Eligible subjects must meet all of the following criteria:
1. Subject must have confirmation of diagnosis of AML (except for acute promyelocytic leukemia \[APL\]) or MDS per 2016 World Health Organization (WHO) criteria.
2. For AML (except for APL) cohort:
1. Previously treated relapsed/refractory AML subjects
3. For MDS cohort: Adult TN MDS and R/R MDS: revised International Prognostic Scoring System (IPSS-R) score \> 3 and bone marrow blasts ≥ 5%.
4. Subject must have a projected life expectancy of at least 12 weeks.
5. Subject must have adequate renal function as demonstrated by a creatinine clearance ≥ 30 mL/min; determined via urine collection for 24-hour creatinine clearance or by the Cockcroft-Gault formula.
6. Subject must have adequate liver function
You may not be if
1. R/R AML or R/R MDS with no response or intolerance to post azacitidine or BCL-2i.
2. Subject has acute promyelocytic leukemia (French-American-British Class M3 AML) .
3. Subject has known central nervous system (CNS) leukemia.
4. Suggest patients with active hepatitis B or C virus infection
5. History of immunodeficiency, including a positive human immunodeficiency virus (HIV) antibody test.
6. Subjects have another active malignancy within the past 2 years before study entry, except for curatively treated.
