Dabigatran Etexilate in Children with Venous Thromboembolism: Results of the Open-Label, Phase IIb/III, Randomized Diversity Clinical Trial

Background: In children, current standard of care (SOC) with heparins or vitamin K antagonists is limited by the need for parenteral administration and frequent monitoring. Dabigatran etexilate (DE), a direct oral anticoagulant, is an effective oral treatment for venous thromboembolism (VTE) in adults and may be an effective and safe alternative to SOC for treating acute VTE in children. Aims: The DIVERSITY trial evaluated the efficacy and safety of DE versus SOC, and the appropriateness of a DE dosing algorithm, in children with VTE aged from birth to < 18 years. Methods: This was an open-label, randomized, active-controlled, multicenter, phase IIb/III trial (NCT01895777; consent obtained and ethics committee approved). Children (12 to < 18 years, 2 to < 12 years, birth to < 2 years) with an objectively confirmed VTE diagnosis and initially treated with unfractionated heparin or low-molecular-weight heparin were randomized (2:1) to DE (capsules, and child-friendly pellets and oral suspension, dosed using an age- and body-weight-adjusted dosing algorithm) or SOC, and treated for up to 3 months. The primary composite efficacy endpoint was the proportion of children with complete thrombus resolution, and freedom from recurrent VTE or VTE-related death. Safety endpoints included bleeding events and adverse events (AEs), and pharmacokinetic/pharmacodynamic (PK/PD) relationships. Results: Of 267 children in the randomized set, 35 were aged < 2 years (13 SOC, 22 DE; of these, 14 were < 6 months [3 SOC, 11 DE]), 64 were 2 to < 12 years (21 SOC, 43 DE), and 168 were 12 to < 18 years (56 SOC, 112 DE). Overall, similar proportions of children treated with SOC and DE met the composite efficacy endpoint (38/90 [42.2%] vs 81/177 [45.8%]; Mantel Hänszel-weighted difference -0.04; 90% confidence interval [CI] -0.14 to 0.07; p < 0.0001 for non-inferiority), and major bleeding events were comparable (2/90 [2.2%] and 4/176 [2.3%]; hazard ratio 0.94; 95% CI 0.17-5.16; p = 0.95). Across the three age groups (12 to < 18 years, 2 to < 12 years, birth to < 2 years), DE was comparable with SOC for the combined efficacy endpoint, which was achieved by 33.9-57.1% of children treated with SOC and 42.0-59.1% treated with DE. Similar numbers of children experienced major bleeding events, reported by between 0.0-3.6% of children treated with SOC and 1.8-4.5% treated with DE. In the overall population, the incidence of AEs in children treated with SOC and DE was 66.7% and 76.7%, respectively, and serious AEs were reported by 20.0% and 12.5% of all children, respectively. Across the three main age groups, the frequency of serious AEs was comparable for SOC and DE (reported by 19.0-23.1% and 9.1-14.4% of children, respectively). Dabigatran PK/PD relationships for three laboratory coagulation parameters (activated partial thromboplastin time [aPTT], diluted thrombin time [dTT], and ecarin clotting time [ECT]) were comparable across the three main age groups and were also similar in infants aged < 6 months (Figure). There was a linear relationship between total dabigatran plasma concentration for both dTT and ECT, and a nonlinear relationship with aPTT. These PK/PD relationships were similar to those observed in adults (data not shown). Conclusions: This randomized trial confirmed that an age- and weight-adjusted dabigatran dosing algorithm was appropriate in children aged from birth to < 18 yrs. Dabigatran, given as either capsules or child-friendly pellets or oral suspension, was comparable with SOC in terms of efficacy for acute VTE treatment across all age groups and, notably, in vulnerable children aged < 2 yrs. Disclosures Halton: Boehringer Ingelheim: Other: Member of a paediatric expert working group. Brandao:Boehringer Ingelheim: Other: Member of a paediatric expert working group. Luciani:Boehringer Ingelheim: Other: Member of a paediatric expert working group. Bomgaars:Boehringer Ingelheim: Other: Member of a paediatric expert working group. Chalmers:Shire/Takeda: Honoraria; CSL Behring: Honoraria; Bristol-Myers Squibb: Honoraria; Sobi: Honoraria; Roche: Honoraria; Grifols: Honoraria; Boehringer Ingelheim: Other: Member of a paediatric expert working group. Mitchell:Boehringer Ingelheim: Other: Member of a paediatric expert working group. Sharathkumar:Takeda: Consultancy; CSL Behring: Consultancy; Bayer: Consultancy; Kedrion: Consultancy. Svirin:Takeda: Consultancy, Other: Personal fees; CSL Behring: Consultancy, Other: Personal fees. Tartakovsky:Boehringer Ingelheim: Current Employment. Simetzberger:Boehringer Ingelheim: Current Employment. Huang:Boehringer Ingelheim: Current Employment. Sun:Boehringer Ingelheim: Current Employment. Kreuzer:Boehringer Ingelheim: Current Employment. Gropper:Boehringer Ingelheim: Current Employment. Brueckmann:Boehringer Ingelheim: Current Employment. Albisetti:Daiichi Sankyo: Membership on an entity's Board of Directors or advisory committees; Boehringer Ingelheim: Other: Member of a paediatric expert working group. OffLabel Disclosure: dabigatran etexilate in paediatric VTE

Download Full-text

Rationale and Design of a Phase IIb/III Open-Label, Multicenter Study of Dabigatran Etexilate for Venous Thromboembolism in Children: The Diversity Study

Blood ◽

10.1182/blood.v128.22.5025.5025 ◽

2016 ◽

Vol 128 (22) ◽

pp. 5025-5025

Author(s):

Manuela Albisetti ◽

Ivan Manastirski ◽

Martina Brueckmann ◽

Savion Gropper ◽

Bushi Wang ◽

...

