Survival advantage with imatinib mesylate therapy in chronic-phase chronic myelogenous ;eukemia (CML-CP) after IFN-alpha failure and in late CML-CP, comparison with historical controls.
OBJECTIVE
The purpose of this research was to compare the survival of patients with Philadelphia chromosome (Ph) -positive chronic myelogenous leukemia (CML) post-IFN-alpha failure treated with imatinib to historical experiences with standards of care or other therapies.


METHODS
The outcome of 261 patients with Ph-positive chronic phase CML post-IFN failure treated with imatinib was compared with 204 historical control patients treated for a similar disease status with existing therapies. A subset of 147 patients in late chronic phase CML and 100% Ph-positive status treated with imatinib was compared with 95 patients in a similar disease status treated with IFN. Multivariate analyses were conducted to assess the independent prognostic effect of therapy (imatinib versus other) on survival.


RESULTS
In the first analysis involving 261 patients on imatinib plus 204 historical patients, the complete cytogenetic response rates were 62% and 19%, respectively (P < 0.001). A multivariate analysis identified pretreatment peripheral blasts and thrombocytosis to be independent poor prognostic factors for survival. Imatinib therapy (versus others) was a significant independent favorable prognostic factor for survival (hazard ratio, 0.17; P < 0.0001). In the second analysis involving the subset of 147 patients receiving imatinib plus 95 historical patients treated with IFN regimens, the complete cytogenetic response rates were 41% and 7%, respectively (P < 0.001). A multivariate analysis selected pretreatment anemia and peripheral blasts to be significant independent poor prognostic factors for survival. Imatinib therapy (versus IFN) was an independent favorable prognostic factor for survival (hazard ratio, 0.20; P < 0.0001). Three-month and 6-month landmark analyses showed that patients in all cytogenetic response categories (major, minor, and none) after imatinib therapy had survival outcomes better than the historical control population. Within each cytogenetic response category, survival was also better with imatinib than with other therapies.


CONCLUSIONS
This analysis provides evidence for a survival advantage with imatinib versus other therapies in chronic-phase CML post-IFN failure, and for a survival advantage with imatinib versus IFN in late chronic-phase CML.
Kantarjian
Hagop
H
Department of Leukemia, University of Texas M.D. Anderson Cancer Center, Houston, Texas, USA. hkantarj@mdanderson.org
O'Brien
Susan
S
Cortes
Jorge
J
Giles
Francis
F
Shan
Jianqin
J
Rios
Mary Beth
MB
Faderl
Stefan
S
Verstovsek
Srdan
S
Garcia-Manero
Guillermo
G
Wierda
William
W
Kornblau
Steven
S
Ferrajoli
Alessandra
A
Keating
Michael
M
Talpaz
Moshe
M
D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001549:Benzamides; D016022:Case-Control Studies; D005500:Follow-Up Studies; D006801:Humans; D000068877:Imatinib Mesylate; D016898:Interferon-alpha / Q000627:therapeutic use*; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000188:drug therapy / Q000401:mortality*; D015466:Leukemia, Myeloid, Chronic-Phase / Q000188:drug therapy* / Q000401:mortality*; D008875:Middle Aged; D010879:Piperazines / Q000627:therapeutic use*; D011379:Prognosis; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D011743:Pyrimidines / Q000627:therapeutic use*; D016879:Salvage Therapy; D015996:Survival Rate; D017211:Treatment Failure; D016896:Treatment Outcome
D000970:Antineoplastic Agents; D001549:Benzamides; D016898:Interferon-alpha; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate; D011505:Protein-Tyrosine Kinases