Interim Results on the Impact of Rivaroxaban Dose Escalation on Recanalisation Time in Paediatric Patients with Venous Thromboembolism

Introduction: The increasing recognition of thromboembolic events in the paediatric population under the age of 14, particularly in younger children, has prompted a closer look at anticoagulation strategies [1]. Rivaroxaban, a novel oral anticoagulant, has shown promise; however, its standard dosing may not be optimal for all children [2]. Previous studies have shown that variations in body weight and age may influence pharmacodynamics and pharmacokinetics in paediatric patients, suggesting that higher doses may improve therapeutic efficacy while maintaining safety [3], due to developmental differences [4].

Aim of this study is to contribute to optimising paediatric anticoagulation therapy, pursued here by a comparison of the time to recanalisation in children receiving the standard dose of rivaroxaban with those receiving a higher dose.

Method: Our study included 48 paediatric patients with venous thromboembolism (VTE) from hospitals in North Rhine-Westphalia, Germany. The children were randomly assigned to two groups: 32 children received the standard dose and the remaining children an escalated dose, defined as the next higher dose in accordance with the instructions set forth in the Xarelto package leaflet.

Results: The majority were aged between one and three years, with 60.4% identified as male and 39.6% identified as female. The most prevalent form of VTE was sinus vein thrombosis (37.5%), followed by TVT and vena cava (both 18.8%). Of these diagnoses, 54.2% were given at birth, with the remaining 45.8% distributed almost evenly across the age groups up to 14 years. 45 out of the 48 individuals were surveyed for thrombophilia, with 28.9% identified as having thrombophilia and 71.1% as not having it. Among the 45, 17.8% displayed a factor V Leiden mutation, 13.3% factor V deficiency, 11.1% antithrombin deficiency, 6.7% prothrombin mutation, and 2.2% activated protein C resistance. 15.9% were heterozygous, 6.8% were homozygous, and 77.3% exhibited neither of these genotypes. 50% of patients achieved recanalisation, 10.4% achieved partial recanalisation, and 39.6% exhibited no recanalisation. Mean recanalisation time was 301 days (range 15–713 days), with a progressive increase with age, although with exceptions ([Fig. 1]). Foto number 1

Fig. 1  Time to recanalization according to age

Conclusion: Patients who underwent dose escalation exhibited notably shorter recanalisation times ([Fig. 2]). The finalised results are only available for the age range of one to three years, indicating that these findings are interim. Thus far, no other studies have demonstrated this age-related trend in recanalisation time.

Fig. 2  Time to recanalization according to dose and age

Foto number 2

Publication History

Article published online:
13 February 2025

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