Keyword(s):

Venous Thromboembolism ◽

Treatment Period ◽

Working Group ◽

Dabigatran Etexilate ◽

Plasma Concentrations ◽

Standard Of Care ◽

Open Label ◽

Safety And Efficacy ◽

Parenteral Treatment ◽

Expert Working Group

Abstract Background Venous thromboembolism (VTE) is increasing in children. The current standard of care comprises unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) for at least 5 days followed by UFH, LMWH or Vitamin K antagonists (VKA) for approximately 3 months in general. All of the current options have limitations: UFH and LMWH require parenteral administration; VKA requires frequent international normalized ratio (INR) monitoring and is associated with multiple food and drug interactions. The direct thrombin inhibitor, dabigatran, which is orally administered as the prodrug, dabigatran etexilate (DE) is effective for the treatment of VTE in adults and may overcome some of the limitations associated with standard of care. Objective To describe the design of a study evaluating the appropriateness of a proposed DE dosing algorithm and assessing the safety and efficacy of DE versus standard of care in pediatric patients with VTE. Methods This open-label, randomized, parallel-group, active-controlled, multi-center, non-inferiority study (NCT01895777) will be conducted in approximately 100 sites in approximately 30 countries. Patients aged 0 to < 18 years with an imaging-confirmed diagnosis of VTE initially receiving parenteral treatment with UFH or LMWH for 5-7 days (but no more than 21 days) who are expected to require anticoagulation therapy for at least 3 months will be eligible for inclusion. Main exclusion criteria include conditions associated with an increased risk of bleeding, renal dysfunction, active infective endocarditis, mechanical or biological heart valve prosthesis, hepatic disease and anemia or thrombocytopenia. Patients will be stratified into three age groups: stratum 1 (12 to < 18 years), stratum 2 (2 to < 12 years) and stratum 3 (birth to < 2 years). Recruitment will begin in stratum 1, being subsequently escalated to strata 2 and 3, respectively based on recommendations from the Data Monitoring Committee. Patients will be randomized (2:1) to receive DE versus standard of care (LMWH or VKA). DE will be administered twice daily as capsules, pellets or an oral liquid formulation depending on patient age and the patient's ability to swallow pellets or capsules. Upon completion of a 3-month treatment period (including the initial parenteral treatment phase) patients will be followed off-study drug for any adverse events. DE will be dosed to achieve steady-state measured trough circulating plasma concentrations (≥50 and < 250 ng/mL); the initial dose required will be calculated using a nomogram, which adjusts dosing according to the age and weight of the child. Dabigatran plasma concentrations will be evaluated at all study visits (7 scheduled during treatment period); DE will be up- or down-titrated as required. Results In terms of efficacy, the study will evaluate the proportion of patients with complete thrombus resolution, freedom from recurrent VTE (including symptomatic and asymptomatic, contiguous progression or non-contiguous new thrombus, deep vein thrombosis, pulmonary and paradoxical embolism, and thrombus progression) and freedom from VTE-related mortality. With regards to safety, the key endpoint will be freedom from major bleeding events, as per International Society on thrombosis and Haemostasis (ISTH) pediatric-specific criteria. All components of the primary efficacy and key safety endpoints will be adjudicated by an independent blinded committee. Conclusion This study, one of the largest controlled pediatric studies for VTE, will provide data on the safety and efficacy of DE compared with standard of care for the treatment of VTE in children aged 0 to < 18 years. Disclosures Albisetti: Boehringer Ingelheim: Other: Pediatric Expert Working Group. Manastirski:Boehringer Ingelheim: Employment. Brueckmann:Boehringer Ingelheim: Employment. Gropper:Boehringer Ingelheim: Employment. Wang:Boehringer Ingelheim: Employment. Tartakovsky:Boehringer Ingelheim: Employment. Biss:Boehringer Ingelheim: Employment. Huang:Boehringer Ingelheim: Employment. Mitchell:Boehringer Ingelheim: Consultancy; Pfizer: Consultancy; Bristol Myers Squibb: Consultancy. Halton:Boehringer Ingelheim: Other: Pediatric Expert Working Group for Boehringer Ingelheim.

Download Full-text

Pharmacokinetics (PK) and Pharmacodynamics (PD), Safety and Tolerability of a Single-Dose Oral Solution of Dabigatran Etexilate Given after Standard Anticoagulant Therapy in Children from Birth to Less Than One Year Old, with Venous Thromboembolism

Blood ◽

10.1182/blood.v128.22.1441.1441 ◽

2016 ◽

Vol 128 (22) ◽

pp. 1441-1441 ◽

Cited By ~ 3

Author(s):

Jacqueline ML Halton ◽

Anne-Caroline Picard ◽

Ruth Harper ◽

Fenglei Huang ◽

Martina Brueckmann ◽

...

Keyword(s):

