Inclusion Criteria:

1. Untreated acute myelogenous leukemia (AML), including patients with an antecedent
hematologic disorder or secondary disease. Patients with prior myelodysplastic
syndromes (MDS) may have received therapy with immunomodulatory agents or
hypomethylating agents for this diagnosis. patients with other prior cancer diagnoses
are allowed as long as they ahve no measurable disease are not undergoing active
therapy, and have a life expectancy of greater than or equal 4 months.

2. Patients age greater than or equal to 60 years who: a. Are unwilling to receive
intensive (e.g. 7+3) chemotherapy, or b. Have poor-risk prognostic factors defined as
antecedent hematologic disorder, prior chemotherapy or chemoradiation therapy (XRT),
abnormal karyotype other than t(8;21), inv16, or t(16;16), any karyotype with
Internal tandem duplications of Flt3 (Flt3-ITD), or presenting white blood count
(WBC) greater than 100K, or c. Have significant comorbidities, that in the judgment
of the investigator makes the subject unsuitable for standard dose induction
chemotherapy (e.g. anthracycline and infusional cytarabine given as 7+3); or d. Any
patient age greater than or equal to 70 years.

3. Blast count greater than or equal to 20 percent (World Health Organization (WHO)
criteria)

4. Greater than 25 percent of blasts must be CD33 positive.

5. Creatinine less than 2.0 mg/dl

6. Estimated creatinine clearance greater than or equal to 50ml/min.

7. Bilirubin less than or equal to 2.0 mg/dl; aspartate aminotransferase (AST or SGOT)
and alanine aminotransferase (ALT or SGPT) less than or equal to 2.5 times the upper
limits of normal (ULN).

8. Eastern Cooperative Oncology Group (ECOG) Performance status less than or equal to 3.

Exclusion Criteria:

1. Patients with acute promyelocytic leukemia.

2. Treatment with chemotherapy or biologic therapy within 3 weeks, except for
hydroxyurea, which must be discontinued prior to treatment on study

3. Treatment with radiation within 6 weeks

4. Active serious infections uncontrolled by antibiotics

5. Active malignancy within 2 years of entry, except previously treated non-melanoma
skin cancer, carcinoma in situ or cervical intraepithelial neoplasia, and organ
confined prostate cancer with no evidence of progressive disease based on
prostate-specific antigen (PSA) levels and are not on active therapy

6. Clinically significant cardiac or pulmonary disease

7. Active central nervous system (CNS) leukemia. Patients with symptoms of CNS
involvement, particularly those with M4 or M5 subtypes, should undergo lumbar
puncture prior to treatment on study to exclude CNS disease. Symptoms include cranial
neuropathies, other neurologic deficits, and headache.

8. Psychiatric disorder that would preclude study participation