Inhibition of MDM2 Improves the Therapeutic Effect of Hypomethylating Agents in Myelodysplastic Syndromes (MDS) and Chronic Myelomonocytic Leukemia (CMML)

Hypomethylating agents (HMA) are the current standard care for MDS and CMML. However, a large proportion of patients experience HMA treatment failure that is associated with poor prognosis. Novel treatments are urgently needed for these diseases. We performed next generation sequencing (NGS) based mutation profiling that targeted the 81 most frequently mutated genes in baseline bone marrow (BM) mononuclear cells (MNCs) from patients with MDS and CMML (N=83) prior to HMA treatment. Analysis of impact of the mutations on outcomes of HMA treatment indicated that patients with TP53 mutations (N=22) had significantly worse overall survival (HR = 3.29; P < 0.05; q < 0.05). This result is consistent with previous reports and suggests that strengthening the activity of wild type (WT) TP53, through strategies such as inhibition of TP53 negative regulator MDM2, may improve therapeutic efficacy of HMAs in patients with MDS and CMML.