Single Dose ◽

Venous Thromboembolism ◽

Plasma Concentration ◽

Treatment Period ◽

Working Group ◽

Dabigatran Etexilate ◽

Older Children ◽

Bleeding Events ◽

Expert Working Group ◽

Relationship Of

Abstract Background: Venous thromboembolism (VTE) events are more frequent in neonates than in children of other age groups. The standard of care for pediatric anticoagulation includes unfractionated or low-molecular-weight heparin, or vitamin K antagonists. However, these treatments have limitations in terms of practicality of use in infants, such as parenteral administration, frequent monitoring and drug interactions. Alternative oral agents that address these shortcomings may improve compliance, efficacy and safety. The safety and efficacy of dabigatran etexilate (DE), a direct thrombin inhibitor, are established in adults; pharmacokinetic/pharmacodynamic (PK/PD) studies indicate linear PK. There is a relationship between dabigatran plasma concentration (PK) and its PD effects, resulting in reproducible dose-dependent prolongation in clotting times with rapid onset and offset of effect, which is consistent across populations. Although phase IIa studies suggest a similar PK/PD relationship of dabigatran in children and adults, the hemostatic system in infants differs from older children and adults, which may lead to a different PK/PD effect. Objective: To demonstrate comparable PK/PD relationship of DE oral liquid formulation (OLF) between infants and older children and adults, and to assess safety and tolerability. Methods: Open-label, multicenter, single-dose, single-arm, phase IIa pediatric study. Infants aged < 1 year diagnosed with VTE who completed standard anticoagulant treatment for VTE were enrolled. Exclusion criteria included < 37 weeks gestational age at birth, weight < 3 kg, major bleed with standard anticoagulant and swallowing abnormalities. Patients received DE OLF (based on age- and weight-adjusted nomogram) and were followed up for 30 (+7) days. The primary endpoints were PK/PD related, measured at 2 hrs and 12 (±2) hrs after DE administration. The PK endpoint was plasma concentration of total dabigatran, and PD endpoints were activated partial thromboplastin time (aPTT), ecarin clotting time (ECT) and diluted thrombin time (dTT). Secondary endpoints included incidence of all bleeding events and adverse events (AEs), acceptability and tolerability. Descriptive statistics were applied to the endpoints. PK/PD relationship was analyzed using a simple linear regression model and nonlinear Emax model to confirm whether models used in previous studies were consistent with the pediatric data of this study. Results: Ten patients were screened and 8 entered the study (mean age [SD]: 89 [52] days; range: 41-169 days). Patients received a single dose of DE OLF. The geometric mean (gMean) total dabigatran plasma concentrations 2 hrs post dose (around peak concentrations) was 120 ng/mL with geometric coefficient of variation (gCV) of 62.1%, which indicated moderate variability. The gMean at 12 hrs post dosing was 60.4 ng/mL (gCV 30%), which indicated low variability. The projected steady-state dabigatran trough concentrations were largely comparable to those observed in adults with VTE (Table). A linear PK/PD relationship was observed for ECT (ECT ratio) and dTT (dTT ratio) (Figure). The relationship between total dabigatran concentration and aPTT (aPTT ratio) was nonlinear. The observed PK/PD relationships were similar to those in adult and adolescent patients with VTE, except for patients aged < 2 months, in whom a slight upward shift of aPTT of 10-20% (average) and ECT by 10-15% was observed relative to adults. There were no AEs, deaths or treatment discontinuations during the treatment period. None of the treated patients had any bleeding events or thromboembolic events during the study. One patient had a serious AE (aortic stenosis) during the post-treatment period, which was not considered treatment related by the investigator. There were no clinically relevant or unexpected laboratory findings. The majority of patients were assessed with good tolerability (six patients, 75%), and one patient each (12.5%) was evaluated with satisfactory or bad tolerability. Conclusion: In this small population of infants (aged < 1 year), DE OLF was well tolerated without any treatment-related AEs, thromboembolic or bleeding events. The observed PK/PD relationships were consistent with the established profile in adult and adolescent patients with VTE. Disclosures Halton: Boehringer Ingelheim: Other: Pediatric Expert Working Group for Boehringer Ingelheim. Picard:Boehringer Ingelheim: Employment. Harper:Boehringer Ingelheim: Employment. Huang:Boehringer Ingelheim: Employment. Brueckmann:Boehringer Ingelheim: Employment. Gropper:Boehringer Ingelheim: Employment. Maas:Boehringer Ingelheim: Employment. Tartakovsky:Boehringer Ingelheim: Employment. Nurmeev:Boehringer Ingelheim: Other: Investigator fees. Mitchell:Boehringer Ingelheim: Consultancy; Pfizer: Consultancy; Bristol Myers Squibb: Consultancy. Albisetti:Boehringer Ingelheim: Other: Pediatric Expert Working Group.

Download Full-text

Pharmacokinetics, Pharmacodynamics, Safety and Tolerability of a Single-Dose Oral Solution of Dabigatran Given after Standard Anticoagulant Therapy in Children (Two Age Groups: 1-<2 and 2-<12 Years Old), with Venous Thromboembolism

Blood ◽

10.1182/blood.v128.22.87.87 ◽

2016 ◽

Vol 128 (22) ◽

pp. 87-87 ◽

Cited By ~ 2

Author(s):

Jacqueline ML Halton ◽

Manuela Albisetti ◽

Matteo Luciani ◽

Fenglei Huang ◽

Branislav Biss ◽

...

Keyword(s):

