Safety and Tolerability of Abelacimab (MAA868) vs. Rivaroxaban in Patients With Atrial Fibrillation

Inclusion Criteria: * Male and female patients ≥ 55 years old * Patients with a history of atrial fibrillation (AF) or atrial flutter with planned indefinite anticoagulation * Patients with a CHA2DS2-VASc of ≥4 OR a CHA2DS2-VASc of ≥3 with at least 1 of the following: 1. Planned concomitant use of antiplatelet medication use (i.e., aspirin and/or P2Y12 inhibitor) for the duration of the trial 2. Creatinine Clearance (CrCl) ≤50 ml/min by the Cockcroft-Gault equation Exclusion Criteria: * History of hypersensitivity to any of the study drugs (including rivaroxaban) or its excipients, to drugs of similar chemical classes, or any contraindication listed in the label for rivaroxaban * Patients with an intracranial or intraocular bleed within the 3 months prior to screening * Clinically significant mitral stenosis (valve area \<1.5 cm2) * Mechanical heart valve or other indication for anticoagulation therapy other than atrial fibrillation (e.g., venous thromboembolism) * Known presence of an atrial myxoma or left ventricular thrombus * History of left atrial appendage closure or removal * Active endocarditis Other protocol defined Inclusion/Exclusion criteria may apply