Inclusion Criteria:

- Diagnosis of AML (de novo, secondary or with an antecedent hematologic disorder
[AHD])

- Age ≥ 60 years

- Eastern Cooperative Oncology Group (ECOG) performance status 0-2

- Presence of at least one adverse prognostic factor: Age ≥ 70 years; or AHD; or ECOG
performance status of 2; or Intermediate or unfavorable (i.e., adverse) karyotype
defined as any cytogenetic profile except the presence of any of the following:

- t(8;21)(q22;q22)

- inv(16)(p13;q22 or t(16;16)(p13;q22)

- t(15;17)(q22;q12) and variants.

- Adequate renal and hepatic function: Total bilirubin ≤ 1.5 x upper limit of normal
(ULN); Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 x
ULN; and Serum creatinine ≤ 1.0 mg/dL; if serum creatinine > 1.0 mg/dL, then the
estimated glomerular filtration rate (GFR) must be > 60 mL/min/1.73 m^2 as calculated
by the Modification of Diet in Renal Disease (MDRD) equation

- Adequate cardiac function: left ventricular ejection fraction (LVEF) ≥ 40% or left
ventricular fractional shortening ≥ 22%

Exclusion Criteria:

- Diagnosis of acute promyelocytic leukemia

- Prior treatment with clofarabine

- Prior treatment for AML or an antecedent hematologic disorder

- Prior hematopoietic stem cell transplant (HSCT)

- Prior radiation therapy to the pelvis

- Investigational agent received within 30 days prior to the first dose of study drug

- Ongoing uncontrolled systemic infection

- Diagnosis of another malignancy, unless the patient has been disease-free for at
least 5 years following the completion of curative intent therapy with the following
exceptions: Patients with treated non-melanoma skin cancer, in-situ carcinoma or
cervical intraepithelial neoplasia regardless of disease-free duration are eligible
for this study if definitive treatment for the condition has been completed; Patients
with organ-confined prostate cancer with no evidence of recurrent or progressive
disease based on PSA value are eligible for this study if hormonal therapy has been
initiated or a radical prostatectomy has been performed

- Clinical evidence of central nervous system (CNS) involvement

- Severe concurrent medical condition or psychiatric disorder that would preclude study
participation

- Positive human immunodeficiency virus (HIV) test