Activity of a specific inhibitor of the BCR-ABL tyrosine kinase in the blast crisis of chronic myeloid leukemia and acute lymphoblastic leukemia with the Philadelphia chromosome.
BACKGROUND
BCR-ABL, a constitutively activated tyrosine kinase, is the product of the Philadelphia 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 ALL who had the Ph chromosome.


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


RESULTS
Responses occurred in 21 of 38 patients (55 percent) with a myeloid-blast-crisis phenotype; 4 of these 21 patients had a complete hematologic response. Of 20 patients with a lymphoid blast crisis or ALL, 14 (70 percent) had a response, including 4 who had complete responses. Seven patients with a myeloid blast crisis continue to receive treatment and remain in remission from 101 to 349 days after starting the treatment. All but one patient with a lymphoid blast crisis or ALL has relapsed. The most frequent adverse effects were nausea, vomiting, edema, thrombocytopenia, and neutropenia.


CONCLUSIONS
The BCR-ABL tyrosine kinase inhibitor STI571 is well tolerated and has substantial activity in the blast crises of CML and in Ph-positive ALL.
Druker
B J
BJ
Division of Hematology and Medical Oncology, Oregon Health Sciences University, Portland 97201, USA. drukerb@ohsu.edu
Sawyers
C L
CL
Kantarjian
H
H
Resta
D J
DJ
Reese
S F
SF
Ford
J M
JM
Capdeville
R
R
Talpaz
M
M
D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000009:adverse effects; D001549:Benzamides; D001752:Blast Crisis / Q000097:blood / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology; D001772:Blood Cell Count; D018572:Disease-Free Survival; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D016044:Fusion Proteins, bcr-abl / Q000037:antagonists & inhibitors* / Q000378:metabolism; D006801:Humans; D000068877:Imatinib Mesylate; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000097:blood / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010677:Philadelphia Chromosome; D010865:Pilot Projects; D010879:Piperazines / Q000008:administration & dosage* / Q000009:adverse effects; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000097:blood / Q000188:drug therapy* / Q000201:enzymology / Q000235:genetics; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors*; D011743:Pyrimidines / Q000008:administration & dosage* / Q000009:adverse effects; D012008:Recurrence; D012074:Remission Induction / Q000379:methods
D000970:Antineoplastic Agents; D001549:Benzamides; D004791:Enzyme Inhibitors; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate; D011505:Protein-Tyrosine Kinases; D016044:Fusion Proteins, bcr-abl