CC BY-NC-ND 4.0 · Thromb Haemost 2022; 122(09): 1573-1583
DOI: 10.1055/s-0042-1744542
Stroke, Systemic or Venous Thromboembolism

Anticoagulant Effects of Dabigatran on Coagulation Laboratory Parameters in Pediatric Patients: Combined Data from Five Pediatric Clinical Trials

Lesley G. Mitchell
1   Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
Daniel Röshammar
2   Pharmetheus AB, Uppsala, Sweden
Fenglei Huang
3   Translational Medicine and Clinical Pharmacology, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, Connecticut, United States
Manuela Albisetti
4   Hematology Department, University Children's Hospital, Zürich, Switzerland
Leonardo R. Brandão
5   Division of Hematology/Oncology, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
6   Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
Lisa Bomgaars
7   Department of Pediatrics, Texas Children's Cancer Center, Baylor College of Medicine, Houston, Texas, United States
Elizabeth Chalmers
8   The Glasgow Children's Haemophilia Unit, Royal Hospital for Children, Glasgow, Scotland, United Kingdom
Jacqueline Halton
9   Division of Hematology/Oncology, Children's Hospital of Eastern Ontario, University of Ottawa, Ottawa, Ontario, Canada
Matteo Luciani
10   Pediatric Hematology/Oncology Department, Pediatric Hospital Bambino Gesù, Rome, Italy
David Joseph
3   Translational Medicine and Clinical Pharmacology, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, Connecticut, United States
Igor Tartakovsky
11   Therapeutic Area Cardiovascular Medicine, Boehringer Ingelheim International GmbH, Ingelheim, Germany
Savion Gropper
12   Therapeutic Area Inflammation Medicine, Boehringer Ingelheim International GmbH, Ingelheim, Germany
Martina Brueckmann
11   Therapeutic Area Cardiovascular Medicine, Boehringer Ingelheim International GmbH, Ingelheim, Germany
13   Faculty of Medicine Mannheim of the University of Heidelberg, Mannheim, Germany
› Author Affiliations
Funding The study was supported by Boehringer Ingelheim International GmbH. Medical writing assistance, editorial, and technical support in the preparation of the manuscript was provided by Carolyn Bowler of Parexel and supported financially by Boehringer Ingelheim International GmbH.


Background Dabigatran etexilate, a direct oral thrombin inhibitor, is approved to treat venous thromboembolism (VTE) in both adults and children.

Objectives This population analysis characterized relationships between dabigatran total plasma concentrations and coagulation laboratory parameters (activated partial thromboplastin time [aPTT]; diluted thrombin time [dTT]; ecarin clotting time [ECT]).

Methods Data from three phase 2a and one single-arm and one randomized, comparative phase 2b/3 pediatric studies (measurements: aPTT 2,925 [N = 358]; dTT 2,348 [N = 324]; ECT 2,929 [N = 357]) were compared with adult data (5,740 aPTT, 3,472 dTT, 3,817 ECT measurements; N = 1,978). Population models were fitted using nonlinear mixed-effects modeling. Covariates (e.g., sex, age) were assessed on baseline and drug-effect parameters, using a stepwise covariate model-building procedure.

Results Overall, relationships between dabigatran, aPTT, dTT, and ECT were similar in children and adults. For children aged <6 months, a higher proportion of baseline samples were outside or close to the upper aPTT and ECT adult ranges. No age-related differences were detected for dTT. With increasing dabigatran concentration, aPTT rose nonlinearly (half the maximum effect at 368 ng/mL dabigatran) while dTT and ECT increased linearly (0.37 and 0.73% change per ng/mL dabigatran, respectively). Mean baseline aPTT (45 vs. 36 seconds) and ECT (40 vs. 36 seconds) were slightly increased for those aged <6 months versus older children.

Conclusion The similar relationships of laboratory parameters observed across pediatric age groups suggests that developmental changes in the hemostatic system may have little effect on response to dabigatran.

Author Contributions

L.G.M., D.R., F.H., and D.J., contributed to the concept, design, and analysis of the data. All authors contributed to critical writing or revising of intellectual content and final approval of the version to be published.

Trial Registrations identifiers: NCT00844415, NCT01083732, NCT02223260, NCT01895777, NCT02197416, NCT01688830, NCT01955720, NCT00291330, and NCT00657150.

Data Sharing Statement

To ensure independent interpretation of clinical study results and enable authors to fulfill their role and obligations under the ICMJE criteria, Boehringer Ingelheim grants all external authors access to relevant clinical study data. In adherence with the Boehringer Ingelheim Policy on Transparency and Publication of Clinical Study Data, scientific and medical researchers can request access to clinical study data after publication of the primary manuscript in a peer-reviewed journal, regulatory activities are complete and other criteria are met. Researchers should use the link to request access to study data and visit for further information.

Supplementary Material

Publication History

Received: 23 July 2021

Accepted: 10 February 2022

Article published online:
31 July 2022

© 2022. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (

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