Hirudin

Belongs to the class of bivalent direct thrombin inhibitors, which also include Bivalirudin, Lepirudin, and Desirudin. Called bivalent because they bind both the active site and an allosteric site on the thrombin molecule to prevent coagulation. Mainly used to treat Heparin-Induced Thrombocytopenia. The drug is cleared by the kidney.