The Eastern Cooperative Oncology Group (ECOG) conducted a prospective phase III study in patients with relapsed/refractory acute myeloid leukemia (AML) to evaluate whether administration of repeated courses of low-dose cytarabine (LDAC) maintenance therapy after induction of complete remission in advanced AML would improve disease-free and overall survival. Patients with AML in second/later relapse or refractory disease were first treated with a combination of high-dose cytarabine and amsacrine. Those who achieved complete remission were then randomized to observation or to receive LDAC, 10 mg/m2 subcutaneously twice a day x2 21 days every 2 months until relapse occurred. Of 86 patients eligible for randomization, 41 patients were assigned to receive LDAC and 45 patients to observation. The median disease-free survival was 7.4 months for patients assigned to LDAC compared to 3.3 months for patients receiving no additional therapy, P= 0.084. The median survival from randomization was 10.9 months and 7.0 months for patients receiving LDAC maintenance chemotherapy and observation, respectively (P= 0.615). The data from this study suggest that LDAC maintenance therapy given to patients with advanced AML who achieve complete remission can increase disease-free survival compared to observation, but does not improve overall survival. Nevertheless, because of the ineffectiveness and toxicity of intensive post-remission chemotherapy in this circumstance, LDAC maintenance therapy, a tolerable outpatient regimen, offers the potential for improved quality of life.