查看文章

BCR-ABL, a constitutively activated tyrosine kinase, is the product of the Philadelphia (Ph) chromosome. This enzyme is present in virtually all cases of chronic myeloid leukemia (CML) throughout the course of the disease, and in 20 percent of cases of acute lymphoblastic leukemia (ALL). On the basis of the substantial activity of the inhibitor in patients in the chronic phase, we evaluated STI571 (formerly known as CGP 57148B), a specific inhibitor of the BCR-ABL tyrosine kinase, in patients who had CML in blast crisis and in patients with Ph-chromosome–positive ALL.

In this dose-escalating pilot study, 58 patients were treated with STI571; 38 patients had myeloid blast crisis and 20 had ALL or lymphoid blast crisis. Treatment was given orally at daily doses ranging from 300 to 1000 mg.

Responses occurred in 21 of 38 patients (55 percent) with a myeloid-blast-crisis phenotype; 4 of …