A randomized trial for adults with newly diagnosed acute lymphoblastic leukaemia. Multisite, randomised controlled trial, recruiting 811 patients over 7.5 years. Samples will be collected throughout the trial and sent to the central lab (Adult ALL MRD Lab @ UCL CI) as follows;

• bone marrow samples taken at diagnosis, at recover post phase 1 and phase 2, post transplant (for those patients who proceed with a non-myeloablative transplant) and at relapse.
• peripheral blood sample taken during phase 1 on days 4 & 18 (in patients 40 and under) and on D18 & 32 in patients 41 or over), and during intensification. Additionally for those patients who proceed for a non-myeloablative transplant peripheral blood will be sent to the local chimerism labs and a copy of the report will be sent to UCL CTC.