Edoxaban for Thromboembolism Prevention in Pediatric Patients With Cardiac Disease

Background: Standard of care (SOC) anticoagulation for thromboembolism (TE) prevention in children with cardiac disease includes low molecular weight heparins or vitamin K antagonists. Limited data exists for alternate use of direct oral anticoagulants in children. Objectives: The investigators aimed to obtain safety and efficacy data for edoxaban in children. Methods: We performed a phase 3, multinational, prospective, randomized, open-label, blinded-endpoint trial in patients <18 years of age with cardiac disease (ENNOBLE-ATE [Edoxaban for Prevention of Blood Vessels Being Blocked by Clots (Thrombotic Events) in Children at Risk Because of Cardiac Disease] trial). Patients were randomized 2:1 to age- and weight-based oral edoxaban once daily vs SOC for 3 months (main study period), stratified by cardiac diagnosis. Both groups could continue in an open-label edoxaban extension arm through 1 year. The primary endpoint was adjudicated clinically relevant bleeding (CRB). The main secondary endpoint was symptomatic TE or asymptomatic intracardiac thrombosis. Results: The modified intention-to-treat cohort included 167 children. One patient per group experienced a nonmajor CRB in the main period. Treatment-emergent adverse events occurred in 46.8% (51 of 109) with edoxaban and 41.4% (24 of 58) with SOC. One SOC patient experienced 2 TE events (DVT with PE). Among 147 children in the extension, 1 CRB event (0.7%) and 4 TEs occurred (2.8%; 2 strokes and 2 of 33 Kawasaki disease patients with coronary artery thromboses and/or myocardial infarctions). Conclusions: Edoxaban is a potential alternative mode of thromboprophylaxis in children with cardiac disease showing low rates of CRB and TEs with advantages of once daily dosing and infrequent monitoring requirement. (ENNOBLE-ATE [Edoxaban for Prevention of Blood Vessels Being Blocked by Clots] (Thrombotic Events) in Children at Risk Because of Cardiac Disease trial; NCT03395639).