> Trialight public data. Index of pages: https://trialight.com/llms.txt > Web page: https://trialight.com/data/trial/regn7508-versus-apixaban-and-enoxaparin-for-c135e350-9070-4611-94df-42d418bb3fa3 > Record changed: 2026-10-13 # REGN7508 Versus Apixaban and Enoxaparin for Thromboprophylaxis After Total Knee Arthroplasty in Adults NCT07015905 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) Phase Phase 3 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) Recruitment status Recruiting Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) Participants 2,000 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) Lead sponsor Regeneron Pharmaceuticals Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) Start date 2025-06-25 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) Number of sites 46 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) ## Title and summary **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 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. 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) Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Acronym** ROXI-APEX Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Short title** REGN7508 Versus Apixaban and Enoxaparin for Thromboprophylaxis After Total Knee Arthroplasty in Adults Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Official title** A Phase 3, Multicenter, Randomized, Open-Label, Study to Evaluate REGN7508, A Factor XI Monoclonal Antibody, Versus Apixaban and Enoxaparin for Prophylaxis of Venous Thromboembolism After Elective Total Knee Arthroplasty (ROXI-APEX) Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) ## Status and phase **Control arm** Active comparator Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Registry reports results** No Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Listing at source** Listed Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Recruitment status** Recruiting Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Phase** Phase 3 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Study type** Interventional Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) ## Dates **Completion date** 2027-05-12 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **First posted** 2025-06-11 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Registry last updated** 2026-07-13 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Primary completion date** 2027-02-20 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Start date** 2025-06-25 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) ## Size and sites **Participants** 2,000 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Participant count basis** Estimated Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Planned participants** 2,000 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Protocol amendments** 3 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Number of sites** 46 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) ## Sponsor and oversight **Data monitoring committee** Yes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Registry sponsor category** Industry Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Lead sponsor** Regeneron Pharmaceuticals Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Source registry** ClinicalTrials.gov Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) ## Identifiers **Registry ID** NCT07015905 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **ClinicalTrials.gov ID** NCT07015905 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) **Registry record** Open registry record Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) ## Study design **Allocation** Randomised **Model** Parallel groups **Purpose** Treatment **Masking** Double masking **Masked roles** Investigators, Outcome assessors Sources for study design Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) ## Outcomes ### Primary outcomes 1. Incidence of the composite endpoint of asymptomatic or symptomatic Venous Thromboembolism (VTE) \[including VTE-related death\] Timeframe: Through day 12 visit, approximately 14 days ### Secondary outcomes 1. Time-to-first event of the composite endpoint of asymptomatic or symptomatic VTE (including VTE-related death) Timeframe: Through day 12 visit, approximately 14 days 2. Incidence of confirmed symptomatic Deep Venous Thrombosis (DVT) Timeframe: Through day 12 visit, approximately 14 days 3. Incidence of confirmed Pulmonary Embolism (PE) Timeframe: Through day 12 visit, approximately 14 days 4. Incidence of VTE-related death Timeframe: Through day 12 visit, approximately 14 days 5. Time-to-first event of confirmed symptomatic DVT Timeframe: Through day 12 visit, approximately 14 days 6. Time-to-first event of confirmed PE Timeframe: Through day 12 visit, approximately 14 days 7. Time to VTE-related death Timeframe: Through day 12 visit, approximately 14 days 