Impact of Genetic Variation on Response to GO Therapy in COG-AML Trials AAML03P1 and AAML0531

The 340 de novo Acute Myeloid Leukemia (AML) patients (ages 1 month to 21 years) were enrolled in COG-AAML03P1 (NCT00070174). Everyone received standard chemotherapy regimen of ara-C, daunorubicin and etoposide (ADE) with addition of one 3 mg/m2 dose of Gemtuzumab Ozogamicin (GO) in induction 1 as well as in intensification II phase. The 1022 de novo AML patients (ages 0–30 years) were enrolled in COG-AAML0531 (NCT01407757). They were randomly assigned to receive either the standard ADE regimen (ADE arm, n = 511) or with the addition of one 3 mg/m2 dose of GO, during induction I as well as intensification II phase (ADE+GO arm, n = 511). Detailed study design, treatment regimen, and clinical outcomes of these two trials have been previously published (Cooper TM, Franklin J, Gerbing RB, et al., PMID:21766293 and Gamis AS, Alonzo TA, Meshinchi S, et al., PMID:25092781). The current study used genomic DNA from 1,225 pediatric patients treated in these two trials with 470 patients treated with standard chemotherapy in COG-AAML0531 (ADE arm) and 755 patients treated with addition of GO to standard therapy in COG-AAML03P1 and COG-AAML0531 trials (ADE+GO arm). The 132 SNPs in 42 genes within DNA-damage repair (DDR) pathways or genes implicated in mediating calicheamicin were selected for genotyping. These SNPs were genotyped using the Sequenom platform at the Biomedical Genomics Center, University of Minnesota. All SNPs had a call rate of more than 0.98 and were in accordance with the Hardy–Weinberg equilibrium. These genotypes were used to test for association with clinical endpoints as defined in the COG-AAML03P1 and COG-AAML0531 trials.]]>
Inclusion and exclusion criteria for completed trial COG-AAML03P1 (NCT00070174): Included patients were between ≥1 month and ≤21 years old with primary AML diagnosed per the FAB classification system. Patients with acute promyelocytic leukemia (APL), juvenile myelomonocytic leukemia, known bone marrow (BM) failure syndromes, Down syndrome, or secondary/treatment-related leukemia were excluded. Patients with myelodysplastic syndrome (MDS) were eligible if karyotypic abnormalities characteristic of de novo AML were present.Inclusion and exclusion criteria for completed trial COG-AAML0531 (NCT01407757): Included patients were between ≥1 month to 30 years with previously untreated primary AML. Previous exposure to chemotherapy except intrathecal cytarabine, APL, juvenile myelomonocytic leukemia, BM failure syndromes, or secondary AML were the excluded.]]>