Efficacy Study of Recombinant Protein (Ecallantide) to Reduce Blood Loss During Primary Coronary Bypass Grafting or Valve Repair/Replacement

This was a Phase 2, randomized, double-blind, placebo-controlled, multi-center study designed to assess the efficacy and safety of 2 dose levels of ecallantide compared to placebo in reducing chest tube drainage in participants requiring CPB for primary CABG, single valve repair, or single valve replacement. Participants were randomized in a 3:3:2 ratio to ecallantide high-dose regimen (maximum 91 mg), ecallantide low-dose regimen (maximum 15 mg), or placebo. Randomization was stratified by surgical procedure so that participants undergoing valve replacement would be evenly distributed across treatment arms. Each participant received active drug or placebo administered in stages on the day of the surgical procedure after induction of anesthesia (Day 1). Participants were screened up to 14 days prior to surgery. Additional study procedures were conducted on Day -1 or 1, peri-operatively, during the immediate postoperative period, and on Days 2, 4, and 7 (or at the time of discharge from the hospital), and between Days 28 and 43 (follow-up).