Venous ThromboembolismPhase 2ROXI-VTE IINCT06454630
A Trial to Learn How Well REGN7508 Works for Preventing Blood Clots After a Knee Replacement in Adult Participants
A Phase 2 study testing REGN7508 and Enoxaparin in people with Venous Thromboembolism, run by Regeneron Pharmaceuticals at 14 sites in 5 countries.
Trial 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. Read more about this study
- Who is it for?
- Ages 50 years and older
- Conditions the study is for
- Venous Thromboembolism
- What is being tested?
- REGN7508 and Enoxaparin
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 179 participants
- Where
- 14 sitesin 5 countries
- Study dates
- 27 Jun 2024to 21 Jan 2025
- Phase
- Phase 2
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 50 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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
Who cannot join
- 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
- Note: Other protocol-defined Inclusion/ Exclusion Criteria apply
Trial locations and contacts
14 sites in 5 countries.
14 sites in 5 countries
Latvia5 sites
Liepaja Regional Hospital
Liepāja, LV-3414
Riga's 2nd Hospital
Riga, LV-1004
Hospital of Traumatology and Orthopaedics
Riga, LV-1005
Orto Klinika
Riga, LV-1005
Vidzemes Hospital
Valmiera, Valmieras Aprinkis, LV-4201
Lithuania3 sites
Lietuvos sveikatos mokslu universiteto ligonine Kauno klinik
Kaunas, Kaunas County, LT-50161
Lithuanian University of Health Sciences Kaunas Hospital
Kaunas, LT-48142
Klaipeda University Hospital
Klaipėda, LT-92288
Bulgaria2 sites
Multi-profile Hospital for Active Treatment Hearth and Brain EAD
Pleven, 5800
Multiprofile Hospital For Active Treatment Park Hospital Ltd.
Plovdiv, 4002
Hungary2 sites
Budai Irgalmasrendi Korhaz
Budapest, 1027
Szolnoki MAV Hospital
Szolnok, 5000
Poland2 sites
Clinic of Orthopaedics and Paediatric Orthopaedics
Lodz, Łódź Voivodeship, 92-213
Specjalistyczny Szpital im. E. Szczeklika w Tarnowie
Tarnów, Lesser Poland Voivodeship, 33-100
About this study
Official title: A Phase 2, Multicenter, Randomized, Open-Label, Active Control Study of REGN7508, a Factor XI Monoclonal Antibody, for Prevention of Venous Thromboembolism After Elective, Unilateral, Total Knee Arthroplasty (ROXI-VTE II)
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
- Being tested
- REGN7508, Enoxaparin
- Keywords
- Anti-factor XI (FXI) monoclonal antibody, Venous thromboembolism (VTE), Unilateral total knee arthroplasty (TKA)
- Medical subject headings
- Venous Thromboembolism
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
REGN7508Drug
Administered by single intravenous (IV) dose
EnoxaparinDrug
Also called Inhixa
Administered by subcutaneous (SC) dose daily through the time of venography (or day 12, whichever is earlier)
| Study group | Role | What they receive |
|---|---|---|
| REGN7508 | Experimental | Not described Receives: Drug: REGN7508 |
| Enoxaparin | Active comparator | Not described Receives: Drug: Enoxaparin |
What is being measured
The primary outcome is the main question the study is designed to answer.
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.
Measured: Through day 12
Secondary outcomes (9)
Number of Participants With Major Bleeding and Clinically Relevant Non-major (CRNM) Bleeding
International Society on Thrombosis and Hemostasis (ISTH) criteria for Major Bleeding and CRNM Bleeding as described in the protocol
Measured: Through day 12
Percentage of Participants With at Least One Treatment Emergent Adverse Event (TEAE)
A TEAE is any untoward medical occurrence in a participant administered a pharmaceutical product, which does not necessarily have a causal relationship with this treatment.
Measured: Through day 75
Percentage of Participants With Major VTE
Major VTE is a composite endpoint that includes: proximal DVT; confirmed symptomatic DVT of either leg; confirmed fatal or nonfatal PE including unexplained death for which PE cannot be ruled out.
Measured: Through day 12
Percentage of Participants With Deep Venous Thrombosis (DVT)
DVT measured by venography of the operated leg
Measured: Through day 12
Concentrations of Total REGN7508 in Serum
Measured: Days 1, 5, 10, 30 and 75
Fold Change From Baseline in Activated Partial Thromboplastin Time (aPTT)
aPTT was used to measure the anticipated anticoagulant effect of REGN7508. Fold change is based on the follow-up value/baseline value within an arm.
Measured: Days 1, 5, 10, 30, 75
Fold Change From Baseline in Prothrombin Time (PT)
PT is a measure of extrinsic and/or common pathway function. Fold change is based on the follow-up value/baseline value within an arm.
Measured: Days 1, 5, 10, 30, 75
Number of Participants With Anti-REGN7508 Antibodies by Status
Immunogenicity characterized by anti-drug antibody (ADA) status
Measured: Through end of study; approximately Day 75
Number of Participants With Treatment-Emergent or Treatment-Boosted Anti-REGN7508 Antibodies by Maximum Titer
Immunogenicity characterized per by ADA status
Measured: Through end of study; approximately Day 75
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted12 Jun 2024
- Study start27 Jun 2024
- Primary completion19 Nov 2024
- Study completion21 Jan 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Venous ThromboembolismStudies of the same condition, open and under way.
- More trials run by Regeneron PharmaceuticalsThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 179 participants (actual)
Sponsor and investigators
- Lead sponsor
- Regeneron Pharmaceuticals
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Clinical Trial Management, Study director, Regeneron Pharmaceuticals
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06454630
- Sponsor's protocol ID
- R7508-DVT-2360
- Other IDs
- 2023-508602-14-00, 2023
- Acronym
- ROXI-VTE II
- Status last verified
- May 2026
- First submitted
- 6 Jun 2024
- Last updated
- 27 May 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: All Individual Patient Data (IPD) that underlie publicly available results will be considered for sharing.
Publications
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.
PubMed 41218619