Biomedical subjects

Francis Giles

Publications and source records attributed to Francis Giles.

At least 19 recordsLinked to original sources

PubMed2007

Phase I/II study of subcutaneous homoharringtonine in patients with chronic myeloid leukemia who have failed prior therapy.

BACKGROUND: Homoharringtonine (HHT) is a cephalotaxus alkaloid that inhibits the synthesis of proteins leading to apoptosis. Intravenous HHT has demonstrated activity in patients with chronic myeloid leukemia (CML) after failure with interferon. METHODS: A Phase I study was completed of subcutaneous (s.c.) HHT in patients with CML in accelerated or blast phases and demonstrated efficacy and good tolerance at the same doses used by intravenous (i.v.) administration. The maximal tolerated dose (MTD) was 1.25 mg/m(2) s.c. twice daily. The cohort was then expanded to treated at the MTD to include patients in late chronic phase CML after imatinib failure. Therapy consisted of an i.v. loading dose of HHT 2.5 mg/m(2) over 24 hours, followed by 1.25 mg/m(2) s.c. twice daily for 14 days every 28 days until remission, then for 7 days every 28 days. Six patients (median age, 53 years) who had failed imatinib were treated and 5 were evaluable. Patients received a median of 4.5 courses of s.c. HHT. RESULTS: Complete hematologic remission was obtained in all 5 evaluable patients and 3 had cytogenetic (CG) responses: 1 complete and 2 minor. The 2 patients with BCR-ABL kinase domain mutations at the start of therapy with HHT had a CG response and in both instances the mutations became undetectable. All patients developed myelosuppression and 3 had their HHT dose reduced due to prolonged neutropenia. Nonhematologic toxicity was mild and manageable. CONCLUSIONS: Subcutaneous HHT is well tolerated and may have clinical activity in patients with CML after imatinib failure.

Adult↗

PubMed2006

New insights into the pathophysiology of chronic myeloid leukemia and imatinib resistance.

Chronic myeloid leukemia (CML) was the first human malignant disease to be linked to a single, acquired genetic abnormality. Identification of the BCR-ABL kinase fusion protein and its central role in the pathogenesis of CML provided new opportunities to develop rational molecular targeted therapies. This review provides an update on the underlying pathophysiologies of disease progression and imatinib mesylate resistance, leading to the development of new targeted tyrosine kinase inhibitors for managing CML. Imatinib, a selective inhibitor of BCR-ABL, represents a major success in the era of target-directed cancer chemotherapy. However, patients with advanced CML have been less sensitive to therapy and responses have been short. In addition, treatment resistance is an emerging problem at all disease stages. Insight into factors involved in imatinib resistance and disease progression has highlighted a role for such BCR-ABL-dependent factors as amplification and overexpression of the BCR-ABL gene and the emergence of mutant isoforms of BCR-ABL. However, BCR-ABL-independent factors, including leukemogenic pathways involving kinases other than BCR-ABL, also play a part. In light of the limitations of imatinib against these factors, newer tyrosine kinase inhibitors, including dasatinib (a multitargeted kinase inhibitor of BCR-ABL and Src family kinases) and nilotinib (AMN107, a selective BCR-ABL inhibitor), may provide promising treatment options for patients with CML.

Antineoplastic Agents↗

PubMed2006

Cloretazine (VNP40101M), a novel sulfonylhydrazine alkylating agent, in patients age 60 years or older with previously untreated acute myeloid leukemia.

