Monagle P, Lensing AWA, Thelen K, et al. - In this phase 2 programme, researchers sought to develop paediatric rivaroxaban regimens for venous thromboembolism management in children and adolescents. They included children younger than 6 months, aged 6 months to 5 years, and aged 6–17 years, and assessed rivaroxaban treatment in these populations in three studies. These studies were run at 54 sites in Australia, Europe, Israel, Japan, and north America, using a multicentre, single-arm design. Based on physiologically-based pharmacokinetic modelling predictions and EINSTEIN-Jr phase 1 data in young adults, a bodyweight-adjusted 20 mg-equivalent dose of rivaroxaban was given orally, in either a once-daily (tablets; for those aged 6–17 years), twice-daily (in suspension; for those aged 6 months to 11 years), or three times-daily (in suspension; for those younger than 6 months) dosing regimen for 30 days (or 7 days for those younger than 6 months). Treatment of children with bodyweight-adjusted rivaroxaban seemed to be safe in this study. In children with bodyweights of at least 30 kg and in children with bodyweights of at least 20 kg and less than 30 kg, therapeutic rivaroxaban exposures with once-daily dosing and with twice-daily dosing, respectively, were confirmed.