Patients undergoing orthotopic liver transplantation (OLT) have excessive blood loss during surgery that requires blood transfusions, leading to increased postoperative morbidity and mortality. We studied the efficacy and safety of activated recombinant factor VII (rFVIIa) in reducing transfusion requirements in OLT. This multicenter, randomized, double- blind, placebo-controlled trial enrolled patients undergoing OLT because of cirrhosis (Child-Turcotte-Pugh class B or C). Patients received a repeated intravenous bolus regimen of rFVIIa 60 or 120 g/kg or placebo. The primary efficacy endpoint was the total number of red blood cell (RBC) units transfused during the perioperative period. A total of 182 patients were analyzed for efficacy and 183 for safety. No significant effect of rFVIIa was observed on the number of RBC units transfused or intraoperative blood loss compared with the placebo group. A significantly higher number of patients in the rFVIIa study groups avoided RBC transfusion. Administration of rFVIIa but not placebo restored the preoperative prolonged prothrombin time to normal value during surgery. Patients receiving rFVIIa and placebo did not experience a significant difference in rate of thromboembolic events. Additionally, there was no statistically significant effect of rFVIIa treatment on hospitalization rate, total surgery time, and the proportion of patients undergoing retransplantation. In conclusion, use of rFVIIa during OLT significantly reduced the number of patients requiring RBC transfusion. There was no increase in thromboembolic events with rFVIIa administration compared with placebo. (Liver Transpl 2005;11:973-979.)