A Dose-ranging Safety and Efficacy Study of Ecallantide to Reduce Surgical Blood Loss Volume

Inclusion Criteria: * Written informed consent (by study subject or appropriate legal representative) prior to any study-related procedure not part of normal medical care * Planned primary CABG surgery including the use of cardio-pulmonary bypass. Exclusion Criteria: * Planned concomitant surgery including ASD repair, valve replacement, carotid endarterectomy, CABG combined procedures or any repeat sternotomy; * Body weight \<55 kg; * Planned hypothermia (\<28ºC); * Planned transfusion in the peri-operative or post-operative periods; * Planned transfusion of pre-operatively donated autologous blood; * Female subjects who are pregnant or lactating; * Planned use of desmopressin, lysine analogs, atrial natriuretic hormone or recombinant activated Factor VII; * Planned use of corticosteroids in the pump prime solution; * Ejection fraction \<30% within 90 days prior to surgery; * Evidence of a myocardial infarction within 5 days prior to surgery; * History of stroke or transient ischemic attack within 3 months prior to surgery; * Hypotension or heart failure requiring the use of inotropes or mechanical devices within 24 hours prior to surgery; * Serum creatinine \>2.0 mg/dL within 48 hours prior to surgery; * Serum hepatic enzymes above 2.5 times the upper limit of normal for the applicable laboratory; * Hematocrit \<32% within 48 hours prior to surgery; * Platelet count below the normal range for the applicable laboratory within 14 days prior to surgery; * History of, or family history of, bleeding or clotting disorder or thrombophilia; * History of heparin-induced thrombocytopenia; * Prothrombin time and/or activated partial thromboplastin time \>1.5 X normal range; * Serious intercurrent illness or active infection; * Any previous exposure to ecallantide; * Receipt of an investigational drug or device 30 days prior to participation in the current study; * Known allergy to any agent expected to be used in the intra-operative or post-operative periods; and * Administration of: Eptifibatide within 6 hours prior to surgery, Tirofiban HCl within 6 hours prior to surgery, \*Enoxaparin sodium or other low-molecular-weight heparin \<24 hours prior to surgery, Clopidogrel within 5 days prior to surgery, Ticlopidine within 7 days prior to surgery, Abciximab within 5 days prior to surgery, \*Bivalirudin, argatroban or lepirudin within 6 hours prior to surgery, \*Fondaparinux within 72 hours prior to surgery, Prasugrel within 10 days prior to surgery \[\*Prophylactic use permitted for the prevention of deep vein thrombosis.\]