ATLANTA — Patient age, baseline bone marrow blasts, platelet and WBC counts, and geography all modulate overall survival (OS) benefits associated with decitabine for patients diagnosed with acute myeloid leukemia (AML) at age ≥65 years, according to analysis of data from a multinational Phase 3 trial presented during the 54th American Society of Hematology (ASH) Annual Meeting and Exposition.
“Treatment response is related to both patient and disease status in older patients with AML,” reported lead author Professor Jiří Mayer, MD, PhD, of the Department of Internal Medicine, Hemato-Oncology, University Hospital Brno and Masaryk University, Brno, Czech Republic. In older patients with AML, overall survival was associated with the prognostic factors of age, ECOG PS (Eastern Cooperative Oncology Group Performance Status), cytogenetic risk, baseline bone marrow blasts, baseline platelet counts, and baseline WBC in addition to responding differently to decitabine versus patient treatment choice, supportive care, or cytarabine.
The phase 3 trial compared decitabine and supportive care or low-dose cytarabine (TC) in newly diagnosed de novo or secondary AML among older adults (age ≥65 years), with poor- or intermediate-risk cytogenetics. Of 485 study participants, 242 were randomized to receive decitabine and 243 to receive TC (cytarabine n=215; supportive care n=28), the authors reported.
“Patient characteristics that appeared to adversely affect OS at the 0.05 level included more advanced age, poorer baseline ECOG status, poor cytogenetics, higher bone marrow blast count, low baseline platelet count, high WBC count, and geographic region (Western vs Eastern Europe),” Dr. Mayer explained.
OS hazard ratios (HRs) were for decitabine vs TC, 0.80 (95% CI, 0.65-0.98; P=0.03); age 70-74 years vs <70 years (HR 1.31; 95% CI, 1.0-1.71; P=0.047); age ≥75 years vs < 70 years (HR 1.56; 95% CI, 1.20-2.03; P=0.001); intermediate vs poor baseline cytogenetic risk (HR 0.70; 95% CI, 0.57-0.87; P=0.001); baseline ECOG PS 0/1 vs 2 (HR 0.77; 95% CI, 0.61-0.98; P=0.032); Eastern vs Western Europe (HR 0.65; 95% CI, 0.48-0.88; P=0.005); baseline bone marrow blast >50% vs ≤50% (HR 1.36; 95% CI, 1.10-1.67; P=0.005); baseline platelets (109/L; [HR 0.78; 95% CI, 0.66-0.91; P=0.002]); and baseline WBC (109/L; [HR 1.26; 95% CI, 1.05-1.51; P=0.015]).
“Subgroup analyses suggest a greater response to decitabine vs cytarabine or standard care in patients aged ≥75 years, a population that is traditionally difficult to treat, with a poor prognosis,” noted Dr. Mayer.