Five-year final results of a phase III study of CPX-351 versus 7+3 in older adults with newly diagnosed high-risk/secondary AML.

Abstract

7510 Background: CPX-351 (Vyxeos; daunorubicin and cytarabine liposome for injection), a dual-drug liposomal encapsulation of cytarabine [C] and daunorubicin [D], is approved by the FDA and EMA for the treatment of adults with newly diagnosed therapy-related AML or AML with myelodysplasia-related changes. Primary analysis of the pivotal phase 3 study (NCT01696084) that formed the basis for these approvals evaluated patients (pts) aged 60-75 y with newly diagnosed high-risk/secondary AML and found that CPX-351 significantly improved median overall survival (OS) vs conventional 7+3, with a comparable safety profile. Here, we report the prospectively planned final 5-y follow-up results from this phase 3 study. Methods: Pts were randomized 1:1 to receive ≤2 induction cycles of CPX-351 (100 units/m2 [C 100 mg/m2 + D 44 mg/m2] as a 90-min infusion on Days 1, 3, 5 [2nd induction: Days 1, 3]) or 7+3 (C 100 mg/m2/d continuously for 7 d + D 60 mg/m2 on Days 1-3 [2nd induction: 5+2]). Pts achieving complete remission (CR) or CR with incomplete platelet or neutrophil recovery could receive up to 2 consolidation cycles. Pts could receive a hematopoietic cell transplant (HCT) at the physician’s discretion. Pts were followed until death or up to 5 y following randomization. Results: In total, 309 pts were randomized to CPX-351 (n = 153) or 7+3 (n = 156). The survival rate at 5 y was higher for CPX-351 vs 7+3 (18% vs 8%; Table). Among pts who died, the most common primary cause of death was progressive leukemia in both arms (CPX-351: 56%; 7+3: 53%). After a median follow-up of 60.65 mo, improved median OS with CPX-351 vs 7+3 was maintained: 9.33 vs 5.95 mo; Kaplan-Meier (KM) OS curves plateaued at ~30 mo. HCT was received by 53 (35%) vs 39 (25%) pts after CPX-351 vs 7+3; among these pts, the survival rate at 5 y was higher for CPX-351 vs 7+3 (52% vs 23%), and median OS landmarked from the HCT date was not reached for CPX-351 vs 10.25 mo for 7+3 (Table). Conclusions: After 5 y of follow-up, improved OS was maintained in this phase 3 study, supporting that CPX-351 has the ability to produce or contribute to long-term remission and survival in older pts with newly diagnosed high-risk/secondary AML. Clinical trial information: NCT01696084 . [Table: see text]