Version Testing of EnzySystem Version A for Hemophilia A

Standard blood draw by venipuncture is performed in all study participants to collect blood samples in four 2.7 mL citrated blood tubes. Tube one is a dummy tube and is discarded. Tube two is used for the FVIII activity and thrombin generation assay on the EnzySystem. Tube three is used to perform conventional FVIII activity and thrombin generation assays. Tube four is used for duplicate measurements of the conventional assays and measurement of prothrombin F1+2 antigen levels, ADAMTS13 activity, FVIII antigen, VWF (von Willebrand Factor) antigen and von Willebrand ristocetin cofactor activity levels.