PURPOSE: Cloretazine (VNP40101M) is a sulfonylhydrazine alkylating agent with significant antileukemia activity. A multicenter phase II study of cloretazine was conducted in patients 60 years of age or older with previously untreated acute myeloid leukemia (AML) or high-risk myelodysplastic syndrome (MDS). PATIENTS AND METHODS: Cloretazine 600 mg/m2 was administered as a single intravenous infusion. Patients were stratified by age, performance score, cytogenetic risk category, type of AML, and comorbidity. RESULTS: One hundred four patients, median age 72 years (range, 60 to 84 years), were treated on study. Performance status was 2 in 31 patients (30%) and no patient had a favorable karyotype. Forty-seven patients (45%) had cardiac disease, 25 patients (24%) had hepatic disease, and 19 patients (18%) had pulmonary disease, defined as per the Hematopoietic Cell Transplantation-Specific Comorbidity Index, at study entry. The overall response rate was 32%, with 29 patients (28%) achieving complete response (CR) and four patients (4%) achieving CR with incomplete platelet recovery. Response rates in 44 de novo AML patients, 45 secondary AML patients, and 15 high-risk MDS patients were 50%, 11%, and 40%, respectively. Response by cytogenetic risk category was 39% in 56 patients with intermediate cytogenetic risk and 24% in 46 patients with unfavorable cytogenetic risk. Nineteen (18%) patients died within 30 days of receiving cloretazine therapy. Median overall survival was 94 days, with a 1-year survival of 14%; the median duration of survival was 147 days, with a 1-year survival of 28% for those who achieved CR. CONCLUSION: Cloretazine has significant activity and modest extramedullary toxicity in elderly patients with AML or high-risk MDS. Response rates remain consistent despite increasing age and comorbidity.

Aged↗

PubMed2006

Activity of 9-nitro-camptothecin, an oral topoisomerase I inhibitor, in myelodysplastic syndrome and chronic myelomonocytic leukemia.

BACKGROUND: Topoisomerase I inhibitors, like topotecan, have activity in myelodysplastic syndrome (MDS) and chronic myelomonocytic leukemia (CMML). 9-Nitro-camptothecin (9-NC) is a new oral topoisomerase inhibitor with a good safety profile. The aims of the current study were to evaluate the activity and safety of 9-NC in MDS and CMML. METHODS: Adults with a diagnosis of MDS (n = 12) and CMML (n = 32) received 9-NC 2 mg/m(2) orally daily 5 days a week, every 4 to 6 weeks. RESULTS: Overall, 5 (11%) patients achieved complete response (CR), 7 (16%) had a partial response (PR), and 6 (14%) had hematologic improvement (HI), for an overall response rate of 41%. The response rate was similar in MDS and CMML. Severe (Grade 3-4) side effects included nausea and vomiting (7%), diarrhea (18%), other gastrointestinal toxicities (5%), and genitourinary toxicities (12%). CONCLUSIONS: 9-NC is active in MDS and CMML. The paucity of available therapies in CMML makes 9-NC a good candidate for further studies as a single agent, or in combination with decitabine, 5-azacitidine or cytarabine.

Administration, Oral↗

PubMed2006

Dasatinib (BMS-354825) is active in Philadelphia chromosome-positive chronic myelogenous leukemia after imatinib and nilotinib (AMN107) therapy failure.

Developing strategies to counteract imatinib resistance constitutes a challenge in chronic myelogenous leukemia (CML). Therapy with the tyrosine kinase inhibitors nilotinib (AMN107) and dasatinib (BMS-354825) has produced high rates of hematologic and cytogenetic response. Src kinase activation has been linked to Bcr-Abl-mediated leukemogenesis and CML progression. In addition to binding Abl kinase with less stringent conformational requirements than imatinib, dasatinib is a potent Src kinase inhibitor. In the current study, we report on 23 patients with CML (19 of them in accelerated or blastic phases) treated with dasatinib after treatment failure with both imatinib and nilotinib. More than half (13; 57%) of 23 patients responded to dasatinib: 10 (43%) had a complete hematologic response (CHR), including 7 (30%) who had a cytogenetic response (2 complete, 4 partial, and 1 minor). These results suggest that dasatinib may be active in some patients after failure with both imatinib and nilotinib.

Adult↗

PubMed2006

A phase I study of intravenous LBH589, a novel cinnamic hydroxamic acid analogue histone deacetylase inhibitor, in patients with refractory hematologic malignancies.

