The direct oral anticoagulant rivaroxaban showed efficacy in the treatment of acute venous thromboembolism (VTE) in children in a recent phase 3 trial, as well as a similar bleeding risk compared with standard anticoagulants. The trial results were reported in Lancet Haematology.
According to the investigators, little is known about outcomes with anticoagulant therapies in children who experience VTEs.
In the international phase 3 EINSTEIN-Jr trial (ClinicalTrials.gov Identifier: NCT02234843), patients below the age of 18 years with a history of acute VTE received either rivaroxaban (335 patients), dosed according to body weight, or a standard anticoagulation therapy (165 patients). Standard anticoagulation typically consisted of heparin or a vitamin K antagonist. Primary end points involved symptomatic, recurrent VTE events and the presence of major or clinically relevant bleeding events.
Median study follow-up was 91 days (interquartile range [IQR], 87-95) for 463 patients with a 3-month planned study duration. Median follow-up occurred at 31 days (IQR, 29-35) for 37 patients younger than 2 years of age who had a planned 1-month study duration.
The rivaroxaban group showed a rate of symptomatic, recurrent VTE of 1%, while the rate with standard therapy was 3% (hazard ratio [HR], 0.40; 95% CI, 0.11-1.41). Clot resolution appeared better with rivaroxaban compared with standard anticoagulants in imaging analyses (P =.012).
From the safety population, bleeding events that were considered clinically relevant were reported in 3% of patients on rivaroxaban and 2% of patients receiving standard anticoagulation (HR, 1.58; 95% CI, 0.51-6.27). There were no major bleeding events reported for patients on rivaroxaban; on standard anticoagulants, major bleeding occurred in 2 patients.
The investigators concluded that rivaroxaban yielded similar outcomes for children as it did for adults. “We think physicians will have the option to treat children with bodyweight-adjusted oral rivaroxaban regimens, administered as tablet or suspension, without requiring regular laboratory monitoring and dose adjustments,” they wrote.
1. Male C, Lensing AWA, Palumbo JS, et al. Rivaroxaban compared with standard anticoagulants for the treatment of acute venous thromboembolism in children: a randomised, controlled, phase 3 trial [published online November 4, 2019]. Lancet Haematol. doi:10.1016/S2352-3026(19)30219-4