High Dose (HD-AraC) Vs Standard Dose Cytosine Arabinoside (SDAraC) during Induction and Value of IL-2 during Maintenance in Acute Myelogenous Leukemia (AML): Impact of AraC Dose on Complete Remission Rate and Toxicity (Results on the first 1700 randomized patients of the AML-12 trial of EORTC and GIMEMA Leukemia Groups)
Authors: Willemze Roelof , Suciu Stefan , Mandelli Franco , Labar Boris , Marie Jean-Pierre , Mistrik Martin , Liso Vincenzo , Fabbiano Francesco , Nobile Francesco , Sborgia Marco , Rotoli Bruno , Selleslag Dominik L.D. , Lefrere Francois , Peta Antonio , Martelli Massimo F , Leone Giuseppe , Cantore Nicola , Beksac Meral , Berneman Zwi , Thomas Xavier , Greco Michele Mario , Bron Dominique , Fillet Georges , Guimaraes Jose E. , Muus Petra , Fazi Paola , Baila Liliana , Vignetti Marco , Amadori Sergio ,   Theo de Witte on behalfhe European Group for Blood Marrow Transplantation, Meloni Giovanna 
Published: April 2020

The AML-12 randomized phase III trial of EORTC-LG and GIMEMA assessed the efficacy and toxicity of HD-AraC (3 g/m2/12 hrs for 4 days) combined with daunorubicin (50 mg/sqm for 3 days) and etoposide (50 mg/sqm for 5 days) vs SD-AraC (100 mg/sqm for 10 days) with the same drugs. Patients (pts) in complete remission (CR) received 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 was performed after CR in pts without a donor: auto-SCT followed or not by low dose IL-2. The trial was powered to detect an 8% difference in the 5-yr survival rate; secondary endpoints were response to induction, DFS, toxicity. Randomization was performed centrally; the 1st randomization was stratified for age, performance status, WBC and center. Intent-to-treat analysis was done. From 9/1999 till 1/2008, 2005 previously untreated AML pts (APL excluded), age&lt;61 years, (891 by EORTCLG and 1114 by GIMEMA) were randomized. Currently for 1700 pts (857 in SD-AraC vs 843 in HD-AraC arm) sufficient information on remission induction response is available. The median follow up is 3 years. After 1 or 2 courses of induction, CR was achieved in 631 (73.6%) pts (SD-AraC group) vs 680 (80.7%) pts (HD-AraC group): p=0.001. Partial remission or resistance was documented in 161 (18.8%) vs 114 (13.5%) pts, and death in induction in 65 (7.6%) vs 49 (5.8%). Induction toxicity profile and grade was similar in the 2 arms except for conjunctivitis grade 3: 0.1% (SD-AraC) vs 4.4% (HD-AraC). Currently in 909 pts cytogenetic information is not yet available and in 791 pts cytogenetic information is known. Comparison of SD-AraC vs HD-AraC according to cytogenetic subgroups is shown in the Table.

No cytogenetics Good Intermediate Bad Very bad No pts 448 vs 461 55 vs 50 215 vs 200 89 vs 90 50 vs 42 CR (%) 71.2 vs 82.4 90.9 vs 84.0 78.6 vs 82.5 68.5 vs 77.8 64.0 vs 54.8 PR/Resistance (%) 20.3 vs 12.6 0 vs 6.0 15.3 vs 10.5 27.0 vs 16.7 26.0 vs 40.5 Induction death (%) 8.5 vs 5.0 9.1 vs 10.0 6.0 vs 7.0 4.5 vs 5.6 10.0 vs 4.8

In pts who reached CR, the DFS was similar in the 2 treatment groups: the 3-yr DFS rate was 43.4% (SD-Ara-C) vs 44.6% (HD-Ara-C), hazard ratio (HR)=0.96 (p=0.66). A total of 291 vs 313 DFS-events were reported in the 2 treatment groups: 230 (36.5%) vs 236 (34.7%) relapsed and 61 (9.7%) vs 77 (11.3%) died in CR. Among pts who reached CR, 451 pts had an HLA identical sibling and 860 did not or have not been typed. In the first group, 120/200 (60.0%) SD-AraC vs 134/251 (53.4%) HD-AraC pts underwent an allo-SCT. In the 2nd one, 211/431 (49.0%) SD AraC pts vs 211/429 (49.2%) HD AraC pts underwent an auto-SCT. In pts with a donor, the 3-yr DFS rate was 51.8% (SD-Ara-C) vs 47.6% (HD-Ara-C), HR=1.13, p=0.41, whereas in those without a donor the 3-yr DFS rate was 39.6% (SD-Ara-C) vs 42.9% (HD-Ara-C), HR=0.91, p=0.31. Evaluation of the first 1700 patients of the EORTC-GIMEMA AML-12 trial shows that, with a median follow-up of 3 years, HD-AraC in the induction treatment leads to a significantly higher CR rate than SD-Ara-C without improving the DFS.