The purpose of this trial is to identify a dose or doses of INS50589 intravenous infusion that are well-tolerated and which reduce postoperative bleeding and blood product transfusion.

Inclusion Criteria:

• Are scheduled for primary CABG by median sternotomy involving cardiopulmonary bypass
• Willing to receive allogeneic blood product transfusions during and after surgery

Exclusion Criteria:

• Have had previous cardiac surgery
• Have had previous median sternotomy
• Have tendency for bleeding or family history of bleeding
• Have an abnormally low platelet count
• Have received certain anticoagulant or antiplatelet medications within a specified time period prior to the scheduled CABG surgery