A Study of Experimental Combination of CPX-351 and Gemtuzumab Ozogamicin For Relapsed Acute Myeloid Leukemia

This phase Ib trial studies the best dose of gemtuzumab ozogamicin when given together with CPX-351 in treating patients with acute myeloid leukemia that has come back after it was previously in remission. CPX-351 is a chemotherapy, which works in different ways to stop the growth of cancer cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Gemtuzumab ozogamicin is a monoclonal antibody, called gemtuzumab, linked to chemotherapy called calicheamicin. Gemtuzumab attaches to CD33 (transmembrane receptor) positive cancer cells in a targeted way and delivers ozogamicin to kill them. Giving CPX-351 and gemtuzumab ozogamicin may work better in treating patients with acute myeloid leukemia, compared to giving only one of these therapies alone.

PRIMARY OBJECTIVES:

1. To determine the phase II dose of the combination liposome-encapsulated daunorubicin-cytarabine (CPX-351) plus gemtuzumab ozogamicin (GO) by means of estimating maximum tolerated dose (MTD) in participants with relapsed acute myeloid leukemia (AML).

SECONDARY OBJECTIVES:

1. To estimate the remission rate (complete remission plus complete remission with incomplete hematologic recovery) of participants in the MTD cohort who receive CPX-351 plus GO.

II. To evaluate CPX-351 plus GO as a bridge to allogeneic hematopoietic stem cell transplantation (HSCT) in participants with relapsed AML.

III. To estimate the duration of remission. IV. To evaluate for toxicity by means of Common Terminology Criteria for Adverse Events (CTCAE) version 4.03.

1. To evaluate for the development of veno-occlusive disease at any point during the study in participants treated with CPX-351 plus GO.

VI. To evaluate time to return of normal hematopoiesis after induction therapy. VII. To evaluate 30- and 60-day survival.

EXPLORATORY OBJECTIVES:

1. To evaluate if there is a difference in remission rate based on CD33 splicing single nucleotide polymorphism (SNP) genotype (CC, TC, or TT) in participants receiving CPX-351 plus GO.

II. To evaluate the impact that leukemia cell multidrug resistance activity have on achieving remission after treatment with CPX-351 plus GO.

III. To evaluate the possible associations of participant constitutional genotype, leukemia genotype, and response to therapy.

IV. To evaluate the possible associations of participant ribonucleic acid (RNA) expression, leukemia RNA expression, and response to therapy.

OUTLINE: This is a dose-escalation study of gemtuzumab ozogamicin when given in combination with liposome-encapsulated daunorubicin-cytarabine.

INDUCTION: Patients receive liposome-encapsulated daunorubicin-cytarabine intravenously (IV) over 90 minutes on days 1, 3, and 5, and gemtuzumab ozogamicin IV over 2 hours on day 7 in the first cohort of study participants, days 4 and 7 in the second cohort of study participants, or days 1, 4, and 7 in the third cohort of study participants, in the absence of disease progression or unacceptable toxicity. The dose expansion cohort will receive the above treatment schedule that is determined to be the maximum tolerated dose.

CONSOLIDATION: Patients who achieve complete remission (CR)/CR with incomplete hematologic recovery (CRi) receive consolidation therapy at the discretion of the treating physician and/or proceed to allogeneic HSCT.