Atrial Fibrillation (AF)
Conditions
Keywords
Blood clots, Ischemic stroke, Systemic embolism, Pulmonary embolism, Venous Thromboembolism (VTE)
Brief summary
This study is researching 2 different experimental drugs called REGN7508 and REGN9933 (called "study drugs"). The study is focused on people who have atrial fibrillation, which means that the heart beats too fast and unevenly. When this happens, blood cannot move smoothly through the heart; it can slow down or pool in one spot, which can lead to the formation of blood clots. 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 effective and safe REGN7508 and REGN9933, individually, are in preventing ischemic stroke or systemic embolism in people with atrial fibrillation who cannot or may choose to not take blood thinners. The study is looking at several other research questions, including: * What side effects may happen from taking REGN7508 or REGN9933 * How well does REGN7508 or REGN9933 lower the risk of having an ischemic stroke and/or systemic embolism compared to the placebo * How well does REGN7508 or REGN9933 lower the risk of having a major health problem affecting heart and blood circulation compared to placebo * How well does REGN7508 or REGN9933 lower the risk of death compared to placebo * How much REGN7508 or REGN9933 is in the blood at different times * Whether the body makes antibodies against REGN7508 or REGN9933 (which could make the study drugs less effective or could lead to side effects)
Interventions
Sponsors
Regeneron Pharmaceuticals
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Key Inclusion Criteria: 1. Has AF or flutter (paroxysmal or persistent), not considered to be secondary to a reversible cause 2. At moderate to high risk for stroke defined as: 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 ≥4 OR 2. CHA2DS2-VA score of 3 AND at least 1 enrichment criteria as described in the protocol 3. Shared decision making between the participant and provider determining that the bleeding risk of Oral Anticoagulant (OAC) therapy outweighs the benefits, making the participant unsuitable for OAC therapy as described in the protocol Key
Exclusion criteria
1. Has a mechanical heart valve prosthesis (Note: transcatheter aortic valve replacement is not an exclusion) 2. Had an ischemic stroke within 2 days prior to randomization 3. Has persistent, uncontrolled hypertension (per investigator's discretion) 4. Has a history of Central Nervous System (CNS) bleeding within 30 days prior to randomization 5. Has a life expectancy less than 12 months 6. Has participated in a prior Factor XI (FXI) inhibitor study Note: Other protocol-defined Inclusion/
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Time to first occurrence of ischemic stroke or systemic embolism | Up to 36 months |
| Time to first occurrence of International Society on Thrombosis and Haemostasis (ISTH) major bleeding | Up to 36 months |
Secondary
| Measure | Time frame |
|---|---|
| Time to first occurrence of Major Adverse Cardiovascular Event (MACE) | Up to 36 months |
| Time to first occurrence of MACE, pulmonary embolism, or Venous Thromboembolism (VTE) | Up to 36 months |
| Time to first occurrence of ischemic stroke | Up to 36 months |
| Time to Cardiovascular (CV) death | Up to 36 months |
| Time to all-cause death | Up to 36 months |
| Occurrence of Treatment-Emergent Adverse Events (TEAEs) | Up to 39 months |
| Severity of TEAEs | Up to 39 months |
| Concentrations of REGN7508 over time | Up to 36 months |
| Concentrations of REGN9933 over time | Up to 36 months |
| Change from baseline in activated Partial Thromboplastin Time (aPTT) over time | Up to approximately 9 weeks |
| Change from baseline in Prothrombin time (PT)/International Normalized Ratio (INR) over time | Up to approximately 9 weeks |
| Occurrence of Anti-Drug Antibody (ADA) to REGN7508 over time | Up to 36 months |
| Magnitude of ADA to REGN7508 over time | Up to 36 months |
| Occurrence of ADA to REGN9933 over time | Up to 36 months |
| Magnitude of ADA to REGN9933 over time | Up to 36 months |
Contacts
CONTACTClinical Trials Administrator
STUDY_DIRECTORClinical Trial Management
Regeneron Pharmaceuticals
Outcome results
None listed