Pharmacogenomic Score Effectively Personalizes Treatment of Acute Myeloid Leukemia.

Abstract

Cytarabine (also known as ara-C) has been the backbone of acute myeloid leukemia (AML) chemotherapy for over five decades. Recent pharmacogenomics-based 10-SNP ara-C score (ACS10) showed low ACS10 (£0) to be associated with poor outcome in AML patients treated with standard chemotherapy. Here, we evaluated ACS10 score in the context of three different induction 1 regimens in pediatric AML patients. ACS10 score groups (low,£0 or high,>0) were evaluated for association with event-free survival (EFS) and overall survival (OS) by three randomized treatment arms in patients treated on the AML02 (NCT00136084) and AML08 (NCT00703820) clinical trials: AML02 low-dose cytarabine (LDAC arm, n=91), AML02+AML08 high-dose cytarabine (HDAC arm, n=194) and AML08 clofarabine+ cytarabine (Clo/Ara-C arm, n=105) induction 1 regimens. Within the low-ACS10 score (£0) group, significantly improved EFS and OS was observed among patients treated with Clo/Ara-C as compared to LDAC (EFS, HR=0.45, 95% CI, 0.23-0.88, p=0.020; OS, HR=0.44, 95% CI, 0.19-0.99, p=0.048). In contrast, within the high-ACS10 score group (score >0) augmentation with Clo/Ara-C was not favorable as compared to LDAC (Clo/Ara-C vs. LDAC, EFS, HR=1.95, 95% CI: 1.05-3.63, p=0.035; OS HR=2.17, 95%CI: 1.05-4.49; p=0.037). Personalization models predicted 9% improvement in outcome in ACS10 score-based tailored induction (Clo/Ara-C for low and LDAC for high-ACS10 groups) as compared to non-personalized approaches (p<0.002). Our findings suggest that tailoring induction regimens using ACS10 scores can significantly improve outcome in patients with AML. Given the SNPs are germline, preemptive genotyping can accelerate matching the most effective remission induction regimen.