Inclusion Criteria:

          -  Patients with relapsed or refractory AML

          -  Newly diagnosed elderly AML patients (> 60 years) unfit for intensive chemotherapy
             with cytarabine and anthracyclines are also eligible to this trial given that no
             clinically beneficial therapy exists for these patients

          -  Patients with secondary AML or therapy related disease (t-AML) are eligible; patients
             who received decitabine or 5-azacytidine as prior treatment for myelodysplastic
             syndrome (MDS) or AML remain eligible; however, none of these agents is permitted
             within 6 months of study entry

          -  If the patient has co-morbid medical illness, life expectancy attributed to this must
             be greater than 6 months

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

          -  Total bilirubin < 2.0 mg/dL

          -  Aspartate aminotransferase (AST) (serum glutamic oxaloacetic transaminase
             [SGOT])/alanine aminotransferase (ALT) (serum glutamate pyruvate transaminase [SGPT])
             < 2.5 X institutional upper limit of normal

          -  Creatinine < 2.0 mg/d

          -  Glomerular filtration rate (GFR) > 50 mL/min

          -  New York Heart Association (NYHA) congestive heart failure (CHF) class II or better

          -  Female patients of child-bearing potential must agree to use dual methods of
             contraception and have a negative serum pregnancy test at screening, and male patients
             must use an effective barrier method of contraception if sexually active with a female
             of child]bearing potential; acceptable methods of contraception are condoms with
             contraceptive foam, oral, implantable or injectable contraceptives, contraceptive
             patch, intrauterine device, diaphragm with spermicidal gel, or a sexual partner who is
             surgically sterilized or post-menopausal; for both male and female patients, effective
             methods of contraception must be used throughout the study and for three months
             following the last dose

          -  Ability to understand and willingness to sign the written informed consent document

          -  Human immunodeficiency virus (HIV) infection without history of acquired immune
             deficiency syndrome (AIDS) and sufficiently high cluster of differentiation (CD)4
             cells (> 400/mm^3) and low HIV viral loads (< 30,000 copies/ml plasma) not requiring
             anti-HIV therapy are eligible

          -  Patients must have recovered from the toxicity of prior therapy to less than grade 2

        Exclusion Criteria:

          -  Patients who have had chemotherapy or radiotherapy within 2 weeks (6 weeks for
             nitrosoureas or mitomycin C) prior to entering the study

          -  Patients receiving any other investigational agents or patients that have received
             other investigational agents within 14 days of enrollment

          -  Patients with active central nervous system (CNS) malignancy; asymptomatic small
             lesions are not considered active; treated lesions may be considered inactive if they
             are stable for at least 3 months; patients with malignant cells in their cerebrospinal
             fluid (CSF) without CNS symptoms may be included

          -  Patients with history of allergic reactions attributed to compounds of similar
             chemical or biologic composition to decitabine that are not easily managed

          -  Major surgery within 2 weeks before day 1

          -  Uncontrolled active infection requiring parenteral antibiotics, antivirals, or
             antifungals within one week prior to first dose

          -  Known active hepatitis A, B, or C infection; or known to be positive for hepatitis C
             virus (HCV) ribonucleic acid (RNA) or HBsAg (hepatitis B virus [HBV] surface antigen)

          -  Patients with significantly diseased or obstructed gastrointestinal tract or
             uncontrolled vomiting or diarrhea

          -  History of seizures, movement disorders or cerebrovascular accident within the past 3
             years prior to cycle 1 day 1

          -  Patients with macular degeneration, uncontrolled glaucoma, or markedly decreased
             visual acuity

          -  Uncontrolled intercurrent illness including, but not limited to, symptomatic
             congestive heart failure (New York Heart Association [NYHA] class III or IV), unstable
             angina pectoris, myocardial infarction within 6 months prior to enrollment, severe
             uncontrolled ventricular arrhythmias, or electrocardiographic evidence of acute
             ischemia or active conduction system abnormalities; prior to study entry, any
             electrocardiogram (ECG) abnormality at screening has to be documented by the
             investigator as not medically relevant

          -  Patients with serious medical or psychiatric illness likely to interfere with
             participation in this clinical study

          -  Pregnant women or women who are breastfeeding are excluded from this study;
             confirmation that the subject is not pregnant must be established by a negative serum
             beta-human chorionic gonadotropin (beta-hCG) pregnancy test result obtained during
             screening; pregnancy testing is not required for post-menopausal or surgically
             sterilized women

          -  Patients with advanced malignant solid tumors are excluded

          -  Patients with renal failure (GFR < 50 mL/min) are excluded

          -  Patients that in the opinion of the investigators are significantly below their ideal
             body weight