Infectious complications in patients with acute myeloid leukemia treated according to the protocol with daunorubicin and cytarabine with or without addition of cladribine. A multicenter study by the Polish Adult Leukemia Group (PALG).

Objectives: The addition of cladribine to the standard regimen consisting of daunorubicin and cytarabine has been reported to increase the efficacy of induction therapy in acute myeloid leukemia (AML). The goal of this study was to determine the effect of this modification on the incidence and spectrum of infectious complications.

Methods: Case report forms of 309 patients with newly diagnosed AML who had been enrolled in the prospective, randomized 'DAC-7 vs. DA-7' trial were reviewed. The frequency, etiology, localization, severity, and outcome of infections were compared for patients receiving only daunorubicin and cytarabine (DA-7) and those additionally treated with cladribine (DAC-7).

Results: A total of 443 febrile episodes were reported with no significant difference between the treatment groups. A trend towards a higher frequency of bacteremias was observed among DA-7 patients compared to those in the DAC-7 group (31% vs. 21%; p=0.08). The treatment arms did not differ in terms of the distribution of the isolated Gram-positive, Gram-negative, fungal, and viral organisms. However, when bacteremias were considered, Gram-positive blood cultures tended to be more frequent in the DA-7 compared to the DAC-7 group (16% vs. 8.5%; p=0.07). This difference reached statistical significance when major blood bacteremias were analyzed separately (13% vs. 5%; p=0.02). Complete recovery from infections was observed in the majority of patients across both treatment arms and no significant difference was noted regarding infection-related mortality.

Conclusions: The addition of cladribine to standard induction chemotherapy has no impact on the incidence and spectrum of infectious complications in newly diagnosed AML patients.