Assessment of rFVIIa mode of action under FVIII-deficient conditions. rFVIIa was added to FVIII-deficient plasma, and thrombin generation was initiated with 1 pM TF (Innovin, black bars) or direct platelet activators (100 ng/mL convulxin and 30 μM SFLLRN, gray bars). The thrombin peak level is plotted against increasing rFVIIa concentration (0-300 nM). The presence of polyclonal goat-anti-human TF antibodies did not significantly influence the thrombin peak after initiation with the platelet activators (data not shown). Thrombin peak levels are expressed in percentage relative to the thrombin peak in normal human plasma. Data are mean with standard deviation of repeated experiments (n = 3).