Survival outcomes with CPX-351 vs 7+3 by baseline bone marrow blast percentage in older adults with newly diagnosed high-risk or secondary acute myeloid leukemia: A 5-year follow-up study.

Abstract

7027 Background: CPX-351, a dual-drug liposomal encapsulation of daunorubicin and cytarabine in a synergistic 1:5 molar ratio, is approved for newly diagnosed therapy-related acute myeloid leukemia (AML) or AML with myelodysplasia-related changes in the US and Europe following positive efficacy and safety data from the pivotal phase 3 clinical trial (NCT01696084). A previous exploratory analysis of the trial data (median follow-up 20.7 months) showed improved survival outcomes with CPX-351 vs conventional 7+3 chemotherapy in adults with newly diagnosed high-risk or secondary AML (sAML) irrespective of baseline bone marrow (BM) blast percentage. Here we report 5-year follow-up data (median follow-up 60.9 months) to provide insights into the longer-term efficacy and safety of CPX-351 in these patient subgroups. Methods: Patients (60–75 years) with a pathologic diagnosis of AML (high-risk/sAML) per the WHO 2008 criteria (≥20% blasts in peripheral blood or BM) and an ECOG PS of 0–2 were randomized to receive CPX-351 or 7+3 chemotherapy. In these post hoc subgroup analyses at 5 years follow-up, overall survival (OS), event-free survival (EFS) and complete remission (CR) were assessed by baseline BM blast percentage. The analysis included patients with low ( < 20%) BM blasts to account for changes in blast count thresholds in the updated WHO AML classification. Results: Overall, median OS and EFS were longer with CPX-351 vs 7+3 in each subgroup; median OS was greatest in low blast subgroups for both treatments (Table). Higher CR rates were observed with CPX-351 vs 7+3 irrespective of baseline BM blasts. Median Kaplan-Meier (KM)-estimated survival rates increased with CPX-351 vs 7+3 across BM blast subgroups. The CPX-351 safety profile was comparable across BM blast subgroups and consistent with the known safety profile of 7+3. Conclusions: These 5-year follow-up data suggest that CPX-351 results in improved outcomes irrespective of baseline BM blast percentage vs conventional 7+3 chemotherapy in older adults with AML. Clinical trial information: NCT01696084 . [Table: see text]