Randomized comparison of four-times-daily versus once-daily intravenous Busulfan in conditioning therapy for hematopoietic cell transplantation

Abstract

Sixty patients were randomized to receive intravenous busulfan (iBU) either as 0.8 mg/kg, over 2 hours 4 times a day (BU4 arm) or 3.2 mg/kg, over 3 hours once a day (BU1 arm) in conditioning therapy for hematopoietic cell transplantation. The complete pharmacokinetic parameters for the first busulfan dose were obtained from all patients and were comparable between the 2 arms: for the BU4 and BU1 groups, elimination half-fife (mean +/- SD) was 2.75 +/- 0.22 versus 2.83 +/- 0.21 hours, estimated daily AUC was 6058.0 +/- 1091.9 versus 6475.5 1099.4 mu M center dot min per day, and clearance was 2.05 +/- 0.36 versus 1.91 +/- 0.31 mL/min/kg, respectively. Times to engraftment after transplantation were similar between the 2 arms. No significant differences were evident in the occurrence of acute graft-versus-host disease (aGVHD) and hepatic veno-occlusion disease (VOD). Moreover, other toxicities observed within 100 days after transplantation were not significantly different between the 2 arms. The cumulative incidence of nonrelapse mortality was 20.8% in BU4 arm and 13.3% in BU1 arm. In conclusion, our randomized study demonstrates that the pharmacokinetic profiles and posttransplant complications are similar for once-daily iBU and traditional 4-times-daily iBU. (c) 2007 American Society for Blood and Marrow Transplantation