PRIOR CONCURRENT THERAPY: Biologic therapy: No prior bone marrow and peripheral blood stem cells transplantation No prior anti-CD33 antibody therapy Chemotherapy: Prior cytotoxic chemotherapy for AML allowed No prior chemotherapy for AML in first relapse except hydroxyurea At least 24 hours since prior hydroxyurea Recovered from prior antineoplastic therapy (except alopecia) No concurrent cytotoxic chemotherapy Endocrine therapy: No concurrent immunosuppressive therapy Radiotherapy: Not specified Surgery: Not specified Other: At least 4 weeks since prior investigational agents No other concurrent antileukemic therapy