Clinical outcomes after CPX-351 in patients with high-risk acute myeloid leukemia: A comparison with a matched cohort from the Spanish PETHEMA registry.

Background: CPX-351 is approved for the treatment of therapy related acute myeloid leukemia (t-AML) and AML with myelodysplastic related changes (MRC-AML). The benefits of this treatment over standard chemotherapy has not been addressed in well matched cohorts of real-life patients.

Methods: Retrospective analysis of AML patients treated with CPX-351 as per routine practice. A propensity score matching (PSM) was used to compare their main outcomes with those observed in a matched cohort among 765 historical patients receiving intensive chemotherapy (IC), all of them reported to the PETHEMA epidemiologic registry.

Results: Median age of 79 patients treated with CPX-351 was 67 years old (interquartile range 62-71), 53 were MRC-AML. The complete remission (CR) rate or CR without recovery (CRi) after 1 or 2 cycles of CPX-351 was 52%, 60-days mortality 18%, measurable residual disease <0.1% in 54% (12 out of 22) of them. Stem cell transplant (SCT) was performed in 27 patients (34%), median OS was 10.3 months, and 3-year relapse incidence was 50%. Using PSM, we obtained two comparable cohorts treated with CPX-351 (n = 52) or IC (n = 99), without significant differences in CR/CRi (60% vs. 54%) and median OS (10.3 months vs. 9.1 months), although more patients were bridged to SCT in the CPX-351 group (35% vs. 12%). The results were confirmed when only 3 + 7 patients were included in the historical cohort. In multivariable analyses, SCT was associated with better OS (HR 0.33 95% CI: 0.18-0.59), p < 0.001.

Conclusion: Larger post-authorization studies may provide evidence of the clinical benefits of CPX-351 for AML in the real-life setting.