CD33KO-HSPC Infusion Followed by CART-33 Infusion(s) for Refractory/Relapsed AML

Phase 1 Study of Lentivirally Transduced T Cells Engineered to Contain Anti-CD33 Linked to TCRζ And 4-1BB Signaling Domains In Combination With CD33KO-HSPC In Subjects With Refractory Or Relapsed Acute Myeloid Leukemia

The purpose of this study is to provide a new type of treatment for AML. This treatment combines a new type of stem cell transplant along with treatment using chimeric antigen receptor (CAR) T cells that have been engineered to recognize and attack your AML cells.

The first treatment is a modified stem cell transplant, using blood-forming stem cells donated from a healthy donor. From the same donor, we will also make CAR T-cells, which are leukemia fighting cells, which will be given to the patient via an infusion into the vein after the transplanted stem cells have started to grow healthy blood cells. The modification of the stem cell transplant means that the healthy bone marrow cells will be "invisible" to the CAR T-cells that are trying to kill the leukemia cells.

Inclusion Criteria:

1. Male or female 18 years of age or older

2. Subjects with AML unlikely to be cured with currently available therapies

   1. AML that has not achieved a complete remission or morphologic leukemia free state by ELN criteria; partial remission or refractory disease (including primary refractory) are eligible; OR:
   2. AML relapsed following allogeneic stem cell transplantation (including MDS evolved to AML post-allogeneic stem cell transplantation). Note: morphologic relapse is not required; persistent/recurrent disease-associated molecular, phenotypic or cytogenetic abnormalities (measurable residual disease, MRD) at any time after allogeneic HCT is eligible; OR:
   3. Subjects with relapsed disease after prior transplant must be off systemic immunosuppression for at least 1 month at the time of enrollment.

3. Subjects must have a suitable stem cell donor.

4. Satisfactory organ function

   1. Creatinine clearance > 40 ml/min
   2. ALT/AST must be ≤ 5x upper limit of normal unless related to disease and < 20 x upper limit of normal if related to disease
   3. Direct bilirubin < 2.0 mg/dl, unless subject has Gilbert's syndrome (≤ 3.0 mg/dL)

5. Left ventricular ejection fraction ≥ 40% as confirmed by echocardiogram or MUGA

6. DLCO > 45% predicted

7. ECOG performance status 0-1

8. Written informed consent is given

9. Subjects of reproductive potential must agree to use acceptable birth control methods

Exclusion Criteria:

1. Pregnant or lactating (nursing) women
2. Active hepatitis B or hepatitis C or HIV infection
3. Concurrent use of systemic steroids or immunosuppressant medications
4. Any uncontrolled active medical disorder that would preclude participation as outlined
5. Subjects with signs or symptoms indicative of CNS involvement.
6. Known history of allergy or hypersensitivity to study product excipients (human serum albumin, DMSO, and Dextran 40)
7. Class III/IV cardiovascular disability according to New York Heart Association Classification
8. Subjects with clinically apparent arrhythmia, or arrhythmias that are not stable on medical management, within 2 weeks of the screening/enrollment visit.