PURPOSE: LBH589 is a novel histone deacetylase inhibitor that inhibits proliferation and induces apoptosis in tumor cell lines. In this phase I study, LBH589 was administered i.v. as a 30-minute infusion on days 1 to 7 of a 21-day cycle. EXPERIMENTAL DESIGN: Fifteen patients (median age, 63 years; range, 42-87 years) with acute myeloid leukemia (13 patients), acute lymphocytic leukemia (1 patient), or myelodysplastic syndrome (1 patient) were treated with LBH589 at the following dose levels (mg/m(2)): 4.8 (3 patients), 7.2 (3 patients), 9.0 (1 patient), 11.5 (3 patient), and 14.0 (5 patients). The levels of histone acetylation were measured using quantitative flow cytometry and plasma LBH589 concentrations were assayed. RESULTS: Four dose-limiting toxicities (grade 3 QTcF prolongation) were observed, four at 14.0 mg/m(2) and one at 11.5 mg/m(2). QTcF prolongation was asymptomatic and reversed on LBH589 discontinuation. Other potentially LBH589-related toxicities included nausea (40%), diarrhea (33%), vomiting (33%), hypokalemia (27%), loss of appetite (13%), and thrombocytopenia (13%). In 8 of 11 patients with peripheral blasts, transient reductions occurred with a rebound following the 7-day treatment period. H3 acetylation increase was significant in B-cells (CD19(+); P = 0.02) and blasts (CD34(+); P = 0.04). The increase in H2B acetylation was highest in CD19(+) and CD34(+) cells [3.8-fold (P = 0.01) and 4.4-fold (P = 0.03), respectively]. The median acetylation of histones H2B and H3 in CD34(+) and CD19(+) cells significantly increased on therapy as did apoptosis in CD14(+) cells. Area under the curve increased proportionally with dose with a terminal half-life of approximately 11 hours. CONCLUSION: Intravenous administration of LBH589 was well tolerated at doses <11.5 mg/m(2) with consistent transient antileukemic and biological effects.

Acute Disease↗

PubMed2006

Results of a randomized study of 3 schedules of low-dose decitabine in higher-risk myelodysplastic syndrome and chronic myelomonocytic leukemia.

Epigenetic therapy with hypomethylating drugs is now the standard of care in myelodysplastic syndrome (MDS). Response rates remain low, and mechanism-based dose optimization has not been reported. We investigated the clinical and pharmacodynamic results of different dose schedules of decitabine. Adults with advanced MDS or chronic myelomonocytic leukemia (CMML) were randomized to 1 of 3 decitabine schedules: (1) 20 mg/m2 intravenously daily for 5 days; (2) 20 mg/m2 subcutaneously daily for 5 days; and (3) 10 mg/m2 intravenously daily for 10 days. Randomization followed a Bayesian adaptive design. Ninety-five patients were treated (77 with MDS, and 18 with CMML). Overall, 32 patients (34%) achieved a complete response (CR), and 69 (73%) had an objective response by the new modified International Working Group criteria. The 5-day intravenous schedule, which had the highest dose-intensity, was selected as optimal; the CR rate in that arm was 39%, compared with 21% in the 5-day subcutaneous arm and 24% in the 10-day intravenous arm (P < .05). The high dose-intensity arm was also superior at inducing hypomethylation at day 5 and at activating P15 expression at days 12 or 28 after therapy. We conclude that a low-dose, dose-intensity schedule of decitabine optimizes epigenetic modulation and clinical responses in MDS.

Aged↗

PubMed2006

Adaphostin has significant and selective activity against chronic and acute myeloid leukemia cells.

