Signaling Mutations Negate the Favorable Impact of NPM1 Mutations in Older Patients With Newly Diagnosed Acute Myeloid Leukemia Treated With VEN/HMA.

Frameshift mutations in exon 12 of nucleophosmin 1 (NPM1 mut) are among the most common mutations in acute myeloid leukemia (AML) and have historically been considered favorable-risk in the absence of FLT3-ITD. In the European LeukemiaNet (ELN) 2024 risk-classification for patients treated with hypomethylating agents plus venetoclax (HMA + VEN), NPM1 mut is not considered favorable when co-occurring with signaling gene (SG) mutations (i.e., FLT3-ITD, NRAS, KRAS). However, due to limited numbers in the original analysis, the prognostic impact of SG mutations in NPM1-mutant AML remains unclear. We evaluated the prognostic significance of NPM1 mut with and without SG mutations in two independent cohorts of patients ≥ 60 years with ELN 2024 favorable- or intermediate-risk AML treated with HMA + VEN. Cohort 1 included 322 patients treated in the academic setting. NPM1 mut (n = 61) was associated with a nonsignificantly longer overall survival (OS) compared to NPM1 wild-type (NPM1 wt) (median, 53.05 vs. 17.03 months, p = 0.10). In multivariable analysis (MVA), SG mutations were not independently prognostic within the NPM1 mut subgroup. Cohort 2 included 816 patients from a real-world community-treated cohort. NPM1 mut (n = 124) had a longer OS compared with NPM1 wt (median, 15.3 vs. 14.4 months, p = 0.03). In MVA, NRAS, KRAS, and FLT3-ITD were independent unfavorable prognostic factors; NPM1 mut with, compared to without, SG co-mutation had a shorter OS (median, 9.4 vs. 31.6 months, p = 0.001). These findings suggest SG mutations negate the favorable impact of NPM1 mut in older patients treated with HMA + VEN. Prospective clinical trials are needed to investigate the use of combination therapies to improve outcomes in this high-risk subgroup.