Thirty-one patients (20 male and 11 female; median age 51 years (16-79)) with high-risk acute myeloblastic leukemia (AML) (20 refractory AML and 11 secondary AML (s-AML) (four to myelodysplastic syndrome, five to chemo/radiotherapy, one to aplastic anemia and one blastic chronic myelogenous leukemia (B-CML)) were treated with CBDCA (300 mg/m2/day x 5 days in continuous i.v. infusion) plus intermediate-dose Ara-C (500 mg/m2/day x 3 days in rapid i.v. infusion). Nine patients (29%) achieved CR (five s-AML (three myelodysplastic syndromes, one CML and one ALL) and four refractory AML) and 11 patients had resistant disease. There were 11 early deaths (35%). Median disease-free survival of the nine responders was 4 months. The main toxicity was hematological, febrile episodes took place in nearly all the patients (96%). The CBDCA plus Ara-C regimen showed an evident antileukemic activity in high-risk leukemia. However, the lack of long-term disease-free survivors shows the need for innovative postremission strategies. The high initial response rate seen in AML secondary to myelodysplastic syndromes (MDS) warrants further investigation of CBDCA in combination regimens for MDS patients.