Eltanexor and Venetoclax in Relapsed or Refractory Myelodysplastic Syndrome and Acute Myeloid Leukemia

Primary objective: • To establish the safe and biologically effective dose (BED) of eltanexor in combination with venetoclax in patients with R/R MDS and/or AML Secondary objectives: * To estimate the complete remission (CR) rate with eltanexor and venetoclax in patients with R/R MDS and/or AML * To assess the overall response rate (ORR) following treatment with eltanexor/venetoclax * To assess the overall survival of patients * To assess the progression free survival (PFS) and duration of response (DOR) in patients treated with eltanexor/venetoclax Exploratory objectives: * To assess differential response between MDS and AML cohorts * To develop and evaluate a phenotypic flow-based assay to predict response to eltanexor/venetoclax * To assess the effect of mutational changes on response to eltanexor/venetoclax * To measure the rates of measurable residual disease with eltanexor/venetoclax OUTLINE: This is a dose-escalation study of eltanexor in combination with venetoclax. Patients receive eltanexor orally (PO) once per day (QD) for 5 days per week for 14, 21, or 28 days every cycle, and venetoclax PO QD on days 1-14 of each cycle. Cycles repeat every 28 days in the absence of disease progression or unacceptable toxicity. Patients undergo bone marrow aspiration and biopsy and blood sample collection throughout the study. After completion of study treatment, patients are followed up every 3 months for up to 24 months.