REGN7508 + REGN9933 for Atrial Fibrillation

(ROXI-ATLAS Trial)

This trial tests two experimental drugs, REGN7508 and REGN9933, to determine their effectiveness in preventing blood clots in individuals with atrial fibrillation, a condition where the heart beats too fast and unevenly. Participants will receive either one of these new drugs or a commonly used medication, apixaban, for comparison. The study examines possible side effects, the drugs' potential to prevent strokes, and the body's reaction to them. Individuals with atrial fibrillation who require long-term blood-thinning medication might be eligible to join. As a Phase 2 trial, the research focuses on measuring the treatment's effectiveness in an initial, smaller group, offering participants a chance to contribute to significant medical advancements.

The trial information does not specify if you need to stop taking your current medications. However, if you are taking warfarin or another Vitamin K Antagonist, your Prothrombin Time/International Normalization Ratio (PT/INR) must be below 2.5 at the time of joining the study.

Research has shown that REGN7508 and REGN9933 are promising treatments for preventing blood clots in people with atrial fibrillation, an irregular and often fast heartbeat. REGN7508 effectively prevents clots while reducing the risk of bleeding, a common issue with blood thinners. Early results suggest it might even outperform some current treatments.

For REGN9933, studies indicate that it stops excessive blood clotting without interfering with other parts of the clotting process, potentially making it safer with fewer bleeding problems.

Researchers are excited about REGN7508 and REGN9933 for atrial fibrillation because they offer a novel approach compared to standard treatments like beta-blockers, calcium channel blockers, and anticoagulants. Unlike these traditional treatments, which mainly focus on controlling heart rate or rhythm and preventing blood clots, REGN7508 and REGN9933 may target specific pathways involved in the condition. This could potentially reduce side effects and improve outcomes for patients. Additionally, these new treatments might be more effective in maintaining normal heart rhythm over a longer period, offering hope for better long-term management of atrial fibrillation.

Research has shown that the drugs REGN7508 and REGN9933, studied in separate arms of this trial, may prevent blood clots without increasing bleeding risk. These drugs target coagulation factor XI (FXI), a component of blood that aids in clot formation. By blocking FXI, both REGN7508 and REGN9933 have reduced clotting events like venous thromboembolism (VTE), which can be dangerous. Specifically, REGN7508 demonstrated a 7% rate of VTE, while REGN9933 showed a 17% rate, meeting safety standards without causing major bleeding. These results suggest that these treatments could be effective for patients with atrial fibrillation, aiming to prevent strokes and related issues.¹³⁶⁷⁸