Key

Inclusion Criteria:

- Confirmed diagnosis of chronic phase Ph+ CML

- Previous first-line treatment with imatinib for a minimum of 2 years;

- Patient in complete cytogenetic response;

Key Exclusion Criteria:

- Previous achievement of MR4.0 at study entry;

- Previous treatment with other target cells inhibitors other than imatinib;

- Patients with any history of detectable atypical Leukemia transcripts or patients
with detectable atypical leukemia transcripts at screening;

- Previous anticancer agents for Chronic myeloid leukemia other than imatinib except
for cytoreduction;

- Severe and/or uncontrolled concurrent medical disease that in the opinion of the
investigator could cause unacceptable safety risks or compromise compliance with the
protocol;

- History of other active malignancies within the 5 years prior to study entry with the
exception of previous or concomitant basal cell skin cancer and previous carcinoma in
situ treated curatively;

- Patients who have not recovered from prior surgery;

- Treatment with other investigational agents within 4 weeks of Day 1;

- Impairment of gastrointestinal (GI) function or GI disease that may significantly
alter the absorption of study drug;