DISEASE CHARACTERISTICS: Cytologically proven chronic phase chronic myelogenous leukemia Philadelphia chromosome detectable by cytogenetic studies OR 1 of the following: BCR/ABL protein detectable by immunoblotting BCR/ABL rearrangement detectable by Southern blot analysis Polymerase chain reaction positive fusion transcripts for BCR/ABL BCR/ABL translocation present by fluorescence in situ hybridization No prior intolerance or failure to respond to hydroxyurea Must have failed adequate trial (5M units/m2/day) of interferon alfa (IFN) or the combination of IFN and cytarabine as defined by 1 of the following: Failure to achieve complete hematologic response after 6 months of IFN Failure to achieve any cytogenetic response (i.e., still 100% Philadelphia chromosome positive) after 12 months of IFN Intolerable adverse effects of IFN after at least 1 month of IFN Significant documented toxicity of grade 3 or greater due to IFN required Loss of a prior hematologic remission or cytogenetic response to IFN Two-fold increase in WBC count compared to WBC count when IFN initiated

PATIENT CHARACTERISTICS: Age: 16 and over Performance status: Not specified Life expectancy: Not specified Hematopoietic: See Disease Characteristics Hepatic: Not specified Renal: Not specified Cardiovascular: No uncontrolled tachyarrhythmias (e.g., atrial fibrillation, paroxysmal superventricular tachycardia, or ventricular tachycardias not adequately controlled) Other: Not pregnant or nursing Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY: Biologic therapy: At least 7 days since prior interferon alfa Chemotherapy: See Disease Characteristics No prior homoharringtonine Less than 180 days cumulative prior hydroxyurea No more than 60 days hydroxyurea after failing interferon Endocrine therapy: No concurrent hormones except for nondisease related conditions (e.g., insulin for diabetes, estrogen for osteopenia) Concurrent steroids for adrenal failure allowed Radiotherapy: No concurrent palliative radiotherapy Surgery: No concurrent splenectomy except for emergency management