Actively Recruiting
Safety Study of REGN7508 and REGN9933 Compared to Apixaban in Adults With Atrial Fibrillation (ROXI-ATLAS)
Led by Regeneron Pharmaceuticals · Updated on 2026-05-29
1200
Participants Needed
45
Research Sites
10 weeks
Total Duration
On this page
AI-Summary
What this Trial Is About
Researchers are evaluating experimental drugs called REGN7508 and REGN9933 for people with atrial fibrillation, a condition where the heart beats too fast and unevenly. The study aims to compare these new drugs with apixaban, a medicine already used to prevent blood clots in atrial fibrillation patients. The research also looks at side effects, how well the drugs reduce stroke risk, drug levels in the blood, and whether the body produces antibodies that might affect the drugs' action. Participants will be randomly assigned to receive either REGN7508, REGN9933, or apixaban according to the study plan. The drugs are given as described in the study protocol. This is a Phase 2, open-label trial with blinded endpoints, which means patients and doctors know the treatment but outcome assessments are blinded. The main treatment period lasts 12 weeks. During the study, participants will be monitored for bleeding events and other side effects up to about 25 weeks. Researchers will measure bleeding rates, stroke or embolism occurrences, drug concentrations in blood, antibody formation, and changes in blood clotting tests. Participants will have regular visits and tests to track safety and treatment effects throughout the trial.
CONDITIONS
Brief Title
Safety in Adult Participants With Atrial Fibrillation Who Are Treated With Anticoagulation
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Adults aged 18 years or older with atrial fibrillation or flutter not caused by a reversible condition
- Indication for indefinite anticoagulation treatment
- Meets specific stroke risk scores (CHA2DS2-VA score of 2 or higher) or enrichment criteria as defined in the protocol
- If taking warfarin or other Vitamin K antagonist, must have International Normalization Ratio (INR) below 2.5 at randomization
You will not qualify if you...
- Having a mechanical heart valve prosthesis (transcatheter aortic valve replacement is allowed)
- Known moderate to severe mitral stenosis
- Previous successful ablation therapy or Left Atrial Appendage occlusion/exclusion, or planned procedures as described in the protocol
- Ischemic stroke within 2 days before randomization
- Estimated glomerular filtration rate (eGFR) less than 15 mL/min/1.73m2 within 30 days prior to randomization, on dialysis, or expected to start dialysis
- History of central nervous system bleeding within 30 days before randomization
- Other protocol-defined exclusion criteria apply
AI-Screening
AI-Powered Screening
Complete this quick 3-step screening to check your eligibility
Your Study Journey
Duration - 2 to 4 weeks
Participants are screened for eligibility to participate in the trial.
1 visit (in-person)
Duration - 12 weeks
Participants receive anticoagulation treatment with REGN7508, REGN9933, or Apixaban as assigned by randomization to prevent stroke and other complications associated with atrial fibrillation.
Weekly visits for up to 12 weeks
Duration - Approximately 13 weeks
Participants are monitored for safety outcomes and treatment-emergent adverse events after the initial 12-week treatment period.
