Maintenance Treatment with 5-Azacitidine in Patients with Acute Myeloblastic Leukemia Ineligible for Intensive Treatment and with Response After Induction Chemotherapy: A Phase II Clinical Trial.

Background/Objectives: After first-line treatment, elderly patients with acute myeloid leukemia (AML) often become unfit to continue intensive chemotherapy despite having achieved a response. This trial aimed to determine the efficacy of maintenance treatment with azacitidine in AML patients who are ineligible to continue intensive treatment after remission. Methods: A single-arm, multicenter, phase II clinical trial (EudraCT: 2010-020432-18) including patients with AML with complete (CR) or partial remission (PR) after one or two cycles of intensive induction chemotherapy and ineligible to continue intensive treatment was conducted. Efficacy was measured as the response rate, progression-free survival (PFS), and overall survival (OS), and was assessed in the intention-to-treat (ITT) population (all patients). Quality of life was also assessed. Results: Thirty-two patients were included, with a mean age of 73.3 years (SD 3.8) (53.1% male); sixteen patients (50.0%) reached the sixth treatment cycle. The best response was CR in 11 patients (68.8%) and PR in 2 patients (12.5%) at cycle six, and CR in 15 patients (46.9%) and PR in 5 patients (15.6%) overall. The median PFS was 6.7 months (95% CI 3.1-8.7), and OS was 11.5 months (95% CI 6.6-15.9). The daily function (p = 0.0296), cognitive function (p = 0.0412), and social function (p = 0.0275) scales of the EORTC QLQ-C30 questionnaire significantly improved. Thirty-one patients (96.9%) experienced adverse events; six (1.9%) were serious. Conclusions: Azacitidine is a safe and well-tolerated maintenance treatment option for AML patients unfit for intensive therapy following a response to induction, although the single-arm phase II design precludes direct causal inference. Patients achieved promising results regarding PFS and remission rates, with improved quality of life.