Impact of AML1/ETO Fusion on the Efficacy of Venetoclax Plus Hypomethylating Agents in Newly Diagnosed Acute Myeloid Leukemia.

BACKGROUND

AML1/ETO fusion confers favorable prognosis in acute myeloid leukemia (AML) treated with intensive chemotherapy (IC). However, the impact of AML1/ETO fusion on the efficacy of venetoclax in the treatment of AML is unclear.

OBJECTIVE

The aim of this study was to evaluate the efficacy of venetoclax plus hypomethylating agents (VEN/HMAs) in patients with AML1/ETO-positive AML.

PATIENTS AND METHODS

Patients with newly diagnosed AML in two centers were reviewed and divided into three cohorts: AML1/ETO-positive AML treated with frontline VEN/HMA (Cohort A), AML1/ETO-negative AML treated with frontline VEN/HMA (Cohort B), or AML1/ETO-positive AML treated with frontline IC (Cohort C). The response and survival were compared between the cohorts.

RESULTS

A total of 260 patients were included in the study. Patients in Cohort A had a significantly lower overall response rate (ORR) than patients in Cohort B (40.9% vs 71.2%, p = 0.005). The median event-free survival (EFS) in Cohort A and Cohort B was 2.7 months and 7.7 months, respectively, with no significant difference. The ORR and median EFS in Cohort C were 80.8% and 14.9 months, respectively, which were significantly superior to those in Cohort A, and the advantages remained significant after propensity score matching. ORR and EFS in KIT-mutated patients with AML1/ETO-positive AML receiving VEN/HMA were much inferior to those in KIT wild-type patients (ORR 0.0% vs 81.8%, p = 0.001; EFS 1.2 months vs not reached, p < 0.001).

CONCLUSIONS

Newly diagnosed AML patients with AML1/ETO fusion had a poor response to frontline VEN/HMA treatment. When determining induction therapy for patients with AML1/ETO-positive AML, IC should be preferred over VEN/HM.