Diagnostic Accuracy of a Novel Chromogenic Direct Thrombin Inhibitor Assay: Clinical Experiences for Dabigatran Monitoring

Background  Direct oral anticoagulants (DOACs) are increasingly replacing vitamin K antagonists (VKA) for clinical indications requiring long-term oral anticoagulation. In contrast to VKA, treatment with DOAC including dabigatran—the only direct thrombin inhibitor amongst them—does not require therapeutic drug monitoring. However, in case of treatment complications (e.g., major haemorrhage) and conditions requiring urgent surgery or thrombolytic therapy, information about actual DOAC plasma levels is needed to guide treatment decisions. Due to short reagent stability, limited accuracy at low dabigatran levels and high heparin sensitivity, the applicability of the widely used Hemoclot thrombin inhibitor (HTI) coagulation assay is limited in the emergency setting. Methods  Dabigatran concentrations of 288 citrated plasma samples taken from 48 dabigatran-treated patients with drug concentrations of up to 300 ng/mL were measured with the chromogenic anti-IIa Biophen direct thrombin inhibitor (BDTI) assay and results compared with HTI using ultra performance liquid chromatography—tandem mass spectrometry as the reference method for measuring dabigatran plasma concentrations. Results  BDTI results showed a very strong correlation with dabigatran concentrations ( r  = 0.965, p Conclusion  The BDTI is an ideal coagulation assay for the around-the-clock determination of dabigatran plasma levels in clinical routine including emergency situations.