NCT07175428RecruitingPhase 2
Safety in Adult Participants With Atrial Fibrillation Who Are Treated With Anticoagulation
A Phase 2, Randomized, Multicenter, Open-label, Blinded-endpoint Study to Evaluate the Safety of REGN7508 and REGN9933, Monoclonal Antibodies Against FXI, Versus Apixaban in Participants With Atrial Fibrillation (ROXI-ATLAS)
Source: ClinicalTrials.gov · Last updated 5 Nov 2026
Brief summary (registry, in English)
This study is researching experimental drugs called REGN7508 and REGN9933. The study is focused on participants who have atrial fibrillation, which means that the heart beats too fast and unevenly. REGN7508 and REGN9933 are designed to help stop blood clots forming in patients with atrial fibrillation. The aim of the study is to see how well REGN7508 and REGN9933 work in patients that get medicine for their atrial fibrillation. The bleeding effects of REGN7508 and REGN9933 will be compared to another medicine (apixaban), which is available on the market to treat and prevent formation of blood clots. The study is looking at several other research questions, including: * What side effects may happen from taking REGN7508 or REGN9933 * How well do the study drugs reduce the risk of having a stroke * How much of REGN7508 or REGN9933 is in the blood at different times * Whether the body makes antibodies against REGN7508 or REGN9933 (which could make the drugs less effective or could lead to side effects)
- Status (registry)
- Recruiting
- Phase (registry)
- Phase 2
- Study type
- Interventional
- Enrollment
- 1200 (estimated)
- First submitted
- 9 Sept 2025
- Start date
- 20 Oct 2025
- Primary completion date
- 9 Feb 2027
- Lead sponsor
- Regeneron Pharmaceuticals
- Diseases
- Stroke, Atrial fibrillation
- NCT number
- NCT07175428
What you commit to
- Study type: Interventional · Phase 2
- Planned participants: 1200
- From 20 Oct 2025 to the primary completion date, 9 Feb 2027
- 91 sites in 4 countries
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.
Who cannot take part
Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.
Prior treatment
- Has had successful ablation therapy or Left Atrial Appendage (LAA) occlusion/exclusion, or planned ablation or LAA occlusion/exclusion as described in the protocol
- Had an ischemic stroke within 2 days prior to randomization
- Has a history of central nervous system bleeding within 30 days prior to randomization
- Note: Other protocol-defined Inclusion/ Exclusion criteria apply
Other illness
- Has a mechanical heart valve prosthesis (Note: transcatheter aortic valve replacement is not an exclusion)
Lab values
- Has estimated Glomerular Filtration Rate (eGFR) \<15 mL/min/1.73m\^2 within 30 days prior to randomization or on dialysis or expected to be started as described in the protocol
Other
- Has known moderate-to-severe mitral stenosis
Who the study is looking for
- Has AF or flutter (paroxysmal or persistent), not felt to be secondary to a reversible cause, and an indication for indefinite anticoagulation treatment as described in the protocol
- Meets one of the following:
- CHA2DS2-VA \[C: Congestive heart failure; H: Hypertension; A2: Age ≥75 years (double points); D: Diabetes mellitus; S2: Stroke or TIA or Thromboembolism (double points); V: Vascular disease; A: Age 65-74 years\] score ≥2 and Oral Anticoagulant (OAC) naïve or
- CHA2DS2-VA score ≥3 or
- CHA2DS2-VA score of 2 and at least 1 enrichment criteria as described in the protocol
- Must have an International Normalization Ratio (INR) \<2.5 at the time of randomization if taking warfarin or another Vitamin K Antagonist (VKA)
Age in the registry: 18 years to - · Sex: All · Does not accept healthy volunteers
Sites (91)
Sites in registry order. Save your city in your profile to sort them by distance.
