Abstract 9192: Efficacy and Safety of Dabigatran in the Treatment and Secondary Prophylaxis of Children With Congenital Heart Disease

Abstract

Introduction: Congenital heart disease (CHD) is associated with an increased frequency of thrombotic events in children, particularly in cyanotic conditions (i.e., single ventricles). Phase IIb/III clinical trials in children with venous thromboembolism (VTE) reported the noninferiority of dabigatran etexilate (DE) versus standard of care in treating acute VTE (DIVERSITY, NCT01895777) and a favorable safety profile for VTE prevention (NCT02197416). Aim: To evaluate the efficacy and safety of DE in the treatment and secondary prophylaxis of VTE in children with CHD, including subsets with cyanotic CHD. Methods: The primary composite efficacy endpoint in DIVERSITY was complete thrombus resolution and freedom from VTE recurrence or VTE-related death; safety endpoints included bleeding events (BEs). Primary endpoints in the VTE prevention trial were VTE recurrence and BEs. CHD status was confirmed locally using standard diagnostic modalities. Results: In DIVERSITY, 48/267 (18.0%) children had CHD. DE was noninferior to standard of care in both the CHD and non-CHD groups for the composite primary endpoint ( Table ), irrespective of the presence of cyanotic or noncyanotic CHD ( Table ). BEs (mainly minor) appeared to be lower in the CHD (8.3%) than the non-CHD group (25.7%), regardless of treatment. In the secondary VTE prevention trial, 17/211 (8.1%) children had CHD. Recurrent VTE at 12 months occurred in 0 and 3 (1.5%) children in the CHD and non-CHD groups respectively ( Table ). Conclusions: In children with CHD, DE has an efficacy and safety profile consistent with the overall DIVERSITY trial. Furthermore, our results confirm the safety profile for secondary VTE prevention, suggesting that DE is a viable anticoagulant alternative for this population.