Decitabine (Dacogen^®) is a deoxynucleoside analogue of cytidine that selectively inhibits DNA methyltransferases. Decitabine administered at a dose of 20 mg/m² by a 1-h intravenous infusion for 5 consecutive days of a 4-week cycle has been approved by the European Medicines Agency (EMA) for use in adult patients aged ≥65 years with de novo or secondary acute myeloid leukaemia (AML) who are not candidates for standard induction therapy. Decitabine, compared with treatment choice (cytarabine or supportive care), did not result in a statistically significant improvement in median overall survival (OS) in older patients with AML at the pre-specified primary endpoint of a pivotal phase III trial. However, the improvement in OS was considered by the EMA to be clinically meaningful. After a further year of follow-up, an analysis of the mature survival data demonstrated a statistical significance in median OS in favour of decitabine over treatment choice. Complete remission (CR) rates in the phase III trial were significantly improved with decitabine versus treatment choice. The overall safety profile of decitabine in older patients with AML was generally similar to that of cytarabine, with pyrexia, thrombocytopenia and anaemia being the most commonly reported adverse events. In conclusion, low-dose decitabine may be considered as an effective and generally well tolerated alternative treatment to cytarabine or supportive care in older patients with AML who are not candidates for standard induction therapy.