Adaphostin is a tyrphostin that was designed to inhibit Bcr/Abl tyrosine kinase by altering the binding site of peptide substrates rather than that of adenosine triphosphate, a known mechanism of imatinib mesylate (IM). However, it has been shown that adaphostin-mediated cytotoxicity is dependent on oxidant production and does not require Bcr/Abl. We have tested adaphostin against both Philadelphia chromosome (Ph)-positive (K562, KBM5, KBM5-R [IM resistant KBM5], KBM7, and KBM7-R [IM-resistant KBM7]) and Ph-negative (OCI/AML2 and OCI/AML3) cells, and against cells from patients with chronic myeloid leukemia (CML) and acute myeloid leukemia (AML). Adaphostin significantly inhibited growth of all cell lines (50% inhibition of cell proliferation [IC50] 0.5-1 microM) except K562 (IC50 13 microM). Ph-positive IM-resistant cell lines showed significant cross resistance to adaphostin. Simultaneous or sequential treatment with adaphostin and IM did not exert a synergistic effect in any KBM line. Adaphostin induced superoxide and apoptosis in a dose-dependent and time-dependent fashion in both Ph-positive and Ph-negative cells. Adaphostin selectively inhibited colony growth of cells from CML (IM-sensitive and IM-resistant) and AML patients. Analysis of tyrosine phosphorylated proteins after treatment with adaphostin revealed alternate effects in different cells consistent with the modulation of multiple targets. In conclusion, adaphostin showed significant and selective activity against CML and AML cells and its development for clinical testing is warranted.

Adamantane↗

PubMed2006

Nilotinib in imatinib-resistant CML and Philadelphia chromosome-positive ALL.

BACKGROUND: Resistance to imatinib mesylate can occur in chronic myelogenous leukemia (CML). Preclinical in vitro studies have shown that nilotinib (AMN107), a new BCR-ABL tyrosine kinase inhibitor, is more potent than imatinib against CML cells by a factor of 20 to 50. METHODS: In a phase 1 dose-escalation study, we assigned 119 patients with imatinib-resistant CML or acute lymphoblastic leukemia (ALL) to receive nilotinib orally at doses of 50 mg, 100 mg, 200 mg, 400 mg, 600 mg, 800 mg, and 1200 mg once daily and at 400 mg and 600 mg twice daily. RESULTS: Common adverse events were myelosuppression, transient indirect hyperbilirubinemia, and rashes. Of 33 patients with the blastic phase of disease, 13 had a hematologic response and 9 had a cytogenetic response; of 46 patients with the accelerated phase, 33 had a hematologic response and 22 had a cytogenetic response; 11 of 12 patients with the chronic phase had a complete hematologic remission. CONCLUSIONS: Nilotinib has a relatively favorable safety profile and is active in imatinib-resistant CML. (ClinicalTrials.gov number, NCT00109707 [ClinicalTrials.gov].).

Adolescent↗

PubMed2006

A Phase II study of Bcl-2 antisense (oblimersen sodium) combined with gemtuzumab ozogamicin in older patients with acute myeloid leukemia in first relapse.

Oblimersen selectively targets Bcl-2 mRNA and has been shown to enhance the apoptotic activity of various antileukemic agents, including gemtuzumab ozogamicin (GO), in preclinical studies. We evaluated the efficacy and safety of oblimersen combined with GO in patients > or =60 years of age in first relapse with CD33+ acute myeloid leukemia. Oblimersen 7 mg/kg/day was given as a continuous intravenous infusion on days 1-7 and 15-21. GO 9 mg/m2 was given intravenously on days 4 and 18. Twelve of 48 patients (25%) achieved a major response (five, complete response and seven, complete response without platelet recovery). Ten of the 12 patients who achieved a major response survived >6 months compared with six of 36 non-responders. Serious adverse events for the oblimersen/GO combination were qualitatively similar to those reported for GO alone. Oblimersen can be safely combined with GO. Assessment of incremental benefit will require a randomized trial.

Acute Disease↗

PubMed2006

Survival benefit with imatinib mesylate versus interferon-alpha-based regimens in newly diagnosed chronic-phase chronic myelogenous leukemia.

