Inclusion Criteria

DISEASE CHARACTERISTICS: Diagnosis of chronic phase chronic myelogenous leukemia (CML)
Philadelphia (Ph) chromosome positive OR Bcr/Abl positive Refractory to or intolerant of
interferon alfa therapy Failure to achieve complete response for at least 1 month after at
least 6 months of interferon alfa therapy OR At least 65% Ph chromosome positivity in bone
marrow after at least 1 year of interferon alfa therapy OR At least 30% increase in Ph
chromosome positive bone marrow cells in samples taken at least 1 month apart or increase
to at least 65% while receiving interferon alfa therapy OR At least 100% increase in WBC
count to at least 20,000/mm3 in samples taken at least 2 weeks apart while receiving
interferon alfa therapy OR At least grade 3 nonhematologic toxicity persisting for more
than 2 weeks while receiving interferon alfa therapy (must be more than 3 months from time
of diagnosis) No greater than 15% blasts or basophils in peripheral blood or bone marrow
Less than 30% blasts plus promyelocytes in peripheral blood or bone marrow

PATIENT CHARACTERISTICS: Age: 18 and over Performance status: ECOG 0-3 Life expectancy:
Not specified Hematopoietic: Platelet count at least 100,000/mm3 Hepatic: Bilirubin no
greater than 2 times upper limit of normal (ULN) SGOT and SGPT no greater than 2 times ULN
Renal: Creatinine no greater than 2 times ULN Cardiovascular: No New York Heart
Association class III or IV heart disease Other: Not pregnant or nursing Negative
pregnancy test Fertile patients must use effective barrier contraception during and for at
least 2 weeks after study for women and at least 3 months after study for men No history
of noncompliance to prior medical regimens

PRIOR CONCURRENT THERAPY: Biologic therapy: See Disease Characteristics At least 14 days
since prior interferon alfa No other concurrent biologic therapy Chemotherapy: At least 6
weeks since prior busulfan At least 14 days since prior cytarabine At least 7 days since
prior hydroxyurea No other concurrent chemotherapy Endocrine therapy: Not specified
Radiotherapy: Not specified Surgery: Not specified Other: At least 28 days since prior
investigational agents No other concurrent investigational agents