| Site | City | Country | Site status |
|---|---|---|---|
| STAT Research Argentina Coordinator of this site? Confirm its status | Buenos Aires | Argentina | Recruiting |
| Centro de Investigacion Clinica Coordinator of this site? Confirm its status | Ciudad Autonoma de Buenos Aires | Argentina | Recruiting |
| Sanatorio Duarte Quiros Coordinator of this site? Confirm its status | Córdoba | Argentina | Recruiting |
| DIM Clínica Privada Coordinator of this site? Confirm its status | Ramos Mejía | Argentina | Recruiting |
| Fundacion Estudios Clinicos Coordinator of this site? Confirm its status | Rosario | Argentina | Recruiting |
| Sanatorio Parque Coordinator of this site? Confirm its status | Rosario | Argentina | Recruiting |
| Centro de Investigaciones Clinicas del Litoral Coordinator of this site? Confirm its status | Santa Fe | Argentina | Recruiting |
| Centro de Investigaciones Medicas Temperley (CIMeT) Coordinator of this site? Confirm its status | Temperley | Argentina | Recruiting |
| Centro de Pesquisa Clinica do Coracao Coordinator of this site? Confirm its status | Aracaju | Brazil | Recruiting |
| Nucleo de Pesquisa do Hospital Cardiologico Costantini (NUPEC) Coordinator of this site? Confirm its status | Belo Horizonte | Brazil | Recruiting |
| Cardiologia Assistencial e de Pesquisa Ltda (Cardresearch) Coordinator of this site? Confirm its status | Belo Horizonte | Brazil | Recruiting |
| Centro de Estudos Procardio Coordinator of this site? Confirm its status | Blumenau | Brazil | Recruiting |
| AngioKormann Blumenau Coordinator of this site? Confirm its status | Blumenau | Brazil | Recruiting |
| Faculdade de Medicina de Botucatu (UNESP) Coordinator of this site? Confirm its status | Botucatu | Brazil | Recruiting |
| Hospital Universitário São Francisco na Providência de Deus Coordinator of this site? Confirm its status | Bragança Paulista | Brazil | Recruiting |
| Sociedade Hospitalar Angelina Caron Coordinator of this site? Confirm its status | Campina Grande do Sul | Brazil | Recruiting |
| Instituto De Pesquisa Clinica de Campinas (Ipecc) Coordinator of this site? Confirm its status | Campinas | Brazil | Recruiting |
| Hospital da Pontificia Universidade Catolica (PUC) Campinas Coordinator of this site? Confirm its status | Campinas | Brazil | Recruiting |
| Pontificia Universidade Catolica do Paraná (PUC) Trials Coordinator of this site? Confirm its status | Curitiba | Brazil | Recruiting |
| Quanta Diagnostico por Imagem Coordinator of this site? Confirm its status | Curitiba | Brazil | Recruiting |
| Nucleo de Pesquisa Clínica SS Coordinator of this site? Confirm its status | Curitiba | Brazil | Recruiting |
| Hospital Ruy Azeredo Coordinator of this site? Confirm its status | Goiânia | Brazil | Recruiting |
| Hospital das Clinicas da Universidade Federal de Goias Coordinator of this site? Confirm its status | Goiânia | Brazil | Recruiting |
| Via Medica Research Center Coordinator of this site? Confirm its status | Goiânia | Brazil | Recruiting |
| Hospital Maternidade e Pronto Socorro Santa Lucia Coordinator of this site? Confirm its status | Poços de Caldas | Brazil | Recruiting |
| Hospital Ernesto Dornelles Coordinator of this site? Confirm its status | Porto Alegre | Brazil | Recruiting |
| CoraCentro Pesquisa Clinica Coordinator of this site? Confirm its status | Porto Alegre | Brazil | Recruiting |
| CLINICOR - Clinica Cardiologica Ltda Coordinator of this site? Confirm its status | Ribeirão Preto | Brazil | Recruiting |
| Instituto de Cardiologia de Santa Catarina Coordinator of this site? Confirm its status | São José | Brazil | Recruiting |
| Fundacao Faculdade Regional de Medicina de Sao Jose do Rio Preto, Centro Integrado de Pesquisa (CIP) Coordinator of this site? Confirm its status | São José do Rio Preto | Brazil | Recruiting |
