Allogeneic or Haploidentical Stem Cell Transplant Followed By High-Dose Cyclophosphamide in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia

Inclusion Criteria:

- AML without complete remission (CR/CRc/CRi) after at least 2 induction therapies OR

- AML that has relapsed within 6 months after obtaining a CR OR

- AML that has relapsed more than 6 months after obtaining a CR, and has treatment
failure (TF) or progressive disease (PD) following at least 1 re-induction regimen OR

- AML that has relapsed post Allogeneic transplantation

- Active AML (bone marrow blasts ≥ 5% by morphology, staining, or flow) and/or presence
of estramedullary disease

- Available HLA-haploidentical donor that meets the following criteria:

- Blood-related family member (sibling (full or half), offspring, or parent,
cousin, niece or nephew, aunt or uncle, or grandparent)

- At least 18 years of age

- HLA-haploidentical donor/recipient match by at least low-resolution typing per
institutional standards

- In the investigator's opinion, is in general good health, and medically able to
tolerate leukapheresis required for harvesting HSC

- No active hepatitis

- Negative for HTLV and HIV

- Not pregnant

NOTE: there were HLA-matched sibling and HLA-matched unrelated donor cohorts, but those
closed without completion of accrual with Amendment 11

- Karnofsky performance status ≥ 50 %

- Adequate organ function as defined below:

- Total bilirubin ≤ 2.5 mg/dl (unless the patient has a history of Gilbert's
syndrome)

- AST(SGOT) and ALT(SGPT) ≤ 3.0 x IULN

- Creatinine ≤ 2.0 x IULN OR estimated creatinine clearance ≥ 30 mL/min/1.73 m2 by
Cockcroft-Gault Formula

- Oxygen saturation ≥ 90% on room air

- LVEF ≥ 40%

- FEV1 and FVC ≥ 40% predicted, DLCOc ≥ 40% predicted. If DLCO is < 40%, patients
will still be considered eligible if deemed safe after a pulmonary evaluation.

- At least 18 years of age at the time of study registration

- Able to understand and willing to sign an IRB approved written informed consent
document (or that of legally authorized representative, if applicable)

Exclusion Criteria:

- Circulating blast count ≥ 10,000/uL by morphology or flow cytometry (cytoreductive
therapies including leukapheresis or hydroxyurea are allowed)

- Known HIV or Active hepatitis B or C infection

- Known hypersensitivity to one or more of the study agents

- Currently receiving or has received any investigational drugs within the 14 days prior
to the first dose of study drug (Day -7)

- Currently receiving or has received any intensive chemotherapy within the 14 days
prior to the first dose of study drug (Day -7) (hydrea or other non-intensive regimens
such as decitabine may be used but must stop at least one day prior to the first dose
of study drug)

- Pregnant and/or breastfeeding

- Uncontrolled intercurrent illness including, but not limited to, ongoing or active
infection, symptomatic congestive heart failure, unstable angina pectoris, unstable
cardiac arrhythmias, or psychiatric illness/social situations that would limit
compliance with study requirements.