• Primary Outcomes: The primary objective of this study was to assess the ability of lomustine to increase the CR rate and to improve overall survival [ Time Frame: 13 months ]
  

• Secondary Outcomes: The secondary objective was to test intermediate-dose cytarabine on survival, and to analyze the impact of prognostic factors on CR and survival. [ Time Frame: 13 months ]
  

Induction therapy: Patients were randomized to receive idarubicin plus cytarabine (IC) or the same drugs plus lomustine (ICL), the latter given at the dose of 200 mg/m2 orally at day 1. Patients with persistent leukemia in the bone marrow, defined by at least 20% marrow cellularity with more than 5% blasts on day 14 or at a subsequent time point following initiation of induction therapy, received a second course of induction chemotherapy identical to the initial induction course. Non-responders to the second induction course were taken off the protocol.

Consolidation therapy: After completing induction treatment, patients who were in complete remission after 1 or 2 induction courses received a course of consolidation (IC’) therapy with idarubicin and subcutaneous cytarabine. Subsequently, if stable remission persisted, the patients received maintenance therapy or maintenance therapy preceded by a second consolidation (IIC) with intermediate-dose cytarabine. Randomization was performed as soon as CR was achieved.

Maintenance therapy: This was conducted in all patients with persisting CR one month after completing the first (IC) or second (IIC) consolidation and consisted of the following: five courses of combination chemotherapy at 1, 3, 6, 9 and 13 months from the last consolidation, namely cytarabine (subcutaneously) and idarubicin and between these courses for one year: a continuous regimen of methotrexate and 6-mercaptopurine, as alternating 10 day-courses .