Modified Intensive Induction Treatment for Elderly Acute Myeloid Leukemia Patients Based on Peripheral Blast Clearance Rate: A Phase II Single-Arm Study

• Published in: Blood 2021-11, Vol.138 (Supplement 1), p.1260-1260
• Main Authors: Li, Ya, Li, Xiaoyang, Zhu, Hongming, Zhang, Yunxiang, Chen, Yu, Chen, Qiusheng, Zheng, Yu, Li, Junmin
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2021-152042

Background Outcomes and prognosis of older patients with acute myeloid leukemia (AML) are fairly dismal and poor tolerance to regimens hinders treatment decision-making to expand to the greatest extent. Nevertheless, it is still indicated that a certain proportion of elder patients may benefit from intensive therapies [1], after which the insistent need for algorithms to select elder patients fit for intensive regimens has emerged. Based on the previous achievement, monitoring the peripheral blast clearance rate on the day 5 of induction chemotherapy (D5-PBCR) showed its promising value in younger patients [2]. Along with the increasingly important comprehensive geriatric assessment (CGA), we conducted this trial in fit elderly AML patients to confirm the non-inferior efficacy of modified intensive treatment on the basis of D5-PBCR. Materials and methods This multiple-center, single-arm, phase 2 trial of early intervention according to D5-PBCR results with modified “3+7” regimen was performed at Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine (Shanghai, China) and the other two hospitals in Shanghai. Patients aged 60-75 years were assessed via CGA and required to be fit for intensive chemotherapy. Eligible patients had newly diagnosed AML with more than 0·5% blasts detected in the peripheral blood and adequate end-organ function. The initial induction included idarubicin (6 mg/m² for 3 days) and cytarabine (100 mg/m² for 7 days). Peripheral blood specimens were collected before and on day 5 of induction and analyzed by multi-parameter flow cytometry to calculate the D5-PBCR. D5-PRCR (+) patients received extra IDA (6 mg/m² for 2 days) starting from induction day 6 with the absence of contraindications. Responders received another “2+5” regimens and at least two cycles of mediate dose cytarabine or even allogeneic stem cell transplantation, if eligible. The primary endpoint was composite complete remission (CR/CRi), and secondary endpoints were overall survival, event-free survival, early mortality, minimal residual disease after one cycle of induction, drug toxicity, and safety. The trial was registered in the Chinese Clinical Trial Register (ChiCTR-OPC-16008955). Results Between March 30, 2016, and June 30, 2021, a total of 120 eligible patients were enrolled in the trial (Fig.1). Fifty-nine (49.2%) patients were D5-PBCR (+), of which seventeen patients were ineligible for extra idarubicin due to severe infection or unstable