A survival benefit for imatinib mesylate versus interferon-alpha therapy could not be demonstrated in the randomized study in newly diagnosed Philadelphia chromosome (Ph)-positive chronic-phase chronic myelogenous leukemia (CML) due to the high rate of crossover (90%) from interferon-alpha to imatinib mesylate within a year of study entry. We compared survival in 279 patients with newly diagnosed CML treated with imatinib mesylate at our institution (2000-2004) to 650 patients treated with interferon-alpha (1982-1997). The complete cytogenetic response rates were 87% with imatinib mesylate and 28% with interferon-alpha (P < .001). The estimated 3-year survival rates were 96% with imatinib mesylate and 81% with interferon-alpha (P < .01). Survival rates with imatinib mesylate were significantly better than with interferon-alpha within each of the CML prognostic risks groups. By multivariate analysis, imatinib mesylate therapy was identified as an independent favorable prognostic factor, after accounting for the impact of pretreatment factors (hazard ratio, 0.44; P < .01). By landmark analysis at 12 months, survival within each cytogenetic response category was similar with imatinib mesylate or interferon-alpha, suggesting that the survival benefit of imatinib mesylate (versus interferon-alpha in newly diagnosed CML) is through improving cytogenetic response.

Adolescent↗

PubMed2006

Circulating levels and clinical significance of soluble CD40 in patients with hematologic malignancies.

BACKGROUND: CD40 plays a critical role in immunoregulation, and CD40 ligation is being investigated as a therapy for hematologic malignancies. Although soluble CD40 (sCD40) is a potential modulator of both antitumor responses and CD40-based therapies, the levels and significance of sCD40 in patients with hematologic malignancies are unknown. METHODS: The authors evaluated serum/plasma sCD40 levels using an enzyme-linked immunoassay in patients with acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), chronic lymphocytic leukemia (CLL), mantle cell lymphoma (MCL), and multiple myeloma (MM). RESULTS: Levels of sCD40 were elevated in serum (>1.697 ng/mL) or plasma (>0.649 ng/mL) from 73% of patients with CLL, 80% of patients with MCL, 40% of patients with AML, 43% of patients with MDS, and 33% of patients with MM. Multivariate analysis of patients with MM demonstrated that elevated sCD40 was a significant, independent predictor of poor survival. In multivariate analysis of patients with AML, sCD40 was a significant prognostic factor when the interaction of age and sCD40 was included as a variable. Further analysis demonstrated that elevated sCD86 levels were associated with significantly shorter survival only in AML patients younger than age 64 years. Release of sCD40 by CLL cells was induced by cross-linking with CD40 monoclonal antibody. CONCLUSIONS: Many patients with hematologic malignancies have elevated circulating levels of sCD40, and these elevated levels are associated with a poor prognosis at least in patients with MM and AML, suggesting that sCD40 may have a role in modulating antitumor responses and also may be a useful prognostic marker. In addition, the findings suggested that further studies will be required to determine the effect of circulating sCD40 on the clinical effectiveness of CD40-ligating reagents used in the treatment of hematologic malignancies.

Biomarkers, Tumor↗

PubMed2006

Lenalidomide therapy in myelofibrosis with myeloid metaplasia.

We present results of 2 similarly designed but separate phase 2 studies involving single-agent lenalidomide (CC-5013, Revlimid) in a total of 68 patients with symptomatic myelofibrosis with myeloid metaplasia (MMM). Protocol treatment consisted of oral lenalidomide at 10 mg/d (5 mg/d if baseline platelet count < 100 x 10(9)/L) for 3 to 4 months with a plan to continue treatment for either 3 or 24 additional months, in case of response. Overall response rates were 22% for anemia, 33% for splenomegaly, and 50% for thrombocytopenia. Response in anemia was deemed impressive in 8 patients whose hemoglobin level normalized from a baseline of either transfusion dependency or hemoglobin level lower than 100 g/L. Additional treatment effects in these patients included resolution of leukoerythroblastosis (4 patients), a decrease in medullary fibrosis and angiogenesis (2 patients), and del(5)(q13q33) cytogenetic remission accompanied by a reduction in JAK2(V617F) mutation burden (1 patient). Grade 3 or 4 adverse events included neutropenia (31%) and thrombocytopenia (19%). We conclude that lenalidomide engenders an intriguing treatment activity in a subset of patients with MMM that includes an unprecedented effect on peripheral blood and bone marrow abnormalities.

Administration, Oral↗

PubMed2006

Allogeneic stem cell transplantation for patients with chronic myeloid leukemia and acute lymphocytic leukemia after Bcr-Abl kinase mutation-related imatinib failure.

