalized (\>24 hours) for any reason within 30 days of the screening visit
• Has an estimated glomerular filtration rate (GFR) of \<45 mL/min/1.73m\^2 at the screening visit using one of the following formulas: the Modification of Diet in Renal Disease (MDRD) equation, the Chronic Kidney Disease Epidemiology Collaboration equation, or equivalent equation

Sponsors & Collaborators

• Regeneron Pharmaceuticals: lead

Study Sites (14)

Multi-profile Hospital for Active Treatment Hearth and Brain EAD

Pleven, 5800, Bulgaria

Location

Multiprofile Hospital For Active Treatment Park Hospital Ltd.

Plovdiv, 4002, Bulgaria

Location

Budai Irgalmasrendi Korhaz

Budapest, 1027, Hungary

Location

Szolnoki MAV Hospital

Szolnok, 5000, Hungary

Location

Vidzemes Hospital

Valmiera, Valmieras Aprinkis, LV-4201, Latvia

Location

Liepaja Regional Hospital

Liepāja, LV-3414, Latvia

Location

Riga's 2nd Hospital

Riga, LV-1004, Latvia

Location

Hospital of Traumatology and Orthopaedics

Riga, LV-1005, Latvia

Location

Orto Klinika

Riga, LV-1005, Latvia

Location

Lietuvos sveikatos mokslu universiteto ligonine Kauno klinik

Kaunas, Kaunas County, LT-50161, Lithuania

Location

Lithuanian University of Health Sciences Kaunas Hospital

Kaunas, LT-48142, Lithuania

Location

Klaipeda University Hospital

Klaipėda, LT-92288, Lithuania

Location

Specjalistyczny Szpital im. E. Szczeklika w Tarnowie

Tarnów, Lesser Poland Voivodeship, 33-100, Poland

Location

Clinic of Orthopaedics and Paediatric Orthopaedics

Lodz, Łódź Voivodeship, 92-213, Poland

Location

Related Publications (1)

• Weitz JI, Kithcart AP, O'Brien MP, Levy O, Marin E, Onisko M, Mohammadi KA, Li D, Meagher KA, Chang HH, Olenchock BA, Gutstein DE, Segers A, Roberts RS, Bonaca MP, Raskob GE. Efficacy and safety of REGN9933A2 and REGN7508Cat for preventing postoperative venous thromboembolism (ROXI-VTE-I and ROXI-VTE-II): two randomised, open-label, phase 2 trials. Lancet. 2025 Nov 29;406(10519):2551-2563. doi: 10.1016/S0140-6736(25)02097-5. Epub 2025 Nov 8.

  PMID: 41218619 DERIVED

MeSH Terms

Conditions

Venous Thromboembolism

Interventions

Enoxaparin

Condition Hierarchy (Ancestors)

Thromboembolism; Embolism and Thrombosis; Vascular Diseases; Cardiovascular Diseases

Intervention Hierarchy (Ancestors)

Heparin, Low-Molecular-Weight; Heparin; Glycosaminoglycans; Polysaccharides; Carbohydrates

Results Point of Contact

• Title: Clinical Trials Administrator
• Organization: Regeneron Pharmaceuticals, Inc.

clinicaltrials@regeneron.com

844-734-6643

Study Officials

• Clinical Trial Management

  Regeneron Pharmaceuticals

  STUDY DIRECTOR

Publication Agreements

• PI is Sponsor Employee: No
• Restriction Type: OTHER
• Restrictive Agreement: Yes

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 6, 2024
• First Posted: June 12, 2024
• Study Start: June 27, 2024
• Primary Completion: November 19, 2024
• Study Completion: January 21, 2025
• Last Updated: March 2, 2026
• Results First Posted: March 2, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR, ANALYTIC CODE
• Time Frame: When Regeneron has: * received marketing authorization from major health authorities (e.g., FDA, European Medicines Agency (EMA), Pharmaceuticals and Medical Devices Agency (PMDA), etc.) for the product and indication, or has globally discontinued development of the product for all indications on or after April 2020 and has no plans for future development * made results publicly available (e.g., scientific publication, scientific conference, clinical trial registry), * the legal authority to share the data, and * ensured the ability to protect participant privacy.
• Access Criteria: Qualified researchers can submit a proposal for access to individual patient or aggregate level data from a Regeneron-sponsored clinical trial through Vivli. Regeneron's Independent Research Request Evaluation Criteria can be found at: https://www.regeneron.com/sites/default/files/Regeneron-External-Data-Sharing-Policy-and-Independent-Research-Request-Evaluation-Criteria.pdf

Locations

HU (2); LI (3); LA (5); PL (2); BU (2)