De effecten van Cofact op Rivaroxaban plasma in trombine generatie assays

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1 De effecten van Cofact op Rivaroxaban plasma in trombine generatie assays In vitro assessment, using thrombin generation, of the applicability of Prothrombin Complex Concentrate as an antidote for Rivaroxaban Jasper Dinkelaar

2 New Oral AntiCoagulants Indirect OAC s AT mediated Proteine C mediated Direct OAC s Directly target a specific coagulation enzyme OLVG Rivaroxaban: a direct Xa inhibitor Dabigatran: a direct IIa inhibitor Michael P. Gulseth et al. Am J Health-Syst Pharm

3 Rivaroxaban Direct Xa inhibitor Max concentration 2-4h Half-life 7-11h 2/3 metabolized in liver,1/3 eliminated unchanged 2/3 renal excretion, 1/3 fecal excretion As or more effective anticoagulant treatment Less (severe) bleeding complications vs VKA Predictable pharmacokinetics Broad therapeutic window No need for assessment No need for reversal therapy Bauer KA. J Thromb Haemost 2011;9(Suppl 1):12 9. EMA Xarelto product information

4 Assessment of NOAC s Monitoring of compliance after therapy failure Assessment of haemostatic balance at acute interventions Bleeding complications Renal failure Over dosage Unknown patients in emergency setting Standard test as PT/INR and aptt are not applicable 1 Several commercial axa have been developed 2 Thrombin generation assays 1 1 Molenaar PJ. et al. Clin Chem Lab Med 2012;50(10): , 2 Hillarp A. et el. J Thromb Haemost 2011 Jan;9(1):133-9, Samama MM et al. Thromb Haemost 2010 Apr;103(4):

5 Reversal of Rivaroxaban Is PCC (Cofact) able to reverse Rivaroxaban anticoagulation. Can we monitor this effect with PT and Thrombin generation

6 Study Design Plasma & Whole blood samples: Spiked with Rivaroxaban, up to 800 ug/l Stroke prevention: 20 mg daily -> 222 ug/l peak 3h 1 Spiked with PCC up to 2-4 IU/ml plasma Approximately 1 IU/ml to normalize an INR of Plasma: Prothrombin Time (PT) Endogenous thrombin potential (EPT) Calibrated automated thrombography (CAT) Whole blood: Calibrated automated thrombography (CAT) 1 W. Mueck et al. Thromb Haemost (3), Sanquin product information

7 Thrombin Generation ETP Chromogenic Assay Platelet poor plasma High Tissue Factor concentration (346 pm) Fibrin aggregation inhibited CAT Fluorogenic Assay PPP / whole blood Low Tissue Factor concentration ( pm) Fibrin aggregation allowed

8 Devreese et al. Thromb Haemost 2007; 98: thrombin generation

9 PT Good responds to rivaroxaban addition Large inter individual variation PCC addition has little effect on PT prolongation

10 ETP Individuele donoren n = pm TF D,E,F 200( ) and 800 ( ) µg/l Rivaroxaban

11 CAT Poolplasma, n = 3 = 1 pm = 5 pm = 20 pm TF

12 Tissue Factor ETP method (standard) 300 pm TF ( ) CAT method with 20 pm TF ( ) 5 pm TF ( ) 1 pm TF ( ) Influence of TF concentration on AUC outcome Rivaroxaban anticoagulated plasma

13 Whole blood & PPP Volbloed n = 3, PPP n = 6 Concentraties Rivaroxaban en PCC in volbloed 50% = volbloed, = plasma

14 Rivaroxaban neutralization PCC concentration required to normalize Thrombin Generation parameters in Rivaroxaban anticoagulated plasma (200 µg/l) and whole blood (100 µg/l) Lag time can not be reversed Response of AUC on Rivaroxaban reversal with PCC is TF dependant Response of AUC has a high inter individual variation

15 Conclusion PCC does not reverse PT or Lag Time These assay s are not suitable to monitor reversal therapy AUC (ETP and CAT) can be normalized by PCC These assay s can be used to monitor reversal therapy Response on Rivaroxaban and subsequent reversal with PCC is assay and TF dependant It remains unclear which assay describes in vivo haemostasis best whether delaying effect of Rivaroxaban on PT and lag time is associated with bleeding complications if AUC normalization by PCC indeed is associated with reversal of Rivaroxaban anticoagulation

16 Acknowledgements Hematologisch Klinisch chemisch laboratorium OLVG Pascal Molenaar Herm-Jan Brinkman Marisa Ninivaggi Bas de Laat Anja Leyte Sanquin Bayer