A trial of de-escalation and stopping treatment in chronic myeloid leukaemia patients with excellent responses to tyrosine kinase inhibitor therapy DESTINY(De- Escalation and Stopping Treatment of Imatinib, Nilotinib or sprYcel in chronic myeloid leukaemi

The primary endpoint of the study is the proportion of patients who lose MMR during the trial observation period of 37 months. BCR-ABL1 will be assessed by standard PCR based molecular monitoring on blood. This is a routine part of clinical follow-up, but will be carried out more frequently than usual. It is not expected that any patient will undergo more serious relapse than loss of MMR, so there are no formal plans for routine marrow examinations. MR4 and MMR patients will receive the same strategy, but will be analysed separately.