Comparison of analytical performances between clot waveform analysis and FibWave in edoxaban-treated patients and healthy controls.

Introduction: The activated partial thromboplastin time (aPTT) and the prothrombin time (PT) are widely available coagulation parameters which are however poor predictors of the anticoagulant effect of direct oral anticoagulants (DOACs). Some coagulometers use the clot waveform analysis (CWA) to assess the clotting time but mainly based on a unique parameter. The improvement of these methodologies and the evaluation of the other waveform parameters may increase the sensitivity to DOACs.

Performance of a Qualitative Point-of-Care Strip Test to Detect DOAC Exposure at the Emergency Department: A Cohort-Type Cross-Sectional Diagnostic Accuracy Study.

An accurate point-of-care test for detecting effective anticoagulation by direct oral anticoagulants (DOACs) in emergencies is an unmet need. We investigated the accuracy of a urinary qualitative strip test (DOAC Dipstick) to detect relevant DOAC exposure in patients who presented to an emergency department. In this prospective single-center cohort-type cross-sectional study, adults on DOAC treatment were enrolled.

The edoxaban-M4 metabolite and measurement of edoxaban by chromogenic assays in human plasma.

Introduction: Edoxaban is the only anti-Xa inhibitor metabolized in pharmacologically active moiety that could interfere with chromogenic anti-Xa assays, especially in case of drug-drug interactions or physiological disorders.

Materials And Methods: We evaluated the contribution of the main metabolite of edoxaban, edoxaban-M4 (M4), in 79 plasma samples from patients taking edoxaban. The total anti-Xa activity was evaluated on three different chromogenic factor Xa-based assays.

Assessment of acquired activated protein C resistance with the FibWave and comparison with the ETP-based APC resistance.

Introduction: Activated protein C (APC) resistance is a major risk factor of venous thrombosis which may be acquired by hormonal therapy or other causes. The FibWave, a sensitive global clot-based assay design to analyze the coagulation kinetics in plasma, may be a good candidate to assess this prothrombotic state. This study aims to assess the suitability of the FibWave to differentiate the coagulation kinetics of women on oral contraceptives.

Comprehensive review of the impact of direct oral anticoagulants on thrombophilia diagnostic tests: Practical recommendations for the laboratory.

There is a laboratory and clinical need to know the impact of direct oral anticoagulants (DOACs) on diagnostic tests to avoid misinterpretation of results. Although the regulatory labelling documents provide some information about the influences of each DOAC on diagnostic tests, these are usually limited to some of the most common tests and no head to head comparison is available. In this paper, we report the impact of DOACs on several thrombophilia tests, including assessment of antithrombin, protein S and protein C activity assays, detection of activated protein C resistance and assays used for lupus anticoagulant.

Assessment of low plasma concentrations of apixaban in the periprocedural setting.

Introduction: Estimation of residual apixaban plasma concentrations may be requested in the management of emergencies. This study aims at assessing the performance of specific anti-Xa assays calibrated with apixaban on real-life samples with low apixaban plasma concentrations (<30 ng/mL) and on-treatment ranges, with and without interference of low-molecular-weight heparin (LMWH).

Methods: The performance of the STA -Liquid Anti-Xa assay (STA LAX) and the low and normal procedures of the Biophen Direct Factor Xa Inhibitors (DiXaI) assay was tested on 134 blood samples, collected from patients on apixaban, wherefrom 74 patients received LMWH after apixaban cessation.

Importance of measuring pharmacologically active metabolites of edoxaban: development and validation of an ultra-high-performance liquid chromatography coupled with a tandem mass spectrometry method.

Although DOACs do not require regular measurements of their blood concentrations, clinical situations may require an assessment of their concentration. Among the factor Xa inhibitors, edoxaban is the only compound for which some metabolites (e.g.

Optimal wavelength for the clot waveform analysis: Determination of the best resolution with minimal interference of the reagents.

Introduction: Clot waveform analysis (CWA), a new methodology to assess coagulation process, can be usefully applied in various clinical settings. However, its clinical use is limited mainly because of the absence of standardization. No consensus exists regarding the wavelengths at which CWA has to be performed what is crucial for the sensitivity of the CWA.

Development of new methodologies for the chromogenic estimation of betrixaban concentrations in plasma.

Introduction: Chromogenic anti-Xa assays are the most appropriate tests to estimate the amount of betrixaban in plasma but the sensitivity of available tests is limited and improvements are needed to encompass the on-therapy range.

Methods: Betrixaban was spiked at concentrations ranging from 0 to 500 ng/mL in plasma from healthy donors. Three commercial tests were used (Biophen DiXaI , STA Liquid Anti-Xa, and HemosIL Liquid Anti-Xa), and adaptation of their sample dilution scheme was performed.

Betrixaban: Impact on Routine and Specific Coagulation Assays-A Practical Laboratory Guide.

Introduction:  Betrixaban is a novel direct oral factor Xa inhibitor approved by the Food and Drug Administration for prophylaxis of venous thromboembolism in adult patients hospitalized for an acute illness at risk for thromboembolic complications. Assessment of the anti-coagulant effect of betrixaban may be useful in some situations. Also, clinicians need to know how routine coagulation assays are influenced.