Aim: To make a randomized comparison of 2 consolidation treatment options (two patient groups): 2 cycles of cytarabine in average (Ig/m2 in Group 2) and standard (100 mg/mi2 in Group 1) doses in combination with idarubicin (8-12 mg/m2) and mitoxantrone (10 mg/m2), after two 7+3 induction cycles of daunorubicin (60 mg/mi2) and subsequent 6 cycles of maintenance therapy.
Subjects and methods: In January 2010 to October 2013, a Russian multicenter trial was conducted to treat patients with acute myeloid leukemias (AML) in accordance with the AML-01.10 protocol (ClinicalTrials.gov Identifier: NCT01587430). The trial enrolled 243 AML patients from 21 centers, including 71 patients (median age 38 years) from the State Hematology Center, Ministry of Health of the Russian Federation; 35 and 36 patients were randomized to Groups 1 and 2, respectively. The randomized groups were balanced by basic clinical and laboratory parameters. Favorable, intermediate, and high cytogenetic prognoses were in 14 (21.9%), 40 (62.5%), and 10 (15.6%) patients, respectively.
Results: Prior to treatment, 2 patients died; one patient refused treatment. Fifty-eight (85.3%) of the 68 patients achieved complete remission (CR); early deaths was in 2 (2.9%) and resistance in 8 (11.8%). Four (6.9%) patients died during CR. Protocol deviations (doses, intervals, and the number of cycles) were recorded in 12 (20.7%) of the 58 patients. Other 8 (11.8%) patients were switched to low-dose cytarabine because of complications, withdrawn from the protocol and not included into the analysis of randomized comparison. Twenty allogeneic bone marrow transplantations (allo-BMT) (7 related, 12 unrelated, and 1 haploidentical) were performed; of them 15 allo-BMTs were done during first CR. In the 68 patients, 3-year overall survival (OS) was 45.6%; relapse-free survival (RFS) was 41.5%. OS was 64.6% in Group 1 and 58.3% in Group 2; RFS was 62 and 38.8% in Groups 1 and 2, respectively (p>0.5). In the favorable, intermediate, and high prognosis groups, OS was 79.5, 60, and 31.1% and RFS was 81.8, 41.3, and 33.3%, respectively (p=0.1). The consolidation treatment option unchanged survival rates in the above risk groups. Unachieved CR after the first cycle considerably decreased RFS (33.9% versus 60%) and served as an indication for allo-BMT during first CP (RFS without BMT was 0; that with BMT was 78%).
Conclusion: No differences were found between both consolidation options according to long-term results. Protocol deviations were recorded in one-third of the patients. While implementing the protocol, the efficiency of treatment was high. Allo-BMT during first CR substantially increased RFS if CP was not achieved after the first cycle.