Steady State ◽

Venous Thromboembolism ◽

Plasma Concentration ◽

Working Group ◽

Age Groups ◽

Study Drug ◽

Thrombin Time ◽

Bleeding Events ◽

Expert Working Group ◽

Trough Concentrations

Abstract Background: The incidence of venous thromboembolism (VTE) in children is increasing. The current standard of care is unfractionated heparin (UFH), low-molecular-weight heparin (LMWH) and Vitamin K antagonists (VKAs), all of which have limitations. Dabigatran, which is orally administered as the prodrug, dabigatran etexilate (DE), is effective for the treatment of VTE in adults and may overcome some of the limitations associated with standard care. Objective: The objectives of this phase IIa study were to obtain pharmacokinetic (PK) and pharmacodynamic (PD) data and to evaluate the tolerability and safety of an oral liquid formulation (OLF) of DE in patients aged 1 to < 12 years. Methods: The open-label, multinational, multicenter, non-randomized, single-arm study was conducted in patients aged 1 to < 2 years and 2 to < 12 years with a diagnosis of VTE, who had completed planned treatment with LMWH or oral anticoagulants (VKAs) for VTE. DE was administered as an OLF at a weight and age-adjusted dose (calculated using a nomogram) equivalent to 150 mg twice daily (bid) in adults. Originally, all patients were to receive multiple dosing (bid for 3 days). However, this was replaced with single dosing (SD) in the course of the study. A 30-day follow-up was included. Here we report data from SD patients only. The primary PK endpoints were plasma concentration of total dabigatran, free dabigatran, unchanged DE and intermediate metabolites. To compare the exposure to DE in pediatrics with that in adults with VTE, gMean concentrations at 10 hours after SD of DE were extrapolated to steady-state trough concentration. An accumulation ratio was calculated based on the terminal half-life (t1/2) and the dosing interval (for a bid dosing regimen) to project the steady-state dabigatran plasma concentration. Primary PD endpoints were activated partial thromboplastin time (aPTT), ecarin clotting time (ECT), and diluted thrombin time (dTT). Primary safety endpoints were incidence of all bleeding events and incidence of all adverse events (AEs). Results: Six patients aged 1 to < 2 years and 9 patients aged 2 to < 12 years received SD DE; 3 patients aged 2 to < 12 received multiple doses (bid for 3 days). In the SD groups, plasma concentration of total dabigatran increased at 2 hours (peak) after dosing then decreased until 10 hours after dosing. The projected steady-state dabigatran trough concentrations of both age groups of children studied were largely comparable to those observed in adults with VTE, i.e. the projected results for children fell between the first and the third quartile of adult trough concentrations (Table). Data from the SD groups indicated that there was a linear PK/PD relationship for ECT and dTT (see Figure) and a non-linear PK/PD relationship for aPTT. The PK/PD relationships were similar to those seen in adults (for all coagulation parameters analyzed) and adolescents (dTT and ECT) with VTE. During the on-treatment period there were no study drug related AEs; one patient had AEs (leukopenia and dizziness), which were mild in intensity and unrelated to the study drug. No AEs were reported during the post-treatment or post-study periods. No bleeding events were reported. Conclusion: The OLF of DE was well tolerated in pediatrics, with no drug-related AEs or bleeding events. Projected steady-state dabigatran trough concentrations were largely comparable to those seen in adults with VTE. The observed PK/PD relationship was similar to that seen in adults and adolescents with VTE. Disclosures Halton: Boehringer Ingelheim: Other: Pediatric Expert Working Group for Boehringer Ingelheim. Albisetti:Boehringer Ingelheim: Other: Pediatric Expert Working Group. Luciani:Boehringer Ingelheim: Other: Member of Pediatric Expert Working Group for Boehringer Ingelheim. Huang:Boehringer Ingelheim: Employment. Biss:Boehringer Ingelheim: Employment. Brueckmann:Boehringer Ingelheim: Employment. Gropper:Boehringer Ingelheim: Employment. Maas:Boehringer Ingelheim: Employment. Tartakovsky:Boehringer Ingelheim: Employment. Mitchell:Boehringer Ingelheim: Consultancy; Pfizer: Consultancy; Bristol Myers Squibb: Consultancy.

Download Full-text

Safety of dabigatran etexilate for the secondary prevention of venous thromboembolism in children

Blood ◽

10.1182/blood.2019000998 ◽

2020 ◽

Vol 135 (7) ◽

pp. 491-504 ◽

Cited By ~ 10

Author(s):

Leonardo R. Brandão ◽

Manuela Albisetti ◽

Jacqueline Halton ◽

Lisa Bomgaars ◽

Elizabeth Chalmers ◽

...

Keyword(s):

Risk Factor ◽

Venous Thromboembolism ◽

Dabigatran Etexilate ◽

Standard Of Care ◽

Central Line ◽

Clinical Risk Factor ◽

Postthrombotic Syndrome ◽

Minor Bleeding ◽

Bleeding Events ◽

Open Label

Abstract This open-label, single-arm, prospective cohort trial is the first phase 3 safety study to describe outcomes in children treated with dabigatran etexilate for secondary venous thromboembolism (VTE) prevention. Eligible children aged 12 to <18 years (age stratum 1), 2 to <12 years (stratum 2), and >3 months to <2 years (stratum 3) had an objectively confirmed diagnosis of VTE treated with standard of care (SOC) for ≥3 months, or had completed dabigatran or SOC treatment in the DIVERSITY trial (NCT01895777) and had an unresolved clinical thrombosis risk factor requiring further anticoagulation. Children received dabigatran for up to 12 months, or less if the identified VTE clinical risk factor resolved. Primary end points included VTE recurrence, bleeding events, and mortality at 6 and 12 months. Overall, 203 children received dabigatran, with median exposure being 36.3 weeks (range, 0-57 weeks); 171 of 203 (84.2%) and 32 of 203 (15.8%) took capsules and pellets, respectively. Overall, 2 of 203 children (1.0%) experienced on-treatment VTE recurrence, and 3 of 203 (1.5%) experienced major bleeding events, with 2 (1.0%) reporting clinically relevant nonmajor bleeding events, and 37 (18.2%) minor bleeding events. There were no on-treatment deaths. On-treatment postthrombotic syndrome was reported for 2 of 162 children (1.2%) who had deep vein thrombosis or central-line thrombosis as their most recent VTE. Pharmacokinetic/pharmacodynamic relationships of dabigatran were similar to those in adult VTE patients. In summary, dabigatran showed a favorable safety profile for secondary VTE prevention in children aged from >3 months to <18 years with persistent VTE risk factor(s). This trial was registered at www.clinicaltrials.gov as #NCT02197416.

Download Full-text

Influence Of Age On The Efficacy and Safety Of Dabigatran Versus Warfarin For The Treatment Of Acute Venous Thromboembolism: A Pooled Analysis Of RE-Cover and RE-Cover II

Blood ◽

10.1182/blood.v122.21.2375.2375 ◽

2013 ◽

Vol 122 (21) ◽

pp. 2375-2375 ◽

Cited By ~ 6

Author(s):

Sam Schulman ◽

Henry Eriksson ◽

Samuel Z Goldhaber ◽

Ajay Kakkar ◽

Clive Kearon ◽

...

