PRIMARY OBJECTIVE:
I. To determine recommended phase 2 dose (RP2D) of actinium Ac 225 lintuzumab (lintuzumab-Ac225) when used in combination with venetoclax and decitabine and cedazuridine (ASTX-727).
SECONDARY OBJECTIVES:
I. To determine the maximum tolerated dose of lintuzumab-Ac225 when used in combination with venetoclax and ASTX-727.
II. To describe the frequency and severity of adverse events of patients treated on study, including cytopenia and organ toxicity after second dose of lintuzumab-Ac225.
III. To determine the rate and time to complete remission (CR), complete remission with incomplete hematologic recovery (Cri), and complete remission with partial hematologic recovery (CRh).
IV. To determine the rate and time to achieve CR/Cri/CRh without minimal residual disease (MRD) by multiparameter flow cytometry (MFC).
V. To determine the duration of remission, event-free and overall survival of patients.
VI. To evaluate and compare the clinical activity and toxicity between two lintuzumab-Ac225 administration schedules.
EXPLORATORY OBJECTIVES:
I. To correlate CD33 expression on AML cells with response to lintuzumab-Ac225 in combination with venetoclax and ASTX-727.
II. To evaluate CD33 isoforms as a variable for response to lintuzumab-Ac225 combination with venetoclax and ASTX-727.
OUTLINE: This is a dose-escalation study of lintuzumab-Ac225 in combination with venetoclax and ASTX-727. During dose-escalation phase, patients are randomized to 1 of 2 schedules.
SCHEDULE 1:
INDUCTION: Patients receive lintuzumab-Ac225 intravenously (IV) over 30 minutes on day 8, venetoclax orally (PO) once daily (QD) on days 1-28 and ASTX-727 PO QD on days 1-5 of cycle 1.
RE-INDUCTION: Patients with CR, partial response (PR) or no response (NR) after cycle 1 receive lintuzumab-Ac225 IV over 30 minutes on day 8, venetoclax PO QD on days 1-28 and ASTX-727 PO QD on days 1-5 of cycle 2.
MAINTENANCE/CONSOLIDATION: Patients with CRi, CRh, or morphologic leukemia-free state (MLFS) after cycle 1 receive venetoclax PO QD on days 1-28 and ASTX-727 PO QD on days 1-5 of each cycle. Cycles repeat every 28 days in the absence of disease progression or unacceptable toxicity.
Additionally, patients undergo bone marrow aspiration and biopsy and blood sample collection throughout the study.
SCHEDULE 2:
INDUCTION: Patients receive lintuzumab-Ac225 V over 30 minutes on day 1, venetoclax PO QD on days 1-28 and ASTX-727 PO QD on days 1-5 of cycle 1.
RE-INDUCTION: Patients with CR, PR or NR receive lintuzumab-Ac225 IV over 30 minutes on day 1, venetoclax PO QD on days 1-28 and ASTX-727 PO QD on days 1-5 of cycle 2.
MAINTENANCE/CONSOLIDATION: Patients with CRi, CRh, or MLFS after cycle 1 receive venetoclax PO QD on days 1-28 and ASTX-727 PO QD on days 1-5 of each cycle. Cycles repeat every 28 days in the absence of disease progression or unacceptable toxicity.
Additionally, 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 5 years.