Cladribine in Combination with Standard Daunorubicine and Cytarabine (DAC) as a Remission Induction Treatment Improves the Overall Survival in Untreated Adults with AML Aged < 60 y Contrary to Combination Including Fludarabine (DAF): A Multicenter, Randomized, Phase III PALG AML 1/2004 DAC/DAF/DA Study in 673 Patients-A Final Update.

Abstract 2055

Poster Board II-32

This trial is a continuation of earlier Polish Adult Leukemia Group (PALG) studies on the use of purine analogues for therapy of AML patients (Leukemia 2004,18:989–97, updated at 7 y: ASH 2006, Abstr.N#2003, Ann Hematol. 2008, 87:361–7).

The goal of the present study was to evaluate the efficacy of combination including fludarabine – DAF (daunorubicine 60 mg/m2/d iv, d 1–3; cytarabine (AraC) 200 mg/m2/d ci, d 1–7, and fludarabine 25 mg/m2 iv d 1–5) in untreated adult patients with AML, based on head to head comparison with DAC (DNR, AraC, Cladribine), and standard DA regimens (preliminary results: ASH 2008, abstr.#133).

Primary end-points were: complete remission rate (CR) and overall survival (OS); secondary objectives were: toxicity and leukemia-free survival (LFS). Patients achieving CR received two courses of subsequent intensive consolidation: HAM (HD AraC, mitoxantrone) and HD AraC. Reduction of consolidation was accepted in patients treated with early alloBMT. In case of partial remission (PR) after the first induction course the same regimen was repeated. Patients with no remission (NR) or with PR after 2 induction courses were withdrawn from the study.

Between 09.2004 and 05.2008, 673 adult untreated AML patients aged 18–60 y, median 47 y, sex: male 49,5%, female 50,5%, treated in 18 co-operating PALG centers were centrally randomized to either DAF (n=225), DAC (n=224) or DA (n=224) arm (1:1:1). PML/RAR alfa positive - FAB M3 cases were excluded. The study groups were well balanced in respect of age, sex, FAB subtype, and WBC. The results are summarized in the table.

Both, the entire CR rate and the CR rate after a single induction course were significantly superior in the DAC arm if compared with DA and DAF subgroups. With a median follow-up of 34 months (the longest observation time 5y) the OS rate equaled 46% for the DAC treated subgroup and was higher in comparison to the standard DA arm and the DAF arm. There were no significant differences in the leukemia free survival rates. The early death rates of 8,5–11%. were similar in the studied treatment subgroups. All patients developed WHO grade IV thrombocytopenia and agranulocytosis. The frequency and severity of infections, mucositis, vomiting, diarrhoea, alopecia, polyneuropathy as well as of cardiac, liver or kidney dysfunctions were comparable in particular arms.

In conclusion, this updated results of randomized study prove that the incorporation of cladribine to the standard DA induction regimen (DAC) improves CR rate and the overall survival in adults with AML aged up to 60 y, without additional toxicity. This beneficial effect was not observed in patients treated using the DAF protocol with fludarabine added to the standard “DA 3+7” schedule.