> Trialight public data. Index of pages: https://trialight.com/llms.txt > Web page: https://trialight.com/data/trial/stroke-and-systemic-embolism-prevention-in-adult-53078697-4392-437b-8ca6-a2e640d08007 > Record changed: 2026-10-13 # Stroke and Systemic Embolism Prevention in Adult Participants With Atrial Fibrillation NCT07626411 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) Phase Phase 3 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) Recruitment status Recruiting Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) Participants 15,364 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) Lead sponsor Regeneron Pharmaceuticals Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) Start date 2026-08-10 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) Number of sites 8 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) ## Title and summary **Summary** This study is researching an experimental drug called REGN7508 (called "study drug") and how it compares against another treatment called apixaban. The study is focused on people who have atrial fibrillation, which means that the heart beats too fast and unevenly. The aim of the study is to see how safe and effective REGN7508 is in preventing stroke and/or systemic embolism in participants with atrial fibrillation and how it compares against participants that will receive apixaban in this study. The study is looking at several other research questions, including: \* What side effects may happen from taking the study drug \* 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/NCT07626411) **Acronym** ROXI-EVEREST Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Short title** Stroke and Systemic Embolism Prevention in Adult Participants With Atrial Fibrillation Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Official title** A Phase 3, Randomized, Multicenter, Double-blind Study to Assess Stroke and Systemic Embolism Prevention With REGN7508, a Monoclonal Antibody Against Factor XI, Versus Apixaban in Participants With Atrial Fibrillation (ROXI-EVEREST) Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) ## Status and phase **Control arm** Active comparator Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Registry reports results** No Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Listing at source** Listed Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Recruitment status** Recruiting Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Phase** Phase 3 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Study type** Interventional Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) ## Dates **Completion date** 2029-12-10 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **First posted** 2026-06-04 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Registry last updated** 2026-08-25 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Primary completion date** 2029-09-11 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Start date** 2026-08-10 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) ## Size and sites **Participants** 15,364 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Participant count basis** Estimated Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Planned participants** 15,364 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Protocol amendments** 0 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Number of sites** 8 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) ## Sponsor and oversight **Data monitoring committee** Yes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Registry sponsor category** Industry Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Lead sponsor** Regeneron Pharmaceuticals Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Source registry** ClinicalTrials.gov Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) ## Identifiers **Registry ID** NCT07626411 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **ClinicalTrials.gov ID** NCT07626411 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) **Registry record** Open registry record Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) ## Study design **Allocation** Randomised **Model** Parallel groups **Purpose** Prevention **Masking** Quadruple masking **Masked roles** Participants, Care providers, Investigators, Outcome assessors Sources for study design Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) ## Outcomes ### Primary outcomes 1. Time to first occurrence of stroke (ischemic, hemorrhagic, or of unspecified type) or systemic embolism Timeframe: Approximately 36 months 2. Time to first occurrence of International Society on Thrombosis and Haemostasis (ISTH) major bleeding or ISTH Clinically Relevant Non-Major (CRNM) bleeding Timeframe: Approximately 36 months ### Secondary outcomes 1. Time to first occurrence of stroke (ischemic, hemorrhagic, or of unspecified