Simple SummaryAzacitidine (AZA) is a hypomethylating agent with well-known antileukemic activity. Due to its favorable safety profile, AZA is widely used alone or in association with other drugs for the frontline treatment of patients with acute myeloid leukemia (AML) unfit for intensive chemotherapy. To date, only a few studies have used AZA as maintenance therapy during complete remission in patients with AML. In our phase-3 randomized multicenter trial, AZA improved disease-free survival (DFS) up to 2 and 5 years in patients aged >68 years compared to best supportive care (BSC). No patients died before leukemic relapse and no differences in patient-reported outcome measures between AZA and BSC patient groups were observed. The most frequent side effect seen in patients was low neutrophil count. In summary, AZA given as a post-remission therapy was found to provide benefit in AML patients aged >68 years.AbstractThis phase-3 randomized multicenter trial evaluated the efficacy of subcutaneous azacitidine (AZA) post-remission therapy vs. best supportive care (BSC) in elderly acute myeloid leukemia (AML) patients. The primary endpoint was the difference in disease-free survival (DFS) from complete remission (CR) to relapse/death. Patients with newly diagnosed AML aged ≥61 years received two courses of induction chemotherapy (“3+7” daunorubicin and cytarabine) followed by consolidation (cytarabine). At CR, 54 patients were randomized (1:1) to receive BSC (N = 27) or AZA (N = 27) at a dose of 50 mg/m2for 7 days every 28 days and the dose increased after the 1st cycle to 75 mg/m2for a further 5 cycles, followed by cycles every 56 days for 4.5 years. At 2 years, median DFS was 6.0 (95% CI: 0.2–11.7) months for patients receiving BSC vs. 10.8 months (95% CI: 1.9–19.6,p= 0.20) months for AZA. At 5 years, DFS was 6.0 (95% CI: 0.2–11.7) months in the BSC arm vs. 10.8 (95% CI: 1.9–19.6,p= 0.23) months in the AZA arm. Significant benefit was afforded by AZA on DFS at 2 and 5 years in patients aged >68 years (HR = 0.34, 95% CI: 0.13–0.90,p= 0.030 and HR = 0.37, 95% CI: 0.15–0.93,p= 0.034, respectively). No deaths occurred prior to leukemic relapse. Neutropenia was the most frequent adverse event. There were no differences in patient-reported outcome measures between study arms. In conclusion, AZA post-remission therapy was found to provide benefit in AML patients aged >68 years.