OBJECTIVES: I. Evaluate the safety profile of STI571 in patients with Philadelphia chromosome positive (or chromosome negative and Bcr/Abl positive) chronic phase chronic myelogenous leukemia who are refractory to or intolerant of interferon alfa. II. Provide expanded access of this treatment to these patients. III. Confirm the rate of complete and major cytogenetic response in patients treated with this regimen, as demonstrated by a decrease in the percentage of Philadelphia chromosome positive cells in the bone marrow. IV. Evaluate the improvement of symptomatic parameters in patients treated with this regimen.