Keyword(s):

Venous Thromboembolism ◽

Research Funding ◽

Dabigatran Etexilate ◽

Age Groups ◽

Age Group ◽

Parenteral Therapy ◽

Bleeding Events ◽

Advisory Boards ◽

Bayer Healthcare ◽

Recurrent Vte

Abstract Background In the RE-COVER and RE-COVER II trials, a fixed dose of dabigatran etexilate was as effective as warfarin for prevention of recurrent VTE and was associated with a lower risk of bleeding. It is not known whether this efficacy and difference in bleeding rates is maintained in older patients. Objectives Older patients may be at greater risk of bleeding and/or VTE. Therefore, we performed a subgroup analysis on the pooled RE-COVER and RE-COVER II trial results to investigate the efficacy and safety of dabigatran versus warfarin for the treatment of acute VTE according to age. Methods Patients with acute VTE received parenteral anticoagulation and were randomized to the addition of warfarin or warfarin-placebo for at least 5 days until the international normalized ratio (INR) was ≥ 2 at two consecutive measurements. This was followed (on discontinuation of parenteral therapy) by continued warfarin (target INR range 2.0–3.0) or dabigatran 150 mg twice daily (double dummy; “oral only” treatment period) for 6 months. Outcomes were centrally adjudicated. The primary efficacy outcome was recurrent, symptomatic, objectively confirmed VTE or VTE-related death from randomization (i.e., start of parenteral therapy plus either warfarin or warfarin-placebo) up to the end of the prespecified post-treatment follow-up. Major bleeding events (MBEs), the composite of MBEs or clinically relevant non-major bleeding events (CRBEs), and any bleeds were counted from the start of the double-dummy period (treatment with oral dabigatran or warfarin alone) up to the end of the 6-month study period. Thus, the safety analysis excludes events associated with parenteral therapy either in combination with warfarin or with warfarin-placebo prior to commencing dabigatran treatment; it therefore compares dabigatran with warfarin at its full pharmacological potential. Results Of 2553 patients randomized to dabigatran, 68 (2.7%) had recurrent VTE or VTE-related death compared with 62 (2.4%) of 2554 patients randomized to warfarin; hazard ratio (HR) 1.09 (95% CI 0.77, 1.54). The incidences of the primary efficacy outcome (dabigatran vs warfarin) by age group were 3.0% (53/1769) versus 2.4% (42/1748) for patients < 65, 2.3% (12/531) versus 2.5% (13/530) for patients 65–75, and 1.2% (3/253) versus 2.5% (7/276) for patients > 75 years; and in a second age-group comparison were 2.8% (67/2418) vs 2.3% (57/2429) for patients < 80 and 0.7% (1/135) versus 4.0% (5/125) for patients ≥ 80 years. Cox regression analysis showed no statistically significant interaction, indicating that there are similar treatment effects across age groups. MBEs were significantly less frequent with dabigatran than with warfarin overall (HR 0.60; 95% CI 0.36, 0.99). Incidences by age group are shown in the Table. MBE/CRBE incidence was also significantly lower with dabigatran versus warfarin overall (HR 0.56; 95% CI 0.45, 0.71). The Table shows event rates for each age group. Similarly, any bleeding events were significantly less frequent with dabigatran than with warfarin overall. There was no significant treatment-by-age interaction for MBEs or MBEs/CRBEs or any bleeds in either analysis. Conclusions No differences in recurrent VTE or efficacy were apparent across the age groups. Bleeding events increased with increasing age but numerically were similar or lower with dabigatran than with warfarin regardless of age. The results suggest there is no need for dose adjustment of dabigatran according to age for the treatment of VTE. Disclosures: Schulman: Bayer Healthcare: Consultancy, Honoraria, Research Funding; Boehringer Ingelheim: Consultancy, Honoraria, Research Funding. Off Label Use: Dabigatran etexilate is an oral direct thrombin inhibitor approved for the prevention of stroke in patients with atrial fibrillation and (outside the US) for prevention of venous thromboembolism in patients undergoing total hip or knee replacement. This presentation includes discussion of the following off-label use of dabigatran: treatment of venous thromboembolism. Eriksson:Boehringer Ingelheim: Consultancy; BMS: Consultancy; Pfizer: Consultancy. Goldhaber:Boehringer Ingelheim: Consultancy; Daiichi: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Janssen: Consultancy; Merck: Consultancy; Pfizer: Consultancy; Portola: Consultancy; Sanofi-Aventis: Consultancy. Kakkar:Boehringer Ingelheim: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria, Research Funding; BMS: Consultancy, Honoraria, Research Funding; Daiichi: Consultancy, Honoraria, Research Funding; Bayer: Consultancy, Honoraria, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding; Eisai Inc: Consultancy, Honoraria, Research Funding. Kearon:Bayer Healthcare Inc. : Consultancy; Boehringer Ingelheim (Canada) Ltd./Ltée : Consultancy. Schellong:Boehringer Ingelheim: Advisory Boards Other, Consultancy, Honoraria; Bayer Healthcare: Advisory Boards, Advisory Boards Other, Consultancy, Honoraria; BMS/Pfizer: Honoraria; Daiichi Sankyo: Advisory Boards, Advisory Boards Other, Honoraria. Kreuzer:Boehringer Ingelheim: Employment. Peter:Boehringer Ingelheim: Employment. Friedman:Boehringer Ingelheim: Employment.

Download Full-text

Efficacy and Safety of Dabigatran in the Treatment and Secondary Prophylaxis of Children with Venous Thromboembolism and Thrombophilia

Blood ◽

10.1182/blood-2020-136695 ◽

2020 ◽

Vol 136 (Supplement 1) ◽

pp. 35-36

Author(s):

Leonardo R. Brandao ◽

Igor Tartakovsky ◽

Manuela Albisetti ◽

Lisa Bomgaars ◽

Elizabeth Chalmers ◽

...