Visits every 4 weeks for approximately 13 weeks
Trial Site Locations
Total: 45 locations
1
SEC Clinical Research
Dothan, Alabama, United States, 36305
Actively Recruiting
2
Eastern Shore Research Institute
Fairhope, Alabama, United States, 36532
Actively Recruiting
3
Mission Cardiovascular Research Institute
Fremont, California, United States, 94538
Actively Recruiting
4
National Institute of California Heart and Vein Specialists
Huntington Beach, California, United States, 92648
Actively Recruiting
5
Profound Research LLC at Southern California Heart Specialists
Pasadena, California, United States, 91105
Actively Recruiting
6
Empire Clinical Research
Pomona, California, United States, 91767
Actively Recruiting
7
Northbay Clinical Research Center
Santa Rosa, California, United States, 95405
Actively Recruiting
8
Cardiology Associates Medical Group
Ventura, California, United States, 93003
Actively Recruiting
9
Interventional Cardiology Medical Group
West Hills, California, United States, 91307
Actively Recruiting
10
Nouvelle Clinical Research LLC
Cutler Bay, Florida, United States, 33189
Actively Recruiting
11
Inpatient Research Clinic LLC
Miami Lakes, Florida, United States, 33014
Actively Recruiting
12
Cardiovascular Center of Sarasota Foundation for Research and Education
Sarasota, Florida, United States, 34239
Actively Recruiting
13
Clinical Site Partners, LLC DBA Flourish Research
Winter Park, Florida, United States, 32789
Actively Recruiting
14
Health Sciences Research Building II
Atlanta, Georgia, United States, 30322
Actively Recruiting
15
NSC Research, Inc
Johns Creek, Georgia, United States, 30024
Actively Recruiting
16
Indiana University
Indianapolis, Indiana, United States, 46202
Actively Recruiting
17
Blue Coast Research Center, LLC
Indianapolis, Indiana, United States, 46237
Actively Recruiting
18
Franciscan Physician Network, Indiana Heart Physicians
Indianapolis, Indiana, United States, 46237
Actively Recruiting
19
Indiana Medical Research
Merrillville, Indiana, United States, 46410
Actively Recruiting
20
Reid Physician Associates
Richmond, Indiana, United States, 47374
Actively Recruiting
21
Monroe Research, LLC
West Monroe, Louisiana, United States, 71291
Actively Recruiting
22
Anderson Medical Research
Ft. Washington, Maryland, United States, 20744
Actively Recruiting
23
Beth Israel Lahey Health, Beth Israel Deaconess Medical Center (BIDMC)
Boston, Massachusetts, United States, 02215
Actively Recruiting
24
Profound Research, Millennium Cardiology
Farmington Hills, Michigan, United States, 48334
Actively Recruiting
25
AA Medical Research Center (MRC)
Flint, Michigan, United States, 48504
Actively Recruiting
26
Moses Cone Hospital Operating Corporation dba Cone Health, Lebauer-Brodie Center for Cardiovascular Research
Greensboro, North Carolina, United States, 27401
Actively Recruiting
27
K&R Research LLC
Marion, Ohio, United States, 43302
Actively Recruiting
28
Advanced Medical Research
Maumee, Ohio, United States, 43537
Actively Recruiting
29
Monument Health Clinical Research
Rapid City, South Dakota, United States, 57701
Actively Recruiting
30
East Coast Institute for Research, Jefferson City
Jefferson City, Tennessee, United States, 37760
Actively Recruiting
31
PharmaTex Research
Amarillo, Texas, United States, 79106
Actively Recruiting
32
Complete Heart Care P.A.
McKinney, Texas, United States, 75071
Actively Recruiting
33
Permian Research Foundation
Odessa, Texas, United States, 79761
Actively Recruiting
34
Tyler Cardiovascular Consultants
Tyler, Texas, United States, 75701
Actively Recruiting
35
Alpine Research TC
Clinton, Utah, United States, 84015
Actively Recruiting
36
University of Alberta Hospital - Cardiology
Edmonton, Alberta, Canada, T6G 2G3
Actively Recruiting
37
GA Research Associates Ltd.
Moncton, New Brunswick, Canada, E1G-1A7
Actively Recruiting
38
Health sciences North - Cardiology
Greater Sudbury, Ontario, Canada, P3E 5J1
Actively Recruiting
39
Dr James Cha
Oshawa, Ontario, Canada, L1J 2K1
Actively Recruiting
40
Heart Health Institute Research Inc. - Cardiology
Scarborough Village, Ontario, Canada, M1B 4Z8
Actively Recruiting
41
Viacar Recherches Cliniques Inc. - Cardiologie
Longueuil, Quebec, Canada, J4H 4B9
Actively Recruiting
42
Centre Hospitalier Universitaire De Sherbrooke (CHUS) - Cardiologie
Sherbrooke, Quebec, Canada, J1H 5N4
Actively Recruiting
43
Diex Recherche Inc.
Sherbrooke, Quebec, Canada, J1LOK3
Actively Recruiting
44
Diex Recherche Trois-rivieres
Trois-Rivières, Quebec, Canada, G9A 4P3
Actively Recruiting
45
CHU de Quebec-Universite Laval
Québec, Canada, G1R 2J6
Actively Recruiting
Research Team
C
Clinical Trials Administrator
How is the study designed?
Study Type
INTERVENTIONAL
Masking
SINGLE
Allocation
RANDOMIZED
Model
PARALLEL
Primary Purpose
PREVENTION
Number of Arms
3
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