ENFORCEA Multicenter, Open, Randomized, Controlled Phase IIb Trial Evaluating Efficacy and Tolerability of GRASPA (L-asparaginase Encapsulated in Red Blood Cells, Eryaspase) Plus Low-dose Cytarabine vs Low-dose Cytarabine Alone, in Treatment of Newly Diagnosed Acute Myeloid Leukemia (AML) Elderly Patients, Unfit for Intensive Chemotherapy

L-asparaginase (ASNase) holds a key role in chemotherapy for Acute Lymphoblastic Leukemia (ALL) in children and young adults. In elderly patients, its efficacy is counterbalanced by its toxicity, which impairs its use. However, a study conducted with GRASPA (L-asparaginase encapsulated in red blood cells, eryaspase) in elderly ALL (study reference "GRASPALL-GRAAL SA2 2008") showed that efficacy/safety profile was positive, paving the way for introducing ASNase benefit into chemotherapy for elderly patients. In adults, Capizzi (1988) reported a significant benefit of ASNase associated with high-dose cytarabine treatment (HiDAC) in Acute Myeloid Leukemia (AML). Indeed, there was an overall statistically superior complete remission rate for HiDAC/ASNase (40%) vs HiDAC (24%) and an overall survival benefit for patients treated with HiDAC/ASNase (19.6 weeks vs 15.9 weeks). Another study in elderly patients also displayed positive results for ASNase treatment (Petti, 1989), as well as recent single case reports that point out the potential benefit of ASNase in different AML or mixed lineage leukemia (Horikoshi, 2009; Rubnitz, 2009). Our preclinical results also showed that an AML cell line and blast cells from the bone marrow of AML patients were sensitive to ASNase in vitro. However, up to now, the toxicity of ASNase for elderly had prevented its use in this population that represents the majority of AML patients. Considering the promising results of ASNase for AML treatment and the better safety profile offered by GRASPA (L-aspariginase encapsulated in red blood cells, erysapase), a multicenter, randomized, controlled IIb trial is open for recruitment. Efficacy and tolerability of GRASPA plus low-dose cytarabine will be evaluated versus low-dose cytarabine alone in treatment of AML patients over 65 year-old, unfit for intensive chemotherapy. One hundred and twenty-three patients (65-85 year-old) newly diagnosed for AML are planned for inclusion in the study. A 2:1 randomization will be respected (82 patients treated with GRASPA® plus low-dose cytarabine and 41 patients treated with low-dose cytarabine alone). Each patient will be followed for 24 months.