Study of Clofarabine & Cytosine Arabinoside Therapy for Older Adults With Acute Myeloid Leukemia

Inclusion Criteria:

* Have newly diagnosed AML (FAB classification types M0-M2 or M4-M7 or WHO classification) excluding acute promyelocytic leukemia (APL) or AML with any of the following chromosomal translocations: t(15;17)(q22;q21); t(11;17)(q23;q21); t(11;17)(q13;q21); t(5;17)(q32;q12)..
* Have greater than or equal to 20% blasts in the bone marrow.
* Have greater than or equal to 20% cellularity in the bone marrow.
* Provide written informed consent.
* Must be 60-75 years of age at diagnosis.
* Have an Karnofsky performance status of ≥60.
* Women of childbearing potential (\<1 year post-menopausal unless surgically sterilized) and sexually active males must have a negative urine pregnancy test, and agree to use an effective barrier method of birth control (i.e. latex condom, diaphragm, cervical cap, etc) to avoid pregnancy.
* Able to comply with study procedures and follow-up examinations.
* Have adequate organ function as indicated by the following laboratory values, obtained within 7 days prior to registration:

Parameter Required Value (IS units) Renal Serum creatinine \<1.1 mg/dL Hepatic Serum bilirubin \<2 x ULN AST and ALT ≤5 x ULN ULN = Institutional Upper Limit of Normal. Inclusion Laboratory Values

Exclusion Criteria:

* Patients with pre-existing myelodysplastic syndrome, or with antecedent hematologic disorder of \>3 months duration, will be excluded. Those with concomitant myelodysplasia/trilineage dysplasia noted at the time of diagnosis of AML will be eligible 74
* Have secondary AML (AML following chemotherapy or radiation therapy).
* Have an active, uncontrolled systemic infection considered opportunistic, life threatening, or clinically significant at the time of treatment.
* Have a psychiatric disorder(s) that would interfere with consent, study participation or follow-up.
* Are receiving other chemotherapy or corticosteroids (unless the latter is administered at a low dose for pre-medication purposes or for the treatment of chronic conditions - e.g., rheumatoid arthritis).
* Have received prior treatment for leukemia. Patients who have received growth factors, cytokine support, leukapheresis, hydroxyurea, or cranial irradiation will be allowed but must discontinue treatment at least 24 hours prior to beginning treatment with clofarabine. If used, hydroxyurea must be discontinued 48 hours prior to the initiation of chemotherapy.
* Have any other severe concurrent disease (severe coronary artery disease (NYHA class \>II), significant neurological disorder, uncontrolled diabetes, etc.), which, in the judgment of the investigator, would make the patient inappropriate for entry into this study.
* Have active central nervous system involvement with leukemia.
* Other malignancy within the past year, with the exception of basal cell or non-metastatic squamous cell carcinoma of the skin