This is a single arm, open-label, Phase II study of CLOFARABINE in adult patients with refractory or relapsed acute myelogenous leukemia (AML). Qualified patients must be refractory to one or two induction regimens, or have relapsed < one year from the date of confirmation of the initial complete remission (CR). There will be two phases in this study - an Induction phase and a Consolidation phase.