Homoharringtonine Added to Venetoclax and Azacitidine Improves Outcome and Mitigates Genetic Impact in Relapsed/Refractory AML: A Multi-center Cohort Study

Abstract Purpose: We investigated whether homoharringtonine (HHT) added to venetoclax (VEN) plus azacitidine (VA) could improve outcomes and counteract the negative effects of genetic patterns in patients with relapsed/refractory acute myeloid leukemia (RR-AML). Experimental Design: A multi-center, retrospective, cohort study of the response and genetic patterns of response to the VA plus HHT (VAH) versus the VA regimens as salvage treatment in patients with RR-AML was performed. The endpoints were the rates of composite complete remission (CRc), measurable residual disease (MRD), event-free survival (EFS), overall survival (OS), and relapse between VAH and VA groups. Results: A total of 321 patients (VAH, n=172; VA, n=149) were analyzed. Compared to VA, VAH significantly improved the rates of CRc (44.3% vs. 66.3%, P<0.001), MRD-negativity (34.8% vs. 59.3%, P=0.002), prolonged OS (median: 15.1 months vs. not reached, P <0.001), and EFS (median: 3.8 vs. 13.0 months, P<0.001). VAH significantly mitigated the negative impact on VA efficacy of mutated FLT3-ITD/TKD, N/KRAS, and t(8;21)/AML1-ETO, as well as the relatively unfavorable effects of the TET2 and DNMT3A mutations. VAH significantly enhanced the response of patients with non-adverse European LeukemiaNet (ELN) risk, with a trend towards improved response in those with adverse ELN risk, complex karyotype, and DNMT3A+FLT3+NPM1+. The incidence of grade 3 or higher adverse events was comparable between the two groups. Conclusions: Our findings suggest the addition of HHT to VA might enhance response and mitigate the negative impact of certain genetic patterns in RR-AML while being well tolerated.