Less veno-occlusive disease after intravenous versus oral busulfan for autologous haematopoietic stem cell transp.l antation: the Belgian paediatric experlence

Busulfan is commonly used in preparative conditioning regimens prior to haematopoietic stem cell transplantation in children and young adults for malignant and non-malignant dis- orders. For many years busulfan was only available in oral form, resulting in large inter- and intra-patients variability in plasma exposure, associated with higher graft failure rate as well as higher toxicity such as veno-occlusive disease. With the development of an intravenous formulation of busulfan, a more accurate control of both the inter- and intra-patient variabil- ity has been provided. The goal of this study was to evaluate the use and efficacy of intra - venous busulfan in comparison with the oral formulation in children undergoing an autolo- gous transplantation after conditioning with busulfan. Despite the small number of patients, this study confirmed the apparent benefit of intravenous busulfan in children undergoing an autologous HSCT. The use of a five-level dose schedule defined by body weight resulted in an efficient engraftment with marked reduction in the incidence of veno-occlusive disease compared with oral busulfan. In terms of disease-free outcome, survival and event-free sur- vival, similar results have been obtained in both groups. The choice of this formulation of busulfan should therefore be considered. (Belg J Hematol 2012;3:34-40)