2. Patients should have failed (demonstrated resistance, intolerance or treatment discontinuation for any other reason of) at least 3 FDA-approved TKIs (other than bosutinib) if in CP (cohort 1), or at least 1 FDA-approved TKI (other than bosutinib) if in AP (cohort 2). Resistance will be defined as meeting the criteria for failure or warning by the European LeukemiaNet (ELN, Appendix)1. No prior therapy is necessary for patients in BP (cohort 2). Patients in CP who have failed <3 TKIs, but are ineligible to receive other FDA-approved TKIs, may also be enrolled in cohort 1. At least 10 CP patients with the T315I mutation affecting the kinase domain of Bcr-Abl will be enrolled in cohort 1, as well as in the phase II portion of cohort 2.