Twenty adult patients with high-risk leukaemia underwent allogeneic haemopoietic stem cell transplantation after melphalan, busulphan and total body irradiation followed by short-term methotrexate and low-dose cyclosporine or tacrolimus. Three patients developed veno-occlusive disease and no patient developed renal dysfunction. Seven patients experienced grade II-IV acute graft-versus-host disease (aGVHD) and five patients experienced grade III-IV. The 3-year probabilities of relapse and leukaemia-free survival were 22 +/- 11% (95% confidence interval) and 50 +/- 11%, respectively. These data suggest that this preconditioning regimen followed by a low-dose immunosuppressant provided a more anti-leukaemic effect without increased regimen-related toxicity and aGVHD.