Resistance to imatinib mesylate is an emerging problem in the treatment of chronic myeloid leukemia (CML), often associated with point mutations in the Bcr-Abl kinase domain. Outcome of patients with such mutations after allogeneic stem cell transplantation (Allo-SCT) is unknown. Ten imatinib-resistant patients with Bcr-Abl kinase mutations received a transplant: 9 had CML (3 in chronic phase, 4 in accelerated phase, and 2 in blast phase) and 1 had Philadelphia-positive acute lymphocytic leukemia (ALL). Patients harbored 9 different protein kinase mutations (T315I mutation, n = 2). Preparative regimens were ablative (n = 7) and nonablative (n = 3). All patients engrafted; there were no treatment-related deaths. Disease response was complete molecular (CMR; n = 7), major molecular (n = 2), and no response (n = 1). Three patients (mutations Q252H, E255K, and T315I) died of relapse after Allo-SCT. Seven patients are alive (6 in CMR) for a median of 19 months. Allo-SCT remains an important salvage option for patients who develop resistance to imatinib through Bcr-Abl mutations.

Adult↗

PubMed2006

Population pharmacokinetics of troxacitabine, a novel dioxolane nucleoside analogue.

PURPOSE: To develop and validate a population pharmacokinetic model for troxacitabine, a novel l-nucleoside analogue, administered by short infusion; to characterize clinical covariates that influence pharmacokinetic variability; and to design a dosage rate for continuous infusion administration to achieve low micromolar concentrations, which may be more efficacious than shorter infusions. EXPERIMENTAL DESIGN: Plasma samples from 111 cancer patients receiving troxacitabine (0.12-12.5 mg/m(2)) as a 30-minute infusion in phase I trials were used to develop the model with NONMEM. Clinical covariates evaluated included creatinine clearance, body surface area, age, and sex. From the model, a troxacitabine dosage rate of 2.0 to 3.0 mg/m(2)/d was expected to achieve a target concentration of 0.1 micromol/L; plasma samples were obtained during the infusion from eight patients receiving troxacitabine as a 3-day infusion. RESULTS: Troxacitabine pharmacokinetics were characterized by a three-compartment linear model. The mean value for systemic clearance [interindividual variability (CV%)] from the covariate-free model was 9.1 L/h (28%). Creatinine clearance and body surface area accounted for 36% of intersubject variation in clearance. Troxacitabine 2.0 mg/m(2)/d (n = 3) and 3.0 mg/m(2)/d (n = 5) for 3 days produced mean +/- SD end of infusion concentrations of 0.12 +/- 0.03 and 0.15 +/- 0.03 micromol/L, respectively. CONCLUSIONS: Renal function and body surface area were identified as sources of troxacitabine pharmacokinetic variability. The population pharmacokinetic model model-derived dosage rates for continuous infusion administration successfully achieved predetermined target plasma concentrations. The present model may be used to optimize treatment with troxacitabine by developing a dosing strategy based on both renal function and body size.

Antineoplastic Agents↗

PubMed2006

A phase II study of cloretazine (VNP40101M), a novel sulfonylhydrazine alkylating agent, in patients with very high risk relapsed acute myeloid leukemia.

Cloretazine (VNP40101M) is a sulfonylhydrazine alkylating agent with significant anti-leukemia activity. A multicenter phase II study of cloretazine was conducted in patients with first relapse of acute myeloid leukemia (AML) following an initial complete remission (CR) of less than 12 months. Cloretazine was given as a single intravenous infusion at a dose of 600 mg/m(2). Fifty-three patients (median age 62 years (18-84), 41 of 44 (93%) evaluable with intermediate or high risk cytogenetics, 32 (60%) with initial CR durations < or =6 months) were treated on study. Two patients (4%) achieved a second CR. Five (9%) patients died within 30 days of receiving cloretazine therapy. Median overall survival (2.3 months) in the study cohort was directly comparable to that of 233 matched patients treated with other single agents. The study cloretazine regimen had minimal activity in a very high risk subset of patients with relapsed AML.

