High Dose (HD-AraC) Vs Standard Dose Cytosine Arabinoside (SD-AraC) During Induction and IL-2 Vs Observation After Consolidation/Autologous Stem Cell Transplantation in Patients with Acute Myelogenous Leukemia (AML): Final Report of the AML-12 Trial of EORTC and GIMEMA Leukemia Groups on the Value of High Dose AraC
Authors: Willemze Roelof , Suciu Stefan , Mandelli Franco , Meloni Giovanna , Labar Boris , Halkes Stijn J.M. , Muus Petra , Mistrik Martin , Specchia Giorgina , Fabbiano Francesco , Nobile Francesco , Sborgia Marco , Camera Andrea , Selleslag Dominik , Lefrere Francois , Magro Domenico , Leone Giuseppe , Cantore Nicola , Beksac Meral , Berneman Zwi , Thomas Xavier , Melillo Lorella , Bron Dominique , Fillet Georges , Guimaraes Jose E. , Amadori Sergio , Fazi Paola , Karrasch Matthias , Vignetti Marco , de Witte Theo , Marie Jean-Pierre 
Published: October 2019

Abstract 257

The AML-12 randomized phase III trial of EORTC-LG and GIMEMA assessed the efficacy and toxicity of HD-AraC (3 g/sqm/12 hrs for 4 days) combined with daunorubicin (50 mg/sqm/d for 3 days) and etoposide (50 mg/sqm/d for 5 days) vs SD-AraC (100 mg/sqm/d for 10 days) with the same drugs, in previously untreated AML < 61 year old patients (APL excluded). Patients (pts) in complete remission (CR) had to receive consolidation consisting of AraC (500 mg/sqm/12 hrs for 6 days) and daunorubicin. Subsequently an allogeneic (allo-SCT) or autologous stem cell transplantation (auto-SCT) was planned according to donor availability and age. A 2nd randomization had to be done after evaluation of consolidation in pts without a donor: auto-SCT followed or not by low dose IL-2. The aim of the trial was to detect an 8% treatment difference (from 35% to 43%) in the 5-yr overall survival (OS) rate, corresponding to a hazard ratio (HR) of 0.80 (alpha=5%, power=95%); secondary endpoints were response to induction, toxicity, disease-free survival (DFS) from CR. Randomization was performed centrally; the 1st randomization was stratified for age (<46 vs > 45 yrs), performance status, WBC and center. Intent-to-treat analysis was done. From 9/1999 till 1/2008, 2005 pts from 68 centers were randomized. Due to insufficient reporting, 3 centers, who recruited 63 patients, have been excluded from the analysis. The remaining 1942 pts (872 pts entered by EORTC-LG and 1070 by GIMEMA) 969 were randomized in SD-AraC and 973 in HD-AraC arm; among them 25 and 28, respectively, were ineligible, but kept in the analysis. Both arms were comparable with respect to gender, age (median=45 yrs), disease history, initial leukocyte count, PS, FAB and cytogenetics. At a median follow up of 6 yrs, 1114 pts had died.

Results:

After 1 or 2 courses of induction, CR was achieved in 1430 pts (73.6%); 684 (71.9%) pts (SD-AraC group) vrs 746 (78.7%) pts (HD-AraC group): p=0.002. Resistance was documented in 173 (18.2%) vrs 123 (13%), and death during induction in 85 (8.9%) vrs 71 (7.5%) pts, respectively. Induction toxicity profile and grade was similar in the 2 arms except for conjunctivitis grade 3: HD-AraC>SD-AraC. CR rates for pts<46 yrs were 74.7% (SD-AraC) and 81.4% (HD-AraC) and for pts>45 yrs 66.4% (SD-AraC) and 71.8% (HD-AraC). 634 pts (SD-AraC and 686 (HD-AraC) received a consolidation cycle. Among 765 CR-pts<46 yrs 284 pts had an HLA identical sibling (<46D) and 481 did not or had not been typed (<46NoD). Among 665 CR-pts>45 yrs 225 pts had an HLA identical sibling (>45D) and 440 did not or had not been typed (>45NoD). In the <46D group 211 underwent an allo-SCT and 11 an auto-SCT. In the <46NoD group 274 underwent an auto-SCT and 29 a MUD-SCT; in the >45D group 147 underwent an allo-SCT and 14 an auto-SCT. In the >45NoD group 244 underwent an auto-SCT and 12 a MUD-SCT. Comparisons of treatments arm regarding OS from randomization, DFS and Survival (S) from CR are indicated in the Table.

The impact of age on the treatment difference regarding OS was almost significant (p=0.06). In pts >45 who reached CR, the decrease in the relapse rate in the HD-Ara-C arm vrs SD-Ara-C arm (45.5% vs 49.4%) was counterbalanced by an increase in the death in CR rate (18.4% vs 13.2%).

Conclusion:

The final evaluation of the EORTC-GIMEMA AML-12 trial shows that, with a median follow-up of 6 years, HD-AraC in the induction treatment leads to a significantly higher CR rate than SD-Ara-C and results in improvement in overall survival but only in pts under the age of 46 years.

Disclosures:

Muus: Amgen: Membership on an entity's Board of Directors or advisory committees. Beksac:Janssen Cilag: Honoraria, Speakers Bureau; Celgene: Honoraria, Speakers Bureau.