Between 2000 and 2006, 85 adult BCR-ABL negative acute lymphoblastic leukaemia (ALL) patients between 18 and 60 years of age were treated using a modified paediatric regimen, which included high doses of asparaginase delivered weekly for 30 weeks during intensification. The complete response rate with induction therapy was 89%, and decreased with increasing age, mainly due to higher induction mortality. All post-induction treatments were delivered on an outpatient basis. The most common complications during intensification were infections (47%), osteonecrosis (32%), venous thromboembolism (23%) and neuropathy (22%). At a median follow-up of 4 years, the 5-year overall survival (OS) and relapse-free survival (RFS) were 63% and 71%, respectively. Significant adverse predictors for OS were age >35 years, high white blood cell count, MLL rearrangement, allogeneic stem cell transplantation in first complete remission and <80% of the planned asparaginase dose delivered during intensification. Patients aged < or = 35 years had a 3 year OS of 83%, as compared to 52% for patients aged >35 years. We conclude that the administration of this paediatric regimen is feasible and has considerable activity in adult ALL, particularly in younger patients. Effective delivery of asparaginase dosing appears to be important in achieving an optimal antileukaemic effect.