Ppack trifluoroacetate is a peptide derivative that irreversibly and specifically suppresses thrombin-mediated platelet activation by binding with high affinity to the active site of thrombin (Ki: 0.24 nM). It has been utilized as an anticoagulant (100 μM) and to study thrombin-mediated fibrin deposition, angiogenesis, and proinflammatory processes.