DISEASE CHARACTERISTICS:

• Diagnosis of chronic myelogenous leukemia in chronic phase

• Refractory to prior imatinib mesylate by the following criteria:

  • At least 400 mg/day for more than 8 weeks without a complete hematologic response or more than 6 months without a major cytogenetic response
  • No evidence of disease progression to accelerated or blast phases
• Must have received stable dose (at least 600 mg/day) of imatinib mesylate for at least 4 weeks without grade 2 or greater toxic effects

• If Philadelphia chromosome t(9;22) or a variant translocation is not detectable, then patients must meet 1 of the following:

  • Polymerase chain reaction positive fusion transcripts for BCR/ABL
  • BCR/ABL translocation present by fluorescence in situ hybridization
• Must also be registered on CLB-9665 and CLB-29801

PATIENT CHARACTERISTICS:

Age

• 15 and over

Performance status

• Not specified

Life expectancy

• At least 2 years

Hematopoietic

• Not specified

Hepatic

• Bilirubin no greater than 2 mg/dL
• AST no greater than 1.5 times upper limit of normal (ULN)
• PTT no greater than 1.5 times ULN

Renal

• Creatinine no greater than 2 mg/dL

Cardiovascular

• No uncontrolled cardiovascular disease

Pulmonary

• No pulmonary disease that would preclude study participation

Other

• No other concurrently active malignancy except nonmelanoma skin cancer (i.e., completed therapy and considered to be at less than 30% risk of relapse within 1 year)
• No diabetes
• No infection
• No other serious illness that would limit life expectancy
• No psychiatric condition that would preclude study participation
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective barrier contraception during and for at least 3 months after study participation

PRIOR CONCURRENT THERAPY:

Biologic therapy

• No prior stem cell transplantation
• At least 4 weeks since prior interferon

Chemotherapy

• At least 4 weeks since prior hydroxyurea, homoharringtonine, or cytarabine
• No other prior antineoplastic agents (e.g., busulfan)
• No concurrent chemotherapy

Endocrine therapy

• No concurrent hormones except for steroids for adrenal failure or drug-related rash or hormones for nondisease-related conditions (e.g., insulin for diabetes or estrogens for osteopenia)

Radiotherapy

• No concurrent palliative radiotherapy

Surgery

• No concurrent surgical splenectomy except for traumatic injury, unresponsive infarction, emergency management, or splenic hemorrhage

Other

• At least 4 weeks since prior investigational agents
• At least 4 weeks since prior anagrelide
• No concurrent oral anticoagulants