Phase 2 Study Comparing Safety of REGN7508 and REGN9933 Versus Apixaban in Adults With Atrial Fibrillation

What this Trial Is About

Researchers are evaluating two experimental drugs, REGN7508 and REGN9933, in adults with atrial fibrillation, a condition where the heart beats too fast and unevenly. The study aims to compare how well these drugs prevent blood clots and their bleeding effects against apixaban, a commonly used medicine for preventing blood clots in atrial fibrillation. The research also explores side effects, drug levels in the blood, and whether the body develops antibodies that might affect the drugs action or cause side effects. Participants will be randomly assigned to receive REGN7508, REGN9933, or apixaban according to the study protocol. The treatments are given as monoclonal antibodies targeting FXI for the experimental drugs, while apixaban is an active comparator. The study is conducted with a parallel design in multiple centers, focusing on safety and prevention over a 12-week period primarily. During the study, participants will have regular monitoring to assess bleeding events, side effects, blood levels of the study drugs, and antibody responses over approximately 25 weeks. Researchers will measure various bleeding outcomes, stroke or embolism incidence, and changes in blood clotting times. Safety and treatment effects will be tracked closely throughout the trial period, which continues until study completion in 2027.

Safety in Adult Participants With Atrial Fibrillation Who Are Treated With Anticoagulation