The most effective regimen for patients with acute myeloid leukemia (AML) who do not achieve complete remission (CR) after one course of cytarabine and an anthracycline has not been extensively studied. We evaluated retrospectively the efficacy, toxicity, and prognostic factors for the achievement of CR following mitoxantrone and etoposide in 74 patients with newly diagnosed AML who did not respond to one course of therapy with cytarabine and idarubicin. CR was achieved in 39% of patients; 14% died of infectious complications; no grade 3 or 4 hepatic toxicities were observed. Median duration of overall survival was 9.0 months (95% CI 5.8-14.9 months). The median duration of relapse-free survival was 11.0 months (95% CI: 9.0-19.3 months). A lower CR rate was associated with unfavorable risk status at diagnosis and higher percent blasts. Our data suggest that the combination of etoposide and mitoxantrone is an effective second-course therapy in patients with newly diagnosed AML.