RATIONALE: Imatinib mesylate may stop the growth of cancer cells by blocking the enzymes necessary for cancer cell growth. Oblimersen may help imatinib mesylate kill more cancer cells by making cancer cells more sensitive to the drug.

PURPOSE: Phase II trial to study the effectiveness of combining oblimersen with imatinib mesylate in treating patients who have chronic myelogenous leukemia that has not responded to previous treatment with imatinib mesylate.

OBJECTIVES:

• Determine the cytogenetic response rate of patients with imatinib mesylate-resistant chronic myelogenous leukemia treated with oblimersen and imatinib mesylate.
• Determine the hematologic and molecular response rate and duration of patients treated with this regimen.
• Determine the toxicity of this regimen in these patients.

OUTLINE: This is a multicenter study.

Patients receive oblimersen IV continuously on days 1-10 and oral imatinib mesylate once or twice daily. Treatment repeats every 21 days for up to 4 courses in the absence of disease progression or unacceptable toxicity. Patients without a hematologic response after 2 courses go off study. Patients with complete or partial response after 4 courses may continue to receive oral imatinib mesylate daily.

Patients in cohort 2 receive an escalated dose of oblimersen; if well tolerated, subsequent cohorts receive oblimersen at the higher dose with the original dose of imatinib mesylate. If oblimersen is not well tolerated in cohort 2, subsequent cohorts receive the original dose of oblimersen with an escalated dose of imatinib mesylate. The first 6 patients accrued continue to receive the original dose (dose taken prior to study) of imatinib mesylate throughout the study.

Patients are followed monthly for 3 months and then every 3 months for 5 years.

PROJECTED ACCRUAL: A total of 12-43 patients will be accrued for this study within 6 months.

• Biological: oblimersen sodium
• Drug: imatinib mesylate

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