| Instituto Dante Pazanese de Cardiologia Coordinator of this site? Confirm its status | São Paulo | Brazil | Recruiting |
| Eurolatino Medical Research Coordinator of this site? Confirm its status | Uberlândia | Brazil | Recruiting |
| University of Alberta Hospital - Cardiology Coordinator of this site? Confirm its status | Edmonton | Canada | Recruiting |
| Health sciences North - Cardiology Coordinator of this site? Confirm its status | Greater Sudbury | Canada | Recruiting |
| Hamilton Medical Research Group (HMRG) Coordinator of this site? Confirm its status | Hamilton | Canada | Recruiting |
| Hamilton Health Sciences Corporation Coordinator of this site? Confirm its status | Hamilton | Canada | Recruiting |
| Viacar Recherches Cliniques Inc. - Cardiologie Coordinator of this site? Confirm its status | Longueuil | Canada | Recruiting |
| GA Research Associates Ltd. Coordinator of this site? Confirm its status | Moncton | Canada | Recruiting |
| Montreal Heart Institute Coordinator of this site? Confirm its status | Montreal | Canada | Recruiting |
| Dr James Cha Coordinator of this site? Confirm its status | Oshawa | Canada | Recruiting |
| CHU de Quebec-Universite Laval Coordinator of this site? Confirm its status | Québec | Canada | Recruiting |
| CISSS du Bas-Saint-Laurent - Hopital regional de Rimouski - Cardiologie Coordinator of this site? Confirm its status | Rimouski | Canada | Recruiting |
| Heart Health Institute Research Inc. - Cardiology Coordinator of this site? Confirm its status | Scarborough Village | Canada | Recruiting |
| Centre Hospitalier Universitaire De Sherbrooke (CHUS) - Cardiologie Coordinator of this site? Confirm its status | Sherbrooke | Canada | Recruiting |
| Diex Recherche Inc. Coordinator of this site? Confirm its status | Sherbrooke | Canada | Recruiting |
| CISSSLAN, Hopital Pierre-Le Gardeur Coordinator of this site? Confirm its status | Terrebonne | Canada | Recruiting |
| Diex Recherche Trois-Rivieres Coordinator of this site? Confirm its status | Trois-Rivières | Canada | Recruiting |
| Victoria Cardiac Arrhythmia Trials Coordinator of this site? Confirm its status | Victoria | Canada | Recruiting |
| PharmaTex Research Coordinator of this site? Confirm its status | Amarillo | United States | Recruiting |
| Grady Health System Coordinator of this site? Confirm its status | Atlanta | United States | Recruiting |
| Health Sciences Research Building II Coordinator of this site? Confirm its status | Atlanta | United States | Withdrawn |
| Beth Israel Lahey Health-Beth Israel Deaconess Medical Center (BIDMC) Coordinator of this site? Confirm its status | Boston | United States | Recruiting |
| Alpine Research TC Coordinator of this site? Confirm its status | Clinton | United States | Recruiting |
| Valley Clinical Trials, Inc. Coordinator of this site? Confirm its status | Covina | United States | Recruiting |
| Nouvelle Clinical Research LLC Coordinator of this site? Confirm its status | Cutler Bay | United States | Recruiting |
| SEC Clinical Research Coordinator of this site? Confirm its status | Dothan | United States | Recruiting |
| North Coast Cardiology Coordinator of this site? Confirm its status | Encinitas | United States | Recruiting |
| Eastern Shore Research Institute Coordinator of this site? Confirm its status | Fairhope | United States | Recruiting |
| Profound Research, Millennium Cardiology Coordinator of this site? Confirm its status | Farmington Hills | United States | Recruiting |
| AA Medical Research Center (MRC) Coordinator of this site? Confirm its status | Flint | United States | Recruiting |
| Mission Cardiovascular Research Institute Coordinator of this site? Confirm its status | Fremont | United States | Recruiting |
| Anderson Medical Research Coordinator of this site? Confirm its status | Ft. Washington | United States | Recruiting |
