Edoxaban Could Safely Reduce Risk of Thromboembolism in Pediatric Patient Populations

Michael Portman, MD

Data from a phase 3 trial examining use of edoxaban in pediatric patients with cardiovascular disease at risk of thromboembolism suggests the direct oral anticoagulant (DOAC) could be a safe and effective way of alleviating disease burden among these patients.

Presented at American Heart Association’s Scientific Sessions 2022 (AHA 2022), the 168-person study, which compared edoxaban against low molecular weight heparins and/or vitamin K antagonists, indicate there were no major differences in clinically relevant bleeding events between study arms and treatment-emergent adverse events were rare among both groups.

“Our findings point to edoxaban as a new and, perhaps, better alternative to the current medications and may improve quality of life for these children,” said lead investigator Michael A. Portman, MD, director of research in the division of cardiology at Seattle Children’s Hospital and professor in the department of pediatrics at the University of Washington School of Medicine, in a statement. “A once-a-day, oral anticoagulant would be a distinct advantage for children and families, and eliminate injections and reduce the need for frequent blood tests.”

The current study was launched with the intent of examining if edoxaban was at least as safe as current standard of care in pediatric patients with cardiovascular disease considered to be at risk of thromboembolism. A phase 3, multinational, prospective, randomized, open-label, blinded-endpoint trial, ENNOBLE-ATE enrolled patients less than 18 years of age and randomized them in a 2:1 ratio to age- and weight-based oral edoxaban once-daily or standard of care for 3 months, with randomization stratified by concomitant use of aspirin and by underlying disease groups, which were defined as those with a history of Fontan procedure, Kawasaki disease, heart failure, and other cardiovascular diseases. At the conclusion of the 3-month period, both groups continued in an extension with edoxaban through 1 year.

Between May 2018-September 2021, investigators enrolled and randomized 168 children. This cohort had a mean age of 8, 65% were male, and 71% identified as White. Overall, 112 individuals were randomized to edoxaban and 56 were randomized to continue standard of care. The primary outcome of interest for the trial was adjudicated International Society on Thrombosis and Haemostasis defined clinically relevant bleeding. The trial’s secondary outcome of interest was a composite of symptomatic thromboembolism and asymptomatic intracardiac thrombosis.

Upon analysis, results indicated the rates of clinically relevant bleeding events were similar between both study arms during the 3-month portion of the trial, with investigators noting one subject in each group experiencing a nonmajor clinically relevant bleeding. When assessing for risk of treatment-emergent adverse events, results indicated such an event occurred among 46.8% (51/109) of the edoxaban group and 41.4% (24/58) of the standard-of-care group.

Among a subgroup of 152 participants who continued in the extension portion of the trial, a single clinically relevant bleeding event, which investigators pointed out was trauma related, and 4 treatment-emergent adverse events occurred during the additional 9 months of follow-up.

“If a child is having difficulty with anticoagulant treatment – for instance becoming tired of the twice-daily injections – it would be reasonable to discuss with the child’s physician or health care team about whether edoxaban is an option,” Portman added.

This study, “Edoxaban For Pediatric Patients With Cardiac Diseases: A Randomized, Open Label, Multicenter Study,” was presented at AHA 22.