Analysis of FIX-WT and FIX variants activities in human HB plasma. (A) Peak thrombin generation as a function of added FIX protein (3.9-250 nM) along with 2 pM TF/4 μM phospholipid into human HB plasma. (B) Peak thrombin generation in the presence of varying concentrations of FVIII (0-8 nM) and FIX-WT or FIX-V16L (125 nM) in the human HB plasma. Peak thrombin is shown on a semilogarithmic plot. Data are representative of 3 independent experiments.