| Moses Cone Hospital Operating Corporation dba Cone Health, Lebauer-Brodie Center for Cardiovascular Research Coordinator of this site? Confirm its status | Greensboro | United States | Recruiting |
| National Institute of California Heart and Vein Specialists Coordinator of this site? Confirm its status | Huntington Beach | United States | Recruiting |
| Indiana University Coordinator of this site? Confirm its status | Indianapolis | United States | Recruiting |
| Franciscan Physician Network, Indiana Heart Physicians Coordinator of this site? Confirm its status | Indianapolis | United States | Recruiting |
| Blue Coast Research Center, LLC Coordinator of this site? Confirm its status | Indianapolis | United States | Recruiting |
| East Coast Institute for Research, Jefferson City Coordinator of this site? Confirm its status | Jefferson City | United States | Recruiting |
| NSC Research, Inc Coordinator of this site? Confirm its status | Johns Creek | United States | Recruiting |
| Fairview Health Services Coordinator of this site? Confirm its status | Maplewood | United States | Recruiting |
| K&R Research LLC Coordinator of this site? Confirm its status | Marion | United States | Recruiting |
| Advanced Medical Research Coordinator of this site? Confirm its status | Maumee | United States | Recruiting |
| Texas Institute of Cardiology PA Coordinator of this site? Confirm its status | McKinney | United States | Recruiting |
| Complete Heart Care P.A. Coordinator of this site? Confirm its status | McKinney | United States | Recruiting |
| South Florida Research Organization LLC Coordinator of this site? Confirm its status | Medley | United States | Recruiting |
| Indiana Medical Research Coordinator of this site? Confirm its status | Merrillville | United States | Recruiting |
| Inpatient Research Clinic LLC Coordinator of this site? Confirm its status | Miami Lakes | United States | Recruiting |
| Synergy Group Medical, LLC Coordinator of this site? Confirm its status | Missouri City | United States | Recruiting |
| Permian Research Foundation Coordinator of this site? Confirm its status | Odessa | United States | Recruiting |
| Profound Research LLC at Southern California Heart Specialists Coordinator of this site? Confirm its status | Pasadena | United States | Recruiting |
| Empire Clinical Research Coordinator of this site? Confirm its status | Pomona | United States | Recruiting |
| Monument Health Clinical Research Coordinator of this site? Confirm its status | Rapid City | United States | Recruiting |
| The Cardiovascular Center Coordinator of this site? Confirm its status | Redding | United States | Recruiting |
| Reid Physician Associates Coordinator of this site? Confirm its status | Richmond | United States | Recruiting |
| Northbay Clinical Research Center Coordinator of this site? Confirm its status | Santa Rosa | United States | Recruiting |
| Cardiovascular Center of Sarasota Foundation for Research and Education Coordinator of this site? Confirm its status | Sarasota | United States | Recruiting |
| Tyler Cardiovascular Consultants Coordinator of this site? Confirm its status | Tyler | United States | Recruiting |
| Cardiology Associates Medical Group Coordinator of this site? Confirm its status | Ventura | United States | Recruiting |
| Interventional Cardiology Medical Group Coordinator of this site? Confirm its status | West Hills | United States | Recruiting |
| Monroe Research, LLC Coordinator of this site? Confirm its status | West Monroe | United States | Recruiting |
| Clinical Site Partners, LLC dba Flourish Research Coordinator of this site? Confirm its status | Winter Park | United States | Recruiting |
This page is information, not medical advice. Discuss any trial with your doctor.