Imatinib mesylate therapy improves survival in patients with newly diagnosed Philadelphia chromosome-positive chronic myelogenous leukemia in the chronic phase: comparison with historic data.

The International Randomized study of Interferon-alpha plus cytarabine (IFN-alpha plus ara-C) versus STI571 (imatinib mesylate) [IRIS trial] in patients with newly diagnosed Philadelphia chromosome (Ph)-positive, chronic-phase chronic myelogenous leukemia (CML) has not shown (to date) a survival advantage for imatinib. This was most likely because approximately 90% of patients receiving IFN-alpha plus ara-C changed to imatinib therapy after a median of 8 months into therapy. The authors analyzed the results with imatinib therapy in patients with newly diagnosed Ph-positive CML in chronic phase and compared their outcome with patients who received IFN-alpha regimens. A total of 187 patients with Ph-positive CML in early chronic phase treated with imatinib were compared with a historic group of 650 similar patients treated with IFN-alpha regimens from 1982 until 1997. Patients who received imatinib were significantly older and had significantly more bone marrow basophilia and less leukocytosis. The complete cytogenetic response (Ph 0%) rates were better with imatinib (81% vs. 32%; P < 0.001), as were the survival rates (30-month estimated survival rates 98% vs. 88%; P = 0.01). A multivariate analysis of the total study group of 837 patients identified imatinib therapy to be a significant independent favorable prognostic factor for survival (P = 0.01). The current study is the first to indicate the survival advantage of imatinib compared with IFN-alpha, the previous standard of care, in patients with early chronic-phase CML.

Kantarjian HM ，O'Brien S ，Cortes J ，Giles FJ ，Rios MB ，Shan J ，Faderl S ，Garcia-Manero G ，Ferrajoli A ，Verstovsek S ，Wierda W ，Keating M ，Talpaz M ... -  《CANCER》

Analysis of the impact of imatinib mesylate therapy on the prognosis of patients with Philadelphia chromosome-positive chronic myelogenous leukemia treated with interferon-alpha regimens for early chronic phase.

The effect on prognosis of adding imatinib mesylate to the treatment of patients with Philadelphia chromosome (Ph)-positive chronic myelogenous leukemia (CML) has not been explored fully. The objective of the current study was to evaluate the benefit of adding imatinib to the treatment sequence of patients with early chronic phase Ph-positive CML who received interferon alpha (IFN)-based regimens as frontline therapy. A total of 201 patients with early chronic phase Ph-positive CML who were treated on our 3 recent frontline IFN-based programs and were impacted early by the availability of sequential therapy with imatinib were analyzed. Their outcome was compared with that of a historical control group of 293 patients treated from 1982 until 1990 who were treated with IFN programs for early chronic phase CML and who did not have the opportunity of early access to imatinib (because it was not available during that period). Multivariate analysis was used to evaluate the independent effect of imatinib therapy on survival. Of 201 patients who were treated, 159 patients (79%) had their regimen changed sequentially to imatinib after a median duration of 14 months of IFN therapy. Of 139 patients who continued evaluation at our institution, 101 patients (73%; 64% of the total group) achieved a complete cytogenetic response, and 20 of 80 patients analyzed (25%; 10% of the total group) had no disease according to molecular studies (quantitative polymerase chain reaction studies). The estimated 5-year survival rate for the total study group of 201 patients was 86%. Survival of this group was significantly superior to the historic control group of IFN-treated patients who did not have the benefit of imatinib (P = 0.03). The trend also was observed within defined CML risk groups. Imatinib therapy was confirmed as an independent, significant, favorable prognostic factor for survival by multivariate analysis, after accounting for the independent prognostic effect of pretreatment prognostic factors (P = 0.005). The current analysis is the first to indicate the independent, favorable effect of imatinib on the survival of patients with Ph-positive CML.

Kantarjian H ，O'Brien S ，Cortes J ，Shan J ，Giles F ，Garcia-Manero G ，Verstovsek S ，Faderl S ，Rios MB ，Talpaz M ... -  《CANCER》

Effects of age on prognosis with imatinib mesylate therapy for patients with Philadelphia chromosome-positive chronic myelogenous leukemia.

