Bivalirudin TFA is a synthetic 20 residue peptide which reversibly inhibits thrombin. IC50 Value: Target: thrombin in vitro: Eptifibatide (8 mg/mL) added together with a low (70 ng/mL) concentration of bivalirudin (a direct thrombin inhibitor) effectively (approximately 90%) reduced platelet aggregation induced by thrombin (0.2 U/mL) . In thrombin generation assay (TGA), bivalirudin had no effect on these parameters up to 10 μmol/l . Bivalirudin-facilitated binding of MPO to BAEC resulted also in functional changes in terms of increased NO consumption as well as enhanced MPO-mediated redox modifications. The use of bivalirudinprevented further increase in antiheparin/PF4 antibody IgG levels in rats. Three animals in the 500-mg/kg/24 h group, and 7 animals in the 2000-mg/kg/24 h group in the toxicokinetic assessment phase of the study were found dead or euthanized in extremis (following blood sampling). Plasma concentrations of bivalirudin appeared to be linear and dose independent. Clinical trial: Antithrombotic Effects of Ticagrelor Versus Clopidogrel.