Rationale and design of a phase III safety trial of idarucizumab in children receiving dabigatran etexilate for venous thromboembolism

How I treat pediatric venous thromboembolism in the DOAC era

ABSTRACT

The direct oral anticoagulants (DOACs) rivaroxaban and dabigatran are newly licensed for the treatment and prevention of venous thromboembolism (VTE) in children and mark a renaissance in pediatric anticoagulation management. They provide a convenient option over standard-of-care anticoagulants (heparins, fondaparinux, and vitamin K antagonists) because of their oral route of administration, child-friendly formulations, and significant reduction in monitoring. However, limitations related to therapeutic monitoring when needed and the lack of approved reversal agents for DOACs in children raise some safety concerns. There is accumulating experience of safety and efficacy of DOACs in adults for a broad scope of indications; however, the cumulative experience of using DOACs in pediatrics, specifically for those with coexisting chronic illnesses, is sparse. Consequently, clinicians must often rely on their experience for treating VTE and extrapolate from data in adults while using DOACs in children. In this article, the authors share their experience of managing 4 scenarios that hematologists are likely to encounter in their day-to-day practice. Topics addressed include (1) appropriateness of indication; (2) use for special populations of children; (3) considerations for laboratory monitoring; (4) transition between anticoagulants; (5) major drug interactions; (6) perioperative management; and (7) anticoagulation reversal.

Albumin-Fusion Recombinant FIX in the Management of People with Hemophilia B: An Evidence-Based Review

Albutrepenonacog-alfa (Idelvion®, CSL Behring) is a recombinant fusion protein in which the recombinant FIX (rFIX) links a recombinant human albumin, extending the half-life of rFIX even beyond 100 hours. In 2016, this drug was approved worldwide for the treatment of pediatric and adult persons with hemophilia B (PWH-B). Its efficacy and safety were described in the PROLONG-9FP program and subsequently confirmed in the real-world practice, even if to date there are not many manuscripts that extensively and completely deal with the use of albutrepenonacog-alfa in daily practice, also evaluating its impact on the quality of life of patients treated with this drug; this review therefore aims to analyze all the publications currently available regarding the real-world use of this extended half-life concentrate, also noting which topics need further study and research.

Direct oral anticoagulants toxicity in children: an overview and practical guide

INTRODUCTION

By increasing use of direct oral anticoagulants (DOACs) in adults and children, gradual increase in the number of intentional or unintentional DOAC poisonings among children is suspected in the near future. Hence, clinicians and pharmacists need to be familiar with the clinical features and management of DOAC-toxicity among pediatric population.

AREAS COVERED

This article provides an overview and practical guide to DOAC-toxicity in pediatrics according to the available clinical evidence.

EXPERT OPINION

Based on limited available data, accidental pediatric ingestion of DOACs can be managed by supportive care in most cases. However, serious toxicity may occur following massive overdose, in presence of underlying disorders (renal or hepatic dysfunction) and concurrent anticoagulant therapy. Activated charcoal is recommended for known recent ingestion of DOACs (within 2-4 hours) to reduce the gastrointestinal absorption. Supportive interventions including local hemostatic measures and volume resuscitation are the cornerstone of management of bleeding. Vitamin K and fresh frozen plasma are ineffective for DOAC reversal and thus are not recommended. Currently, safety and efficacy data regarding the use of specific reversal agents (including idarucizumab and andexanet alfa) and 3-factor or 4-factor prothrombin complex concentrate (PCC) or activated PCC (aPCC) among children with DOAC-associated bleeding are lacking.

New Anticoagulants in Neonates, Children, and Adolescents

Thrombotic events are an increasing challenge in pediatrics. Standard-of-care anticoagulants for pediatric thrombosis have several disadvantages which could be overcome by using direct oral anticoagulants (DOACs). Until recently, there was not enough evidence from clinical trials to recommend for or against the use of any of the four DOACs in children with thrombosis. In this literature review, we looked at the latest clinical trials in this field. On clinicaltrials.gov, we found 13 current studies with published results. For two of the four DOACs, namely dabigatran and rivaroxaban, we found successful phase III studies which led to the approval for the use in children. The results of these pivotal phase III studies allow to finally recommend rivaroxaban and dabigatran for the prophylaxis and treatment of thrombotic events in children.

Andexanet Alfa Versus Prothrombin Complex Concentrates/Blood Products as Apixaban/Rivaroxaban Reversal Agents: A Survey Among Pediatric Hematologists

Direct oral factor Xa inhibitors (DXIs) are approved for use in adult patients with non-valvular heart disease for stroke prevention, and the treatment/prevention of venous thromboembolism (VTE). Recent pediatric clinical trials have demonstrated safety and efficacy of direct oral anticoagulants (DOACs) in the treatment of VTE. However, there is a lack of evidence regarding the use of andexanet alfa and prothrombin complex concentrates (PCC) for anticoagulation reversal of DXIs in the pediatric population. To better understand current DXI reversal strategies in this age group, a 10-question survey was conducted among pediatric hematology members of the Hemostasis and Thrombosis Research Society. Seventeen percent completed the survey (27 of 163 pediatric hematology members) with 74% (n = 20) reporting their use of DXIs for the treatment and prevention of VTE. Forty-four percent (n = 12) would choose andexanet alfa as first-line treatment for life-threatening bleeding while 52% (n = 14) would use PCC first with one individual choosing recombinant factor VII for DXI reversal. Clinical studies of andexanet alfa and PCC for the management of DXI-associated life-threatening bleeding require further investigation in the pediatric population.

Direct oral anticoagulants in pediatric venous thromboembolism: Review of approved products rivaroxaban and dabigatran

Venous thromboembolism is a major hospital acquired complication in the pediatric population over the last two-decades, with a 130% increase in the past decade. Direct oral anticoagulants (DOACs) are a newer class of anticoagulant medication for the treatment and prophylaxis of VTEs that provide the primary advantages of an oral route of administration without a requirement to adjust dosing to achieve a therapeutic level. It is anticipated that these medications will quickly replace parenteral anticoagulants and clinicians should familiarize themselves with DOACs. In this article, we provide an overview of the pharmacological properties of DOACs, with a specific focus on rivaroxaban and dabigatran, which have been approved for use in pediatric patients. Each drug's characteristics are discussed along with data from their respective clinical trials.

Switching patients in the age of long-acting recombinant products?

Introduction: Prophylaxis with factor replacement therapy is the gold standard for the treatment of hemophilia, but this often requires frequent infusions. A number of long-acting factor products have been developed to reduce the burden on patients. Areas covered: This is an overview of information presented at two symposia held at the World Federation of Hemophilia and International Society on Thrombosis and Haemostasis - Scientific and Standardization Committee annual meetings. The pharmacokinetic, safety and efficacy data for long-acting recombinant products are reviewed, with a focus on recombinant factor IX albumin fusion protein (rIX-FP) and rVIII-SingleChain. This overview also provides a guide for managing a patient's switch to long-acting products. Expert opinion: Long-acting products may allow patients to maintain or decrease bleeding rates whilst increasing their dosing interval, which may in turn reduce the burden on patients and caregivers. When switching patients to long-acting products health-care professionals should provide balanced and thorough education to the patient, whilst supporting their emotional well-being. Regimens should address patients' needs and goals but should also be guided by clinical phenotype and pharmacokinetic assessment. Follow-up should assess safety concerns, bleeding rates, joint health and the impact of the regimen on patients' lifestyle.