Translation of a physiologically-based pharmacokinetic model for dabigatran etexilate to the design of a safety and efficacy study in post-partum women

Br J Clin Pharmacol. 2025 Nov 21. doi: 10.1002/bcp.70344. Online ahead of print.

Abstract

Aims: To translate a PBPK model developed for the direct oral anticoagulant, dabigatran etexilate, the prodrug of dabigatran, based on data obtained from healthy men to healthy non-pregnant, pregnant and post-partum women. To evaluate safety and efficacy of dabigatran etexilate in post-partum women using simulations and design a future clinical study to support model verification.

Methods: An integrated PBPK/PD model in healthy non-pregnant, pregnant and post-partum women was translated from the PBPK model in healthy men by capturing physiological changes. The model was also linked to established exposure-response relationships for coagulation indices and plasma-breast milk transfer using data from a pilot study. Finally, the model was used for simulation and the design of a prospective clinical study.

Results: The model predicted comparable plasma concentration profiles between healthy men and healthy, pregnant and post-partum women, by capturing their physiological differences. The model also captured plasma concentration and activated partial thromboplastin time (a coagulation index) data from a pilot study in post-partum women available in the literature. A sample size of 20 and 50-60 were determined to be appropriate for safety and efficacy arms respectively, of a clinical trial for model verification.

Conclusion: An integrated PBPK/PD model for dabigatran etexilate in post-partum women has been developed successfully. The model was used to design a future clinical trial examining safety and efficacy of dabigatran in postpartum women at risk of thromboembolism.

Keywords: dabigatran; modelling; pharmacokinetics; post‐partum women.