Outcomes of older patients with NPM1-mutated AML: current treatments and the promise of venetoclax-based regimens

Abstract

Nucleophosmin-1 mutations (NPM1+) occur in ∼30% of acute myeloid leukemia (AML) patients. Although typically associated with favorable prognosis, the beneficial impact of NPM1+ decreases with increasing age in patients treated with standard intensive chemotherapy (IC) or hypomethylating agents (HMAs). This retrospective analysis compared outcomes of NPM1+ AML patients treated with 1 of 3 induction approaches: HMA plus BCL-2 inhibitor venetoclax (VEN), HMA, or IC therapy. Composite complete response (CRc: CR + CR with incomplete count recovery) was seen in 96% (27/28), 36% (17/47), and 89% (204/228) of HMA + VEN, HMA, and IC patients, respectively (HMA + VEN vs HMA, P < .001; HMA + VEN vs IC, P = .10). Older patients (age >65 years) treated with HMA + VEN, HMA, or IC had CR rates of 88%, 28%, and 56%, respectively (HMA + VEN vs HMA, P < .001; HMA + VEN vs IC, P = .01). Significant improvement in overall survival (OS) was seen in patients age >65 years treated with HMA + VEN vs HMA (not reached [NR] vs 0.4 years; P < .001) or IC (NR vs 0.93 years; P = .001). Older patients treated with HMA + VEN had OS of 80% after median 1-year follow-up, with estimated 2-year OS of 70%. In the multivariable Cox model analysis, HMA + VEN was associated with a 69% lower risk of death compared with IC (hazard ratio, 0.31; 95% confidence interval, 0.12-0.83; type I error-adjusted P = .038). HMA + VEN combinations demonstrated impressive results compared with traditional standard-of-care regimens in older patients with NPM1+ AML.