One hundred and forty-seven patients aged < 55 years with advanced acute lymphoblastic leukaemia (ALL) were enrolled in an Italian cooperative study (ALL R-87). This protocol consists of an induction phase with idarubicin (IDA) plus intermediate-dose cytarabine (IDARA-C), followed by a consolidation phase and bone marrow transplant (BMT). Complete remission (CR) was achieved in 97/147 patients (66%) with a CR rate of 77% in children versus 51% in adults (P < 0.01). 48 responders (50%) underwent BMT. Probability of event-free survival (EFS +/- SE) was 10.2 +/- 3.1% at 56 months. EFS was 14.3 +/- 4.51% at 56 months for children versus 3.8 +/- 3.41% at 37 months for adults (P < 0.0001). Among patients treated in first relapse, EFS was 14.2 +/-7.79% for patients with CR > 18 months verus 6.6 +/- 3.17% for those with CR < 18 months (P < 0.0001). Projected disease-free survival (DFS +/- SE) was 15.4 +/- 4.61% at 55 months for all responders and 43.3 +/- 14.34% at 52 months for allografted patients. Projected overall probability of survival +/- SE for all patients was 18.8 +/- 4.13% at 56 months. This study confirms the efficacy of IDA plus IDARA-C in poor-risk. ALL patients. A more intensive post-remission therapy or alternative approach must be designed to improve long-term results.