Inclusion Criteria: - Males or females at least 18 years of age - Patients with relapsed or refractory Acute myelogenous leukemia (AML) or AML secondary to myelodysplastic syndromes, myeloproliferative neoplasm, or chronic myelogenous leukemia - Part B only: AML with no more than two prior salvage regimens - Part B only: Patients positive for a select tumor marker - Eastern Oncology Cooperative Group (ECOG) performance status 0-2 and considered likely to complete at least 4 weeks of therapy Exclusion Criteria: - With the exception of alopecia, any unresolved toxicities from prior therapy greater than CTCAE grade 1 at the time of starting study treatment. - As judged by the investigator, any evidence of severe or uncontrolled systemic diseases, including uncontrolled hypertension, active bleeding diatheses, or active infection including hepatitis B, hepatitis C and HIV. - Active heart disease including myocardial infarction within the last 3 months, symptomatic coronary artery disease, clinically significant arrhythmias not controlled by medication or uncontrolled congestive heart failure - Prior allogeneic transplant requiring immunosuppressive therapy (Patients with prior allogeneic transplants who remain clinically stable for ≥ 2 weeks or more off immunosuppressive therapy, are eligible) - White blood cell count ≥ 100,000/mm3