Older age is a consistent poor prognostic factor in patients with Philadelphia chromosome (Ph)-positive chronic myelogenous leukemia (CML). Whether this is related to an intrinsic worse disease biology or to inadequate drug delivery or excessive treatment-associated toxicity is unknown. The availability of imatinib mesylate, a selective, Bcr-Abl-targeted therapy that is administered orally with minimal side effects, may clarify whether older age would remain an adverse factor (thus, implying a different age-related CML biology). Seven hundred forty-seven patients in different phases of Ph-positive CML who were treated with imatinib from 1999 until the time of last follow-up were evaluated. Among them, 187 patients had newly diagnosed, early chronic phase CML; 351 patients had chronic phase CML after interferon alpha (IFN) failure; 133 patients had accelerated phase CML; and 76 patients had blastic phase CML. The imatinib daily dose varied from 400 mg to 800 mg orally, according to the protocol design. Patients were categorized into a group of older patients (age 60 years or older) or younger patients (age younger than 60 years). Their characteristics, responses to therapy, and survival were compared by univariate and multivariate analyses. One hundred eighty-seven patients had newly diagnosed CML, and 49 patients (26%) were in the older age group. Older patients had similar cytogenetic response rates and survival compared with younger patients. Among 351 patients with late chronic phase CML after IFN failure, 120 patients (34%) were in the older age group. Although the older patients had a lower incidence of achievement of complete cytogenetic response (Ph, 0%) by univariate analysis (56% vs. 44%; P = 0.05), age was not found to be an independent poor prognostic factor in the multivariate analysis. Similarly, older age was not an adverse poor prognostic factor for survival. Forty-two of 133 patients (32%) with accelerated phase CML were older. The incidence of any cytogenetic response was lower in older patients (53% vs. 33%; P = 0.04), but age was not significant in the multivariate analysis. Older patients also had a trend toward worse survival (P = 0.09) that was not significant in the multivariate analysis. Twenty-eight of 76 patients (37%) evaluated in blastic phase were older. Older age was not a significant prognostic factor either for achieving response or for survival. With imatinib therapy, older age appears to have lost much of its prognostic relevance. This suggests that the previous poor prognosis observed with older age was related to treatment-associated factors (e.g., toxicity with allogeneic transplantation or with IFN therapy) rather than to an intrinsic, different disease biology of CML in older patients.

Cortes J ，Talpaz M ，O'Brien S ，Giles F ，Beth Rios M ，Shan J ，Faderl S ，Garcia-Manero G ，Ferrajoli A ，Wierda W ，Kantarjian H ... -  《CANCER》

Imatinib mesylate for Philadelphia chromosome-positive, chronic-phase myeloid leukemia after failure of interferon-alpha: follow-up results.

Kantarjian HM ，Talpaz M ，O'Brien S ，Smith TL ，Giles FJ ，Faderl S ，Thomas DA ，Garcia-Manero G ，Issa JP ，Andreeff M ，Kornblau SM ，Koller C ，Beran M ，Keating M ，Rios MB ，Shan J ，Resta D ，Capdeville R ，Hayes K ，Albitar M ，Freireich EJ ，Cortes JE ... -  《CLINICAL CANCER RESEARCH》

Results of triple therapy with interferon-alpha, cytarabine, and homoharringtonine, and the impact of adding imatinib to the treatment sequence in patients with Philadelphia chromosome-positive chronic myelogenous leukemia in early chronic phase.

Before the discovery of imatinib mesylate, a Bcr-Abl selective tyrosine kinase inhibitor, three agents, interferon-alpha (IFN-alpha), cytarabine (ara-C), and homoharringtonine (HHT), had demonstrated activity against Philadelphia chromosome (Ph)-positive chronic myelogenous leukemia (CML) as single agents and in couplet combinations. The goals of the current study were to evaluate the efficacy of the triple combination regimen with IFN-alpha, ara-C, and HHT in newly diagnosed Ph-positive CML and to assess the impact of the added sequential therapy with imatinib on overall prognosis. Ninety patients with Ph-positive CML in early chronic phase received the triple regimen. Therapy consisted of 5 million units (MU)/m(2) IFN-alpha subcutaneously (s.c. daily, ara-C 10 mg s.c. daily, and HHT 2.5 mg/m(2) by continuous infusion over 24 hours daily x 5 every month. After a median duration of 16.5 months of therapy, 78 patients had their therapy changed to 400 mg orally administered imatinib daily. With the triple regimen, 85 patients (94%) achieved complete hematologic response and 67 patients (74%) had a cytogenetic response (Ph suppression to < or = 90%) which was complete (Ph 0%) in 20 patients (22%) and major in 42 patients (46%). Myelosuppression was significant, resulting in considerable reductions in the dose schedules. After 12 months of therapy, the median IFN-alpha dose was 1.6 MU/m(2) daily, the median ara-C dose was 1.85 mg daily, and the median number of HHT days was 2 every month. Only three patients developed blastic phase while receiving the triple regimen. With the change to imatinib therapy, currently 57 patients (63%) are in complete cytogenetic response and 69 patients (76%) in major cytogenetic response. With a median follow-up time of 46 months for the total study group, the estimated 5-year survival rate was 88%, and only 8 patients (9%) to date have developed blastic phase. The sequence of IFN-alpha, ara-C, and HHT followed by imatinib (imposed by the discovery of the latter drug) resulted in an estimated 5-year survival rate of 88%. This finding suggests that imatinib combination regimens may improve the prognosis in CML.

O'Brien S ，Giles F ，Talpaz M ，Cortes J ，Rios MB ，Shan J ，Thomas D ，Andreeff M ，Kornblau S ，Faderl S ，Garcia-Manero G ，White K ，Mallard S ，Freireich E ，Kantarjian HM ... -  《CANCER》