Continuous infusion idarubicin and intravenous busulphan as conditioning regimen to autologous stem cell transplantation for patients with acute myeloid leukaemia

Abstract

The current study aimed to evaluate the efficacy and toxicity of a combination of intravenous (iv) busulfan (Bu) and continuous infusion Idarubicin (IDA) as a conditioning regimen to autologous haematopoietic stem cell transplantation (ASCT) in patients with acute myeloid leukaemia (AML). The protocol included IDA at 20 mg/sqm daily as 3 days continuous infusion (from day -13 to -11) and intravenous BU at 3.2 mg/kg daily from day -5 to -2. Patients aged over 60 years received a reduced schedule (2 days IDA and 3 days BU at the same dose). Twenty-five patients with a median age of 51 years (28-72) were enrolled. All patients received peripheral blood stem cells (PBSC). The median interval between diagnosis and ASCT was 4 months. The median number of CD34+ cells infused was 5.9 x 10E6/kg. The median number of days to PMN >500/cmm and platelets >20000/cmm was 10 and 13, respectively. In order to perform a comparison in terms of haematological and non haematological toxicity, a group of 30 patients, who were previously autografted after conditioning with IDA and oral Bu was considered. Selection of factors for a matched pair analysis included median age, percentage of subjects aged over 60 years, median CD34+ cell received, cytogenetic and molecular findings and per cent of secondary AML. As compared to previous series, the occurrence of severe mucositis was dramatically reduced (80% vs. 12%, p < 0.0001). In addition, need and duration of total parenteral nutrition (TPN), iv antibiotic therapy and hospitalization were also significantly reduced. We conclude that replacement of oral with intravenous BU results in a more favourable toxicity profile. A longer follow-up is required to assess a potential advantage in terms of disease free survival (DFS).