Duration of MCyR while on bosutinib treatment. Duration of MCyR was based on the evaluable population; patients entering the study in cytogenetic remission (CCyR) were excluded. IM indicates imatinib; DAS, dasatinib; NI, nilotinib; and NA, not available. *Includes 2 patients: 1 patient who was nilotinib-intolerant and 1 who previously received all 3 inhibitors. †Probability of retaining response at 2 years was based on Kaplan-Meier estimates.