Pexelizumab in Patients Undergoing Coronary Artery Bypass Grafting With Cardiopulmonary Bypass (PRIMO-CABG II)

During a heart bypass procedure, a substance called "complement" is activated by the body. This "complement activation" causes an inflammatory response that can lead to side affects such as chest pain, heart attacks, stroke, heart failure, or death. The purpose of this study is to find out if the study drug (pexelizumab), that blocks "complement activation," can reduce such side effects and be given safely to patients requiring the bypass procedure with the use of the heart-lung machine.