Twenty-two patients with acute myeloid leukemia (AML), having a median age of 48.3 years (range 26-70; 10 male, 12 female), were treated with 4'-(9-acridinylamino) methanesulphon-m-anisidide (m-AMSA) 100 mg/m2 and cytosine arabinoside (AraC) 2 x 1000 mg/m2i.v. on days 1-5. There were 2M1,8 M2, 9 M4, 2M4 Eo, and 1 M5a. Of these, 12 achieved a complete remission, 3 a partial remission and 6 did not respond. The median remission duration was 9.0 months and the median overall survival 8.1 months. Side-effects of induction consisted mainly of haematological toxicity and infections with a median duration of WHO-grade-4 granulopenia and thrombopenia of 20 and 28 days respectively. Organ toxicity was mild with mucositis and cutaneous and liver toxicity being experienced by only a few patients. There was one treatment-related death. Five-day m-AMSA and intermediate-dose AraC is an easy-to-handle condensed treatment schedule with tolerable toxicity. Its effectiveness in relapsed and refractory AML is comparable to combinations of high-dose AraC with m-AMSA, anthracyclines or etoposide.