type), systemic embolism, ISTH major bleeding, or ISTH CRNM bleeding Timeframe: Approximately 36 months 2. Time to first occurrence of stroke (ischemic, hemorrhagic, or of unspecified type), systemic embolism, or ISTH major bleeding Timeframe: Approximately 36 months 3. Time to first occurrence of stroke (ischemic, hemorrhagic, or of unspecified type), systemic embolism, ISTH major bleeding, or all-cause death Timeframe: Approximately 36 months 4. Time to first occurrence of ISTH major bleeding Timeframe: Approximately 36 months 5. Time to first occurrence of hemorrhagic stroke, intracerebral hemorrhage, or hemorrhagic transformation of an ischemic stroke Timeframe: Approximately 36 months 6. Time to occurrence of fatal bleeding Timeframe: Approximately 36 months 7. Number of ISTH major bleeding events Timeframe: Approximately 36 months 8. Number of ISTH CRNM bleeding events Timeframe: Approximately 36 months 9. Number of minor bleeding events Timeframe: Approximately 36 months 10. Time to all-cause death Timeframe: Approximately 36 months 11. Occurrence of Treatment-Emergent Adverse Events (TEAEs) Timeframe: Approximately 39 months 12. Severity of TEAEs Timeframe: Approximately 39 months 13. Occurrence of Anti-Drug Antibodies (ADA) to REGN7508 Timeframe: Approximately 36 months 14. Magnitude of ADA to REGN7508 Timeframe: Approximately 36 months Sources for outcomes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) ## Eligibility **Sex** All **Age groups** Adults, Older adults **Minimum age** 18 Years **Healthy volunteers** No Key Inclusion Criteria: 1. Has AF or flutter (paroxysmal or persistent), not considered to be secondary to a reversible cause, and an indication for indefinite anticoagulation treatment as described in the protocol 2. Meets one of the following: 1. CHA2DS2-VA \[C: Congestive heart failure; H: Hypertension; A2: Age ≥75 years (double points); D: Diabetes mellitus; S2: Stroke or TIA or Systemic embolism (double points); V: Vascular disease; A: Age 65-74 years\] score ≥2 and Oral Anticoagulant (OAC) naïve OR 2. CHA2DS2-VA score ≥3 OR 3. CHA2DS2-VA score of 2 AND at least 1 enrichment criteria as described in the protocol 3. Must have an International Normalized Ratio (INR) <2.5 at the time of randomization if taking warfarin or another Vitamin K Antagonist (VKA) Key Exclusion Criteria: 1. Has a mechanical heart valve prosthesis (Note: transcatheter aortic valve replacement is not an exclusion) 2. Has known moderate-to-severe mitral stenosis 3. Has had a successful ablation therapy without documented recurrent AF or a participant after Left Atrial Appendage (LAA) occlusion/exclusion or plan for ablation or LAA occlusion/exclusion within the next 6 months starting from randomization 4. Had an ischemic stroke within 2 days prior to randomization 5. Has persistent, uncontrolled hypertension (per investigator's discretion) 6. Has estimated Glomerular Filtration Rate (eGFR) <15 mL/min/1.73m2 within 30 days prior to randomization or is on dialysis or expected to be started on dialysis within the next 6 months starting from randomization Note: Other protocol-defined Inclusion/ Exclusion criteria apply Sources for eligibility Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) ## Sites - SEC Clinical ResearchDothan, United StatesRecruiting - Radin Cardiovascular Medical GroupNewport Beach, United StatesRecruiting - Southern California Heart SpecialistsPasadena, United StatesRecruiting - Sec Clinical ResearchPensacola, United StatesRecruiting - Monroe Research, LLCWest Monroe, United StatesRecruiting - PharmaTex ResearchAmarillo, United StatesRecruiting - West Houston Area Clinical Trial Consultants, LLCHouston, United StatesRecruiting - Permian Research FoundationOdessa, United StatesRecruiting Sources for sites Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) ## References ### Other registry identifiers (2) - 2025 - 2025-521617-97-00 Sources for references Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07626411) ## Related records ### Drugs (2) - [Apixaban](https://trialight.com/data/asset/apixaban-9e91f03a-6eac-4da8-9f08-88d740399be5.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 (4) - [Atrial fibrillation](https://trialight.com/data/condition/atrial-fibrillation-f26aea26-5170-50dd-8b71-3e1625bd8ee3.md) Primary condition - [Stroke disorder](https://trialight.com/data/condition/stroke-disorder-f6ef16d6-34dc-5c87-b764-37f0b5b8d504.md) - [Thrombotic disease](https://trialight.com/data/condition/thrombotic-disease-3f54ef10-d2ed-524f-a020-8ecb2eb62a52.md) - [Ulcer disease](https://trialight.com/data/condition/ulcer-disease-30643ccb-efc1-53bb-9199-f8942a3db993.md) ### Targets (3) - [F10](https://trialight.com/data/target/f10-170c83e1-bc3d-524d-b28c-6b5a17d00cb8.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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