Combination of Quizartinib and Omacetaxine Mepesuccinate for AML Carrying FLT3-ITD

Inclusion Criteria: 1. Provision of written informed consent approved by the Institutional Review Board (IRB). 2. Age ≥18 years 3. Documented primary AML or AML secondary to myelodysplastic syndrome (MDS), as defined by World Health Organization criteria 4. At diagnosis or in morphological relapse after an initial remission or refractory after induction chemotherapy, with or without HSCT 5. Documentation of FLT3-ITD in BM or blood with allelic burden of ≥ 20% as determined by the study site laboratory 6. ECOG performance score 0-2 7. Discontinuation of prior AML treatment ≥ 2 weeks before the start of QUIZOM (except hydroxyurea or other treatment to control leukocytosis). 8. Serum creatinine ≤1.5×upper limit of normal (ULN), or glomerular filtration rate \>25 mL/min, as calculated with the Cockcroft-Gault formula. 9. Serum potassium, magnesium, and calcium (corrected for albumin) within institutional normal limits. Subjects with electrolytes outside the normal range will be eligible if these values are corrected upon retesting following any necessary supplementation. 10. Total serum bilirubin ≤1.5×ULN. 11. Serum aspartate transaminase (AST) and/or alanine transaminase (ALT) ≤ 2.5×ULN. Exclusion Criteria: 1. Acute promyelocytic leukemia (AML subtype M3) 2. Prior treatment with any FLT3 inhibitors 3. Known infection with human immunodeficiency virus, or active hepatitis B or C infection. 4. Refusal of blood product transfusion. 5. Uncontrolled or significant cardiovascular disease, including: i. QTcF interval \> 450 msec ii. Bradycardia of ≤ 50 BPM iii. Diagnosed or suspected long QT syndrome, or known family history of long QT syndrome iv. History of clinically relevant ventricular arrhythmias, such as ventricular tachycardia, ventricular fibrillation, or torsade de pointes v. History of second or third degree heart block. Candidates with a history of heart block may be eligible if they currently have pacemakers, and have no history of fainting or clinically relevant arrhythmia with pacemakers. vi. Myocardial infarction within 6 months prior to screening vii. Uncontrolled angina pectoris within 6 months prior to screening viii. New York Heart Association (NYHA) Class 3 or 4 congestive heart failure ix. Uncontrolled hypertension x. Complete left or right bundle branch block 6. In a man whose sexual partner is a woman of childbearing potential, unwillingness or inability of the man or woman to use an acceptable contraceptive method for the entire study treatment period and for at least 3 months after study treatment completion 7. In a heterosexually active woman of childbearing potential, unwillingness or inability to use an acceptable contraceptive method for the entire study treatment period and for at least 3 months after study treatment completion 8. Pregnancy 9. Female subjects must agree not to breastfeed at screening and throughout the study period, and for 45 days after the final study drug administration.