The relapsed and refractory acute myeloid leukemia’s optimal salvage chemotherapy regimen stays unclear. As a result, the probable assessment of the effectiveness and safety of the purine analog cladribine in combination with granulocyte colony-stimulating factor (G-CSF), low-dose cytarabine, and aclarubicin (C-CAG) regimen for patients with relapsed and refractory acute myeloid leukemia was done in the phase II study. For salvage treatment, thirty-four patients were administered the C-CAG regimen. Their treatment included cladribine 5 mg/m2, days 1–5; G-CSF 300 μg, days 0–9; aclarubicin 10 mg, days 3–6; cytarabine 10 mg/m2 every 12 hours, subcutaneously, days 3–9; 4 weeks per cycle. If complete remission (CR) was not reached after receiving two courses of chemotherapy, the patients were permitted to pull out of the study. Allogeneic hematopoietic stem cell transplantation was suggested to patients who entered complete remission, given that the conditions were correct. Else, they were treated for 24 weeks unless the researchers noticed any disease progression or the patients wanted to withdraw from the treatment.

At least two cycles of the C-CAG regimen were administered to all patients in the study. After eight weeks, twenty-three patients (67.6%) entered complete remission and five patients (14.7%) had partial remission. The 1-year overall survival (OS) was 59.7% (95% CI, 42.6%–76.8%), and disease-free survival (DFS) rates was 72.9% (95% CI, 54.3%–91.5%) at the median follow-up of 15 months (range is 3 to 38 months)

The C-CAG regimen is considerably successful against relapsed and refractory acute myeloid leukemia as suggested by the initial data. It also showed high rates of remission and low hematological toxicity. As a result, C-CAG might be used as an alternative treatment for relapsed and refractory acute myeloid leukemia.