Keyword(s):

Clinical Trials ◽

Risk Factor ◽

Working Group ◽

Dabigatran Etexilate ◽

Secondary Prophylaxis ◽

Efficacy And Safety ◽

Open Label ◽

Expert Working Group ◽

Open Label Phase ◽

Favorable Safety

Background: Thrombophilia in children is characterized by hypercoagulability and increased frequency of thrombotic events (Young G, et al. Circulation. 2008;118:1373-1378; Kenet G, et al. Circulation. 2010;121:1838-1847). Recently, phase IIb/III clinical trials in children with venous thromboembolism (VTE) have reported the non-inferiority of dabigatran etexilate (DE) versus standard of care (SOC) for the treatment of acute VTE (Albisetti M, et al. ISTH 2019, Abstract OC 57.3), and a favorable safety profile for DE in secondary VTE prevention in children with persistent VTE risk factor(s) (Brandão LR, et al. Blood. 2020;135:491-504). Aims: To perform a subgroup analysis evaluating the efficacy and safety of DE for the treatment and secondary prophylaxis of VTE in children with thrombophilia in the phase IIb/III DE clinical trials. Methods: In the open-label, phase IIb/III DIVERSITY trial (NCT01895777), children aged from birth to < 18 years (yrs) with an objectively confirmed VTE diagnosis (by imaging studies) initially treated with unfractionated heparin or low-molecular-weight heparin were randomized (2:1) to receive up to 3 months of DE or SOC. Primary composite efficacy endpoint: complete thrombus resolution and freedom from VTE recurrence, or VTE-related death. Safety endpoints included bleeding events (BEs). The open-label, phase III, secondary VTE prevention trial (NCT02197416) treated children aged from > 3 months to < 18 yrs with DE for up to 12 months or less, if the identified VTE clinical risk factor resolved. Eligible children had an objectively confirmed diagnosis of VTE treated with SOC for ≥ 3 months, or had completed DE or SOC treatment in DIVERSITY and had an unresolved clinical VTE risk factor requiring further anticoagulation. Primary endpoints included VTE recurrence and BEs. Thrombophilia status was confirmed according to the definitions used by the local experts. Results: In DIVERSITY, 23.2% of children had thrombophilia; demographics were comparable to the overall population, although they were slightly older (mean [standard deviation] age 13.2 [4.9] vs 11.1 [6.1] years in the overall population; p = 0.005). In children with thrombophilia, DE was found to be non-inferior to SOC for the primary endpoint (similar to the overall population), and more children treated with DE achieved the composite primary endpoint than with SOC (SOC 21.7% vs DE 35.9%; Mantel-Hänszel-weighted difference in rates for SOC minus DE [90% CI] −0.14 [−0.32 to 0.05]; p for non-inferiority = 0.0014), similar to the overall population (Table). Regardless of treatment, VTE recurrence appeared higher in children with thrombophilia than in the overall population, with numerically fewer VTE recurrences reported by children with thrombophilia treated with DE (7.7%) versus SOC (21.7%), although this was not significantly lower (p = 0.13). Numerical differences in residual thrombotic burden between SOC vs DE seen in the overall population appeared to be amplified in children with thrombophilia. Numerically fewer children with thrombophilia treated with DE reported thrombus progression (SOC 13.0% vs DE 5.1%) or stabilization (21.7% vs 10.3%), while more reported partial (34.8% vs 43.6%) or complete thrombus resolution (21.7% vs 35.9%). In the thrombophilia subgroup, BEs appeared to be lower in children treated with DE (SOC 26.1% vs DE 17.9%), while in the overall population BEs with SOC and DE were comparable. In the secondary VTE prevention trial, children with thrombophilia were also slightly older versus the overall population (mean [standard deviation] age 14.1 [3.6] vs 12.8 [4.6] yrs; p = 0.006). In this larger subgroup of children, rates of recurrent VTE at 12 months appeared to be higher in the thrombophilia group (2.8%) compared to the overall population (1.4%) (Table), with BEs largely comparable (27.4% and 22.5%, respectively). Conclusions: Unsurprisingly, numerically more children with thrombophilia appeared to report VTE recurrence, and in DIVERSITY thrombus progression/stabilization also seemed higher compared with the overall population. Compared with the overall populations, these subgroup analyses showed consistent results for DE in children with acute VTE and thrombophilia in the DIVERSITY trial, along with a favorable safety profile of DE for secondary VTE prevention. Disclosures Brandao: Boehringer Ingelheim: Other: Member of a paediatric expert working group. Tartakovsky:Boehringer Ingelheim: Current Employment. Albisetti:Boehringer Ingelheim: Other: Member of a paediatric expert working group; Daiichi Sankyo: Membership on an entity's Board of Directors or advisory committees. Bomgaars:Boehringer Ingelheim: Other: Member of a paediatric expert working group. Chalmers:CSL Behring: Honoraria; Shire/Takeda: Honoraria; Boehringer Ingelheim: Other: Member of a paediatric expert working group; Grifols: Honoraria; Roche: Honoraria; Sobi: Honoraria; Bristol-Myers Squibb: Honoraria. Mitchell:Boehringer Ingelheim: Other: Member of a paediatric expert working group. Luciani:Boehringer Ingelheim: Other: Member of a paediatric expert working group. Lvova:Boehringer Ingelheim: Honoraria. Simetzberger:Boehringer Ingelheim: Current Employment. Sun:Boehringer Ingelheim: Current Employment. Gergei:Boehringer Ingelheim: Current Employment. Brueckmann:Boehringer Ingelheim: Current Employment. Halton:Boehringer Ingelheim: Other: Member of a paediatric expert working group. OffLabel Disclosure: dabigatran etexilate in paediatric VTE

Download Full-text

Rationale and Design of a Phase III Single-Arm Multicenter Study of Dabigatran Etexilate for the Secondary Prevention of Venous Thromboembolism in Children

Blood ◽

10.1182/blood.v128.22.5028.5028 ◽

2016 ◽

Vol 128 (22) ◽

pp. 5028-5028

Author(s):

Matteo Luciani ◽

Manuela Albisetti ◽

Ivan Manastirski ◽

Martina Brueckmann ◽

Savion Gropper ◽

...

