A Multicenter Randomized Non-Inferiority Study of Homoharringtonine Versus Etoposide in Induction Phase for Chinese Childhood Acute Myeloid Leukemia - a Report from China Children's Leukemia Group (CCLG)

Abstract

Purpose: Classical introduction therapy of etoposide combined with cytarabine and daunorubicin (DAE) is commonly applied in childhood acute myeloid leukemia (AML), but etoposide has an increasing risk of secondary cancer. In this study the non-inferiority effect of homoharringtonine (H) versus Etoposide was compared in induction phase for Chinese childhood AML treated by CCLG-AML 2015 protocol. Patients and Methods: The total of 818 childhood AML patients (median age of 80 months; range from 1 to 193 months) from CCLG-AML 2015 study group (40 centers) were randomly allocated to two induction arms of DAE and DAH. During the course of induction I, 467 patients in DAE group received daunorubicin and cytarabine (DA) plus etoposide (D: 40 mg/m2 per day on days 1, 3 and 5; A: 100 mg/m2 every 12 hours from day 1 to 7; E: 100 mg/m2 per day from days 1 to 5), and 351 patients in DAH group received the same DA does plus homoharringtonine ( H: 3 mg/m2 per day from days 1 to 5). During the course of induction II, Idarubicin (10 mg/m2 per day on days 1, 3 and 5) was used to instead of daunorubicin, and patients accepted corresponding IAE or IAH treatment. All patients were divided into standard, intermediate or high risk group (SR, IR or HR group) according to CCLG-AML 2015 regimen (table 1). They were assessed by bone marrow (BM) aspiration and morphologically defined complete remission (CR: blasts ≤5%), partial remission (PR: blasts between 6~19%), or non-remission (NR: blasts ≥20%) on days 28 of induction. Results: DAH/IAH group showed non-inferiority for remission rates both in induction Ⅰ (DAE 70.2% vs DAH 76.6%, P = 0.041) and induction Ⅱ (IAE 79.4% vs IAH 87.7%, P = 0.016). Total CR rate at end of induction Ⅰ reached 73.0% and it didn't differ between DAE and DAH group for IR or HR group (IR group: DAE, 73.9% vs. DAH, 77.3%, P = 0.529; HR group: DAE, 53.9% vs. DAH, 62.6%, P = 0.128). But for SR group, CR rate of DAH group is significantly higher than DAE group (DAE, 85.1% vs. DAH, 95.1%, P = 0.013). It has similar results after induction Ⅱ. Total CR rate reached 83.1% and all patients has almost gained CR/PR for SR or IR group, only 2 patients still couldn't obtain remission. There was no significant difference in SR or IR group between two arms, but for HR group, CR rate significantly increased in those who accepted IAH chemotherapy (SR group: IAE, 91.2% vs. IAH, 95.0%, P = 0.398; IR group: IAE, 87.1% vs. IAH, 92.5%, P = 0.275; HR group: IAE, 66.1% vs. IAH, 78.8%, P = 0.050). Conclusion: Homoharringtonine is an effective cytotoxic drug and DAH regimen showed non-inferiority induction effect compared with classical DAE regimen in childhood AML, especially for patients of standard risk group. Disclosures No relevant conflicts of interest to declare.