Acute Disease↗

PubMed2006

Combined effects of novel tyrosine kinase inhibitor AMN107 and histone deacetylase inhibitor LBH589 against Bcr-Abl-expressing human leukemia cells.

AMN107 (Novartis Pharmaceuticals, Basel, Switzerland) has potent in vitro and in vivo activity against the unmutated and most common mutant forms of Bcr-Abl. Treatment with the histone deacetylase inhibitor LBH589 (Novartis) depletes Bcr-Abl levels. We determined the effects of AMN107 and/or LBH589 in Bcr-Abl-expressing human K562 and LAMA-84 cells, as well as in primary chronic myelogenous leukemia (CML) cells. AMN107 was more potent than imatinib mesylate (IM) in inhibiting Bcr-Abl tyrosine kinase (TK) activity and attenuating p-STAT5, p-AKT, Bcl-x(L), and c-Myc levels in K562 and LAMA-84 cells. Cotreatment with LBH589 and AMN107 exerted synergistic apoptotic effects with more attenuation of p-STAT5, p-ERK1/2, c-Myc, and Bcl-x(L) and increases in p27 and Bim levels. LBH589 attenuated Bcr-Abl levels and induced apoptosis of mouse pro-B BaF3 cells containing ectopic expression of Bcr-Abl or the IM-resistant, point-mutant Bcr-AblT315I and Bcr-AblE255K. Treatment with LBH589 also depleted Bcr-Abl levels and induced apoptosis of IM-resistant primary human CML cells, including those with expression of Bcr-AblT315I. As compared with either agent alone, cotreatment with AMN107 and LBH589 induced more loss of cell viability of primary IM-resistant CML cells. Thus, cotreatment with LBH589 and AMN107 is active against cultured or primary IM-resistant CML cells, including those with expression of Bcr-AblT315I.

Animals↗

PubMed2006

Long-term follow-up results of the combination of topotecan and cytarabine and other intensive chemotherapy regimens in myelodysplastic syndrome.

BACKGROUND: Progressive or higher-risk myelodysplastic syndrome (MDS) is often treated with intensive chemotherapy regimens used for acute myelogenous leukemia (AML). Patients with MDS are often older and may have contraindications to anthracycline-based regimens. Topotecan-cytarabine regimens have shown encouraging results in higher-risk MDS. The aim of this study was to analyze the long-term results with topotecan-cytarabine versus other intensive chemotherapy regimens in higher-risk MDS. METHODS: Five hundred ten patients with higher-risk MDS treated with intensive chemotherapy were reviewed. Their median age was 63 years; 82% had intermediate 2 or high-risk MDS; 32% had secondary MDS; 40% had chromosome 5 or 7 abnormalities. Therapy was: topotecan-cytarabine in 77; idarubicin-cytarabine regimens in 270; topotecan-cytarabine and cyclophosphamide in 67; fludarabine-cytarabine in 96. Univariate and multivariate analyses were conducted to evaluate the independent associations of different variables, and most important, the treatment regimen, with complete response, induction mortality, and survival. RESULTS: The overall complete response (CR) rate was 55%, induction mortality 17%, and 5-year survival rate 8%. The 5-year survival rate was 11% for patients younger than 65 years old and 17% for patients with a normal karyotype. Among 82 patients younger than 65 years with a normal karyotype, the CR rate was 67%, 5-year survival rate 27%, and 5-year CR duration rate 33%. Topotecan-cytarabine regimens were equivalent to idarubicin-cytarabine regimens in relation to CR rates and survival rates, but were associated with a lower induction mortality. Multivariate analysis confirmed that treatment regimens were not associated with independent significant differences in CR rates or survival. However, topotecan-cytarabine regimens were still selected to be associated with lower induction mortality rates. CONCLUSIONS: This analysis suggests that topotecan-cytarabine regimens are equally effective to other AML regimens in higher-risk MDS and may be less toxic. Topotecan-cytarabine may be considered a reasonable alternative to idarubicin-cytarabine in higher-risk MDS, particularly in older patients with contraindications to anthracyclines.

Age Factors↗