Keyword(s):

Risk Factor ◽

Steady State ◽

Venous Thromboembolism ◽

Secondary Prevention ◽

Working Group ◽

Dabigatran Etexilate ◽

Phase Iii ◽

Clinical Risk Factor ◽

Clinical Risk ◽

Expert Working Group

Abstract Background: In children, the incidence of venous thromboembolism (VTE) is increasing and is often associated with underlying diseases such as cancer, or risk factors such as thrombophilia. Following treatment for acute VTE, thrombosis or thromboembolic events can recur particularly if a clinical risk factor for VTE persists. The efficacy and safety of the oral anticoagulant dabigatran etexilate (DE) have been demonstrated in a number of thrombosis-related indications in adults, including for secondary VTE-prevention. There are, however, potential differences between adults and children related to developmental physiology and pharmacology and therefore trials to evaluate the pharmacokinetics (PK), pharmacodynamics (PD) and safety of DE in children are required. To date, all pediatric phase IIa studies conducted have shown a similar PK and PK/PD relationship of DE in comparison to adult studies. Objective: To describe the design of a study to evaluate the safety and PK-PD of DE for secondary prevention of VTE in children aged 0-<18 years. Methods: This phase III, open-label, single-arm, multicenter study will be conducted at ~100 sites worldwide (NCT02197416). Eligible patients will have completed a course of initial treatment for confirmed acute VTE (for ≥ 3 months) and be considered at high risk for VTE recurrence due to the remaining presence of a clinical risk factor. Approximately 100 subjects between 0-<18 years of age will be included. Treatment with DE will extend up to 12 months, or less if the clinical risk factor resolves, with a follow-up visit 28 days after the last dose. DE will be administered twice daily as capsules, pellets or oral liquid formulation, depending on subject age and their ability to swallow capsules or pellets. A dosing nomogram will be used to scale down an adult dose based on the child's age and weight. Initial doses calculated using the nomogram should achieve steady-state trough concentrations of DE of between 50 and < 250 ng/ml, a range which is assumed to result in safe and effective use of DE in this pediatric population; after about 3 days, trough dabigatran plasma concentration will be measured and DE may be titrated up or down to achieve the target steady-state trough plasma concentration. Results: Demographic and medical history data will be collected for all participants. The primary outcomes to be evaluated are instances at 6 and 12 months of image-proven VTE recurrence; major and minor bleeding, including clinically relevant non-major bleeding; and overall and thrombotic/thromboembolic mortality. All elements of the primary endpoints will be evaluated by an independent adjudication committee that will confirm or refute outcome events. The secondary outcomes are rates of post-thrombotic syndrome at 6 and 12 months; PK and PD (e.g., activated partial thromboplastin time and ecarin clotting time); and the number of DE dose adjustments required during the treatment period. Data on the acceptability of the age-appropriate drug formulation, the tolerability of the study medication, adverse events, treatment discontinuations due to an adverse event, and laboratory and clinical parameters will also be collected during the study. Safety and tolerability will be monitored by the independent Data Monitoring Committee. Conclusion: This phase III study has been designed to provide data on the safety and PK-PD of DE for the secondary prevention of VTE in children aged 0-<18 years. Disclosures Luciani: Boehringer Ingelheim: Other: Member of Pediatric Expert Working Group for Boehringer Ingelheim. Albisetti:Boehringer Ingelheim: Other: Pediatric Expert Working Group. Manastirski:Boehringer Ingelheim: Employment. Brueckmann:Boehringer Ingelheim: Employment. Gropper:Boehringer Ingelheim: Employment. Tartakovsky:Boehringer Ingelheim: Employment. Wang:Boehringer Ingelheim: Employment. Biss:Boehringer Ingelheim: Employment. Mitchell:Bristol Myers Squibb: Consultancy; Pfizer: Consultancy; Boehringer Ingelheim: Consultancy. Huang:Boehringer Ingelheim: Employment. Halton:Boehringer Ingelheim: Other: Pediatric Expert Working Group for Boehringer Ingelheim.

Download Full-text

Apixaban versus Warfarin in Patients with Left Ventricular (LV) Thrombus, a prospective randomized trial

European Heart Journal ◽

10.1093/ehjci/ehaa946.1545 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

R Alcalai ◽

R Rashad ◽

A Butnaru ◽

G Moravsky ◽

D Leibowitz

Keyword(s):

