Chronic myeloid leukaemia (CML) is a myeloproliferative disease characterised by a chromosomal translocation fusing the ABL1 and BCR genes, resulting in production of the BCR—ABL oncoprotein, a constitutively active tyrosine kinase. A decade ago, the introduction of imatinib—a tyrosine kinase inhibitor (TKI)—was a key advance in molecularly targeted therapy of cancer. Imatinib greatly improved the outcome of patients with chronic-phase CML, with event-free survival greater than 80% after 6 years....