Fourteen adult patients in first complete remission of acute leukemia (A.L.) [6 with acute lymphoblastic leukemia (ALL), 8 with acute non lymphoblastic leukemia (ANLL)] were consolidated with high dose cyclophosphamide and total body irradiation followed by autologous bone marrow transplantation (ABMT) with marrow cleansed in vitro by Asta Z 7557. According to our previously described protocol showing evidence for a wide range of sensitivity from patient to patient, the marrow of each individual patient was incubated with the highest tolerable dose of Asta Z 7557. This dose, individually determined, was defined as the dose sparing between 0 and 10% of CFU-GM (CFU-GM DL95). ABMT was not followed by maintenance therapy. Hematological reconstitution was significantly faster in ALL patients when compared to ANLL patients. Out of these 14 patients: 2 relapsed on months 5 and 15 respectively after ABMT, and 2 died in complete remission on months 3 and 16 respectively, of veno-occlusive disease and encephalitis. Ten patients (70%) remain in complete remission up to a median of 15 months +, with 4 patients over 24 months +.