This study will evaluate the molecular response to high dose Gleevec in newly diagnosed patients with Chronic Myelogenous Leukemia (CML) in Chronic Phase. This study will evaluate the ability of Gleevec to reduce the amount of abnormal protein that occurs in patients with CML.

Patients who are eligible to participate will be treated for 18 months. This trial will include male or female patients 18 years or older who are newly diagnosed (within 6 months) with CML.

Inclusion Criteria:

Participants must meet all of the following criteria:

• Male or Female patients 18 years and older.
• Patient with a diagnosis of chronic myelogenous leukemia in chronic phase
• Within 6 months of initial diagnosis.
• Received any treatment for CML for less than 1 month prior to study entry with the exception of hydroxyurea and/or anagrelide.

Exclusion Criteria:

• Late chronic phase, accelerated phase or blastic phase
• Taking any other investigational agents within 28 days of starting the study
• If sibling donors have been identified and where allogeneic bone marrow transplantation will be the first line treatment.
• Another primary malignancy /cancer unless it is not considered clinically significant or does not require active intervention.
• If patients have heart problems or complications
• Pregnant or breast-feeding females
• Severe and/or uncontrolled disease such as diabetes, chronic renal disease, etc.
• Chronic liver disease (i.e., chronic active hepatitis, and cirrhosis).
• Diagnosis of human immunodeficiency virus (HIV) infection.
• Received any treatment for CML for longer than 1 month prior to study entry with the exception of hydroxyurea and/or anagrelide.
• Patient previously received radiotherapy to greater than 25% of the bone marrow.
• Patient had a major surgery within 4 weeks prior to study entry