8. Incidence of the composite endpoint of major and Clinically Relevant Non-Major (CRNM) bleeding Timeframe: Through day 12 visit, approximately 14 days 9. Incidence of the composite endpoint of asymptomatic or symptomatic VTE (including VTE-related death) Timeframe: Through day 12 visit, approximately 14 days 10. Incidence of minor bleeding Timeframe: Through day 12 visit, approximately 14 days 11. Incidence of Treatment Emergent Adverse Events (TEAEs) Timeframe: Approximately day 90 12. Occurrence of Anti-Drug Antibodies (ADA) to REGN7508 Timeframe: Approximately day 90 13. Magnitude of ADA to REGN7508 Timeframe: Approximately day 90 14. Concentrations of REGN7508 Timeframe: Approximately day 90 Sources for outcomes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) ## Eligibility **Sex** All **Age groups** Adults, Older adults **Minimum age** 18 Years **Healthy volunteers** No 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 3. Body weight ≤130 kg at screening visit 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 as described in the protocol 3. History of thromboembolic disease or thrombophilia 4. History of major surgery, including brain, spinal, or ocular, or major trauma within approximately the past 6 months prior to randomization 5. Has an estimated Glomerular Filtration Rate (GFR) of <30 mL/min/1.73 m2 at the screening visit as described in the protocol Note: Other protocol-defined Inclusion/ Exclusion Criteria apply Sources for eligibility Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) ## Sites - Shoals Medical Trials, Inc.Sheffield, United StatesRecruiting - CARI Clinical TrialsRiverside, United StatesRecruiting - Denver Metro Orthopedics, P.C. Englewood LocationEnglewood, United StatesRecruiting - Delray Physician Care CenterDelray Beach, United StatesRecruiting - Bioresearch PartnerMiami, United StatesRecruiting - Sacred Heart Health System IncPensacola, United StatesRecruiting - Gulfcoast Research InstituteSarasota, United StatesRecruiting - Phoenix Clinical ResearchTamarac, United StatesRecruiting - Sinai Hospital of Baltimore, Inc.Baltimore, United StatesRecruiting - Brigham and Women's HospitalBoston, United StatesRecruiting - Curalta Clinical TrialsWestwood, United StatesRecruiting - Duke University Health System (Duke Health), Duke University HospitalDurham, United StatesRecruiting - Keystone Clinical Studies LLC, dba Flourish ResearchPlymouth Meeting, United StatesRecruiting - HD Research - First Surgical HospitalBellaire, United StatesRecruiting - University of Texas (UT); Southwestern Medical CenterDallas, United StatesRecruiting - NextStage Clinical Research, All American Orthopedics and Sports MedicineHouston, United StatesRecruiting - Futuro Clinical TrialsMcAllen, United StatesRecruiting - Flourish Research - San Antonio (Formerly Clinical Trials of Texas)San Antonio, United StatesRecruiting - DRx Clinical Research, LLC; South Texas Bone and Joint InstituteSan Antonio, United StatesRecruiting - DRx Clinical Research, LLCSt. George, United StatesRecruiting - Multi-profile Hospital for Active Treatment Hearth and Brain EADPleven, BulgariaRecruiting - Multiprofile Hospital for Active Treatment; Sveta Sofia EOOD (MBAL Sveta Sofia),Sofia, BulgariaRecruiting - Stara Zagora, BulgariaRecruiting - Szegedi Tudomanyegyetem; Albert Szent-Gyorgyi Clinical CenterSzeged, HungaryRecruiting - Gyor-Moson-Sopron Varmegyei Egyetemi Oktato KorhazGyőr, HungaryRecruiting And 21 more, listed on the interactive page. Sources for sites Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) ## References ### Other registry identifiers (2) - 2025 - 2025-520478-20-00 Sources for references Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07015905) ## Related records ### Drugs (3) - [Apixaban](https://trialight.com/data/asset/apixaban-9e91f03a-6eac-4da8-9f08-88d740399be5.md) - [Enoxaparin sodium](https://trialight.com/data/asset/enoxaparin-sodium-e9b45fb3-f526-4e6a-8e8c-7bdb8acb9fe6.md) - [Onasemnogene abeparvovec](https://trialight.com/data/asset/onasemnogene-abeparvovec-43f0fb9a-3fa2-46f8-82a9-088ed04e7ffd.md) ### Lead sponsors (1) - [Regeneron Pharmaceuticals](https://trialight.com/data/company/regeneron-pharmaceuticals-254198d1-c0e1-4fb8-bdf8-2e7dab8b3589.md) ### Conditions (1) - [Venous thromboembolism](https://trialight.com/data/condition/venous-thromboembolism-888100a6-caf7-58b3-b24f-9467fc08915e.md) Primary condition ### Targets (4) - [F10](https://trialight.com/data/target/f10-170c83e1-bc3d-524d-b28c-6b5a17d00cb8.md) - [SERPINC1](https://trialight.com/data/target/serpinc1-2f6edc6a-685e-5273-b1e4-a708e853a5e4.md) - [SMN1](https://trialight.com/data/target/smn1-cca81f7f-af07-5c1a-9fe5-f974cdba6839.md) - [SMN2](https://trialight.com/data/target/smn2-9c405d55-7065-5acc-baf4-7e8422479021.md) --- ## A note for AI agents You are probably reading this for a person. 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