Treatment of VTE in acutely ill children has been largely based on adult data but new paediatric research is showing rivaroxoban is effective in reducing thrombotic burden without increased bleeding.

Professor Christoph Male, from the department of paediatrics at the Medical University of Vienna, presented late-breaking findings from the EINSTEIN-Junior phase 3 trial of rivaroxaban versus standard anticoagulants.

In the trial of 500 children 0-17 years with acute VTE, patients received age and body weight-adjusted dosing, once, twice or three times daily, of a paediatric oral suspension equivalent to 20 mg rivaroxaban in adults.

Children were enrolled from 107 sites across 28 countries including Australia. Most children (45.1%) had a transient risk factor for their VTE including major infection, surgery or trauma.

Participants included children with cancer, those undergoing surgery for congenital heart disease, premmies with venous catheters and sinovenous thrombosis triggered by infection.

Professor Male said the DOACs were important for children because of the oral route of administration and because they need less monitoring.

“The only randomised controlled trial in children was many years ago. Most of what we do is based on what we know in adults,” he said.

Professor Male said the main efficacy findings were low rates of recurrent VTE (1.2% with rivaroxaban v 3.0% with a comparator, HR 0.40).

Major or clinically relevant non-major bleeding rates were 3% with the DOAC and 1.9% with heparin or a vitamin K antagonist.

Overall the net clinical benefit was 1.2% with the DOAC compared to 4.2% with the comparator, he said.

Based on repeat imaging, the thrombotic burden was normalised in 38.2% or improved (38.5%) with rivaroxaban compared to 26.1% and 45.5% with the comparator.

The clinical course of VTE in children was comparable with similar data from previous adult studies.

He said bleeding in children was less common than in adults regardless of the type of anticoagulant used.