Bivalirudin Bivalirudin Bivalirudin (Angiomax or Angiox, manufactured by The Medicines Company) is a direct thrombin inhibitor (DTI). Chemically, it is a synthetic congener of the naturally occurring drug hirudin (found in the saliva of the medicinal leech "Hirudo medicinalis"). Bivalirudin is a DTI that overcomes many limitations seen with indirect thrombin inhibitors, such as heparin. Bivalirudin is a short, synthetic peptide. It is a potent and highly specific inhibitor of thrombin. It inhibits both circulating and clot-bound thrombin, while also inhibiting thrombin-mediated platelet activation and aggregation. Bivalirudin has a quick onset of action and a short half-life. It does not bind
Hirudin of thrombin in normal blood circulation is antithrombin. Similar to antithrombin, the anticoagulant activity of hirudin is based on its ability to inhibit the procoagulant activity of thrombin. Hirudin is the most potent natural inhibitor of thrombin. Unlike antithrombin, hirudin binds to and inhibits only the activated thrombin, with a specific activity on fibrinogen. Therefore, hirudin prevents or dissolves the formation of clots and thrombi (i.e., it has a thrombolytic activity), and has therapeutic value in blood coagulation disorders, in the treatment of skin hematomas and of superficial varicose veins, either as an injectable or a topical application cream. In