Recruiting

Phase 3

REGN7508 vs. ASAREGN7508 Versus Acetylsalicylic Acid (ASA) for Venous Thromboprophylaxis After Total Knee Arthroplasty in Adult Participants

Sponsor:

Regeneron Pharmaceuticals

Code:

NCT07213778

Conditions

Symptomatic Venous Thromboembolism (VTE)

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

REGN7508

Acetylsalicylic Acid (ASA)

Placebo

Study Details

Brief summary:

This study is researching an experimental drug called REGN7508 (called "study drug") and how it compares against another treatment called Acetylsalicylic Acid (ASA). The study is focused on adults undergoing elective, unilateral (one side) total knee replacement 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 total knee replacement surgery compared to acetylsalicylic acid.

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 study drug less effective or could lead to side effects)

Conditions

Symptomatic Venous Thromboembolism (VTE)

Study ID

NCT07213778

Start date

Nov 24, 2025

Status verified date

Aug, 2026

Completion date

Jul 16, 2027

Anticipated

Primary completion date

May 17, 2027

Anticipated

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Key Inclusion Criteria:

1. Is undergoing a primary elective unilateral TKA
2. Is in good health based on laboratory safety testing as described in the protocol

Key Exclusion Criteria:

1. Any condition that, as assessed by the investigator, may confound the results of the study or pose an additional risk to the participant by study participation
2. History of bleeding in the 6 months prior to randomization 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 (eg, hemophilia A or B, von Willebrand's Factor deficiency)
3. History of thromboembolic disease or thrombophilia
4. History of platelet dysfunction
5. Has received or plans to receive preoperative enoxaparin on the day prior to TKA surgery

Note: Other protocol-defined Inclusion/ Exclusion criteria apply

Study Design

Enrollment

2000 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: REGN7508 and Placebo

active comparator: Placebo and ASA

Interventions

REGN7508

Administered per the protocol

Acetylsalicylic Acid (ASA)

Administered per the protocol

Placebo

Administered per the protocol

Primary outcome measure

Incidence of the composite endpoint of symptomatic VTE and all-cause death [ Time Frame: Through day 30 visit ]

Central Contacts and Locations

Central contacts

Clinical Trials Administrator

844-734-6643 clinicaltrials@regeneron.com

Locations

Horizon Clinical Research

Recruiting

La Mesa, California, United States, 91942

Eisenhower Medical Center

Recruiting

Rancho Mirage, California, United States, 92270

Sky Ridge Medical Center

Recruiting

Lone Tree, Colorado, United States, 80124

South Florida Joint Replacement Center

Recruiting

Deerfield Beach, Florida, United States, 33064

Medical Research of Westchester - MPLUS Research Network

Recruiting

Miami, Florida, United States, 33165

Larkin Community Hospital South Miami

Recruiting

South Miami, Florida, United States, 33143

Phoenix Clinical Research

Recruiting

Tamarac, Florida, United States, 33321

Endeavor Health

Recruiting

Skokie, Illinois, United States, 60076

The Orthopaedic Research Foundation, Inc.

Recruiting

Indianapolis, Indiana, United States, 46278

NextStage Clinical Research, St. Francis Medical Park

Recruiting

Wichita, Kansas, United States, 67214

Velocity Clinical Research, Annapolis

Recruiting

Annapolis, Maryland, United States, 21401

Sinai Hospital of Baltimore, Inc.

Recruiting

Baltimore, Maryland, United States, 21215

Tufts Medical Center

Recruiting

Boston, Massachusetts, United States, 02111

Boston Medical Center

Recruiting

Boston, Massachusetts, United States, 02118

Holy Name Medical Center

Recruiting

Teaneck, New Jersey, United States, 07666

University of Rochester Medical Center

Recruiting

Rochester, New York, United States, 14623-5863

Eximia Equihealth Research-Raleigh. LLC

Recruiting

Raleigh, North Carolina, United States, 27612

The Vein and Vascular Center at Raleigh Radiology

Recruiting

Raleigh, North Carolina, United States, 27612

Coastal Vascular Institute, PA

Recruiting

Wilmington, North Carolina, United States, 28401

University of Cincinnati

Recruiting

Cincinnati, Ohio, United States, 45267

The Ohio State University Wexner Medical Center

Recruiting

Columbus, Ohio, United States, 43210

Ohio Clinical Trials

Recruiting

Columbus, Ohio, United States, 43212

University of Pittsburgh

Recruiting

Pittsburgh, Pennsylvania, United States, 15213-3108

HD Research - Memorial Hermann Village

Recruiting

Houston, Texas, United States, 77043

NextStage Clinical Research, All American Orthopedics and Sports Medicine

Recruiting

Houston, Texas, United States, 77058

Flourish Research - San Antonio (Formerly Clinical Trials of Texas)

Recruiting

San Antonio, Texas, United States, 78229

Carilion Clinic

Recruiting

Roanoke, Virginia, United States, 24015

Spokane Joint Replacement Center

Recruiting

Spokane, Washington, United States, 99218

More Information

Sponsor

Regeneron Pharmaceuticals

Last update posted

Aug 19, 2026

Last verified

Aug, 2026

Keywords

Total Knee Arthroplasty (TKA)
Elective Unilateral TKA
Deep Vein Thrombosis (DVT)
Pulmonary Embolism (PE)

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-08. This information was provided to ClinicalTrials.gov by Regeneron Pharmaceuticals on 2026-08-19.