Major Bleeding ◽

Thrombus Formation ◽

Oral Anticoagulants ◽

Direct Oral Anticoagulants ◽

Left Ventricular ◽

Systemic Embolism ◽

Bleeding Events ◽

Open Label ◽

Warfarin Group ◽

Acute Mi

Abstract Background Patients with acute myocardial infarction (MI) have an elevated risk of stroke, mostly due to left ventricular (LV) thrombus formation, which typically occur within the first 2 weeks following an anterior MI. Currently the recommended management of LV thrombus after acute MI is anticoagulation with vitamin K antagonist. To date, there are no prospective data on the use of direct oral anticoagulants (DOACS) for stroke prevention in the setting of LV thrombus. Aim To assess the efficacy of apixaban vs. warfarin in treating LV thrombus after MI. Methods The study is a prospective, randomized, multi-center open label trial comparing apixaban (at a dose of 5 mg twice daily) with s.c enoxaparin 1mg/kg BID followed by dose-adjusted warfarin to achieve a target international normalized ratio (INR) of 2.0 to 3.0 for 3 months in patients with LV thrombus detected by echocardiography 3 to 14 days after acute MI. The primary outcome was the presence and size of LV thrombus 3 months after initiation of anticoagulation as assessed by 2D echocardiogram. Secondary outcomes were stroke or systemic embolism, major bleeding and death from any cause. Results 25 patients have been enrolled to date in 3 medical centers, 13 were randomized to apixaban and 12 to warfarin. Mean age was 59.8±10.7 and 19 (76%) were males with no difference between the study groups. Mean LV thrombus size at enrollment was 24X15 mm in the apixaban group and 19X14 in the warfarin group (p=NS). After 3 months of treatment thrombus completely resolved in all patients in the warfarin group and in 12 of 13 in the apixaban group. In one patient in the apixaban group who had a very large thrombus of 40x20mm size upon enrollment the thrombus size was reduced significantly to 20x12 after 3 months. No death, stroke or systemic embolism was documented in either group. There were two patients with major bleeding in the warfarin group, one had sub-arachnoid hemorrhage after 2 months and anticoagulation was stopped, and another had GI bleeding after 1 month and was switched to enoxaparin. One patient in the warfarin group refused to continue the treatment after 3 weeks. No major bleeding events were recorded in the apixaban group and all patients completed 3 months of treatment. Conclusions Our preliminary results indicate that apixaban is a safe and effective treatment for patients with LV thrombus post anterior wall MI. Funding Acknowledgement Type of funding source: None

Download Full-text

INNV-10. SAFETY OF APIXABAN FOR VENOUS THROMBOEMBOLISM PREVENTION IN PATIENTS WITH NEWLY DIAGNOSED GLIOBLASTOMA

Neuro-Oncology ◽

10.1093/neuonc/noz175.553 ◽

2019 ◽

Vol 21 (Supplement_6) ◽

pp. vi132-vi132

Author(s):

Alissa Thomas ◽

Heather Wright ◽

Hannah Walker ◽

Prachi Prasad ◽

Kelly Chan ◽

...

Keyword(s):

Venous Thromboembolism ◽

Standard Of Care ◽

High Risk Group ◽

Prevention Strategy ◽

Newly Diagnosed ◽

Bleeding Events ◽

Open Label ◽

Effective Prevention ◽

Vte Prophylaxis ◽

Venous Thromboembolism Prevention

Abstract Venous thromboembolism (VTE) impacts an estimated one in every three patients with malignant glioma (MG), resulting in increased morbidity and mortality. Despite the high prevalence and serious consequences of VTE, there is no outpatient standard of care prevention strategy. There have been three prospective clinical trials of VTE prophylaxis in patients with newly diagnosed MG, all of which used an injectable low molecular weight heparin (LMWH) product. We performed an open-label safety study of apixaban, a direct oral anticoagulant (DOAC), for VTE prevention in patients with newly diagnosed MG. All patients had surgery or biopsy two to twenty-one days prior to enrollment in the study. Patients were treated with apixaban 2.5 mg twice daily for up to 6 months. Peak and trough apixaban concentrations were measured at the beginning and end of treatment. Thirteen patients consented to the study and ten enrolled (2 screen-fail, 1 withdrawal). The patients have completed a mean of 4.5 cycles of apixaban (range 2 to 6, with 2 patients still undergoing treatment). There were no bleeding events while receiving apixaban. There were no hematologic or non-hematologic treatment-related adverse events. There were no VTE events observed in patients receiving apixaban. Two patients who came off treatment early due to disease progression developed VTEs after stopping prophylactic apixaban. Quality of life analysis is ongoing. In this pilot study we found that prophylactic dosing of 2.5 mg twice daily of apixaban was safe in the post-operative period for patients with newly diagnosed MG. Our preliminary results suggest that this may be a safe and effective prevention strategy for VTE prophylaxis in this high risk group of patients.

Download Full-text

Risk of major bleeding during extended oral anticoagulation in patients with first unprovoked venous thromboembolism: a systematic review and meta-analysis protocol

Systematic Reviews ◽

10.1186/s13643-019-1175-5 ◽

2019 ◽

Vol 8 (1) ◽

Cited By ~ 1

Author(s):

Faizan Khan ◽

Miriam Kimpton ◽

Tobias Tritschler ◽

Grégoire Le Gal ◽

Brian Hutton ◽

...

Keyword(s):

Systematic Review ◽

Venous Thromboembolism ◽

Anticoagulant Therapy ◽

Major Bleeding ◽

Oral Anticoagulation ◽

Meta Analysis ◽

Controlled Trials ◽

Bleeding Events ◽

Major Bleeding Events

Abstract Background The optimal duration of anticoagulation after a first unprovoked venous thromboembolism (VTE) remains controversial. Deciding to stop or continue anticoagulant therapy indefinitely after completing 3 to 6 months of initial treatment requires balancing the long-term risk of recurrent VTE if anticoagulation is stopped against the long-term risk of major bleeding if anticoagulation is continued. However, knowledge of the long-term risk for major bleeding events during extended anticoagulation in this patient population is limited. We plan to conduct a systematic review and meta-analysis to quantify the risk for major bleeding events during extended oral anticoagulation in patients with first unprovoked VTE. Methods Electronic databases including MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials will be systematically searched with the assistance of an information specialist (from inception to March 1, 2019) to identify randomized controlled trials and prospective cohort studies reporting major bleeding during extended oral anticoagulation in patients with first unprovoked VTE, who have completed at least 3 months of initial anticoagulant therapy. Study selection, risk of bias assessment, and data extraction will be performed independently by at least two investigators. The number of major bleeding events and person-years of follow-up will be used to calculate the rate (events per 100 person-years) with its 95% confidence interval for each study cohort, during clinically relevant time periods of extended anticoagulant therapy. Results will be pooled using random effect meta-analysis. Discussion The planned systematic review and meta-analysis will provide reliable estimates of the risk for major bleeding events during extended anticoagulation. This information will help inform patient prognosis and assist clinicians with balancing the risks and benefits of treatment to guide management of unprovoked VTE. Systematic review registration PROSPERO CRD42019128597.

Download Full-text