Nilotinib Exhibits an in Vitro Antiviral Activity Against Human Cytomegalovirus (HCMV): Potential Clinical Applications

Abstract Abstract 4666 Chronic myeloid leukemia (CML) is a clonal disorder associated with chromosomal translocation t (9; 22), which produces the Philadelphia chromosome. The fusion gene encodes for the chimeric oncoprotein BCR-ABL, associated with deregulated constitutive tyrosine kinase (TK) activity, leading to leukemogenesis. Imatinib mesylate, the first potent selective inhibitor of BCR-ABL TK, has revolutionized the current management of CML. The second generation TK inhibitor (TKI) Nilotinib (Novartis, East Hanover, NJ) is an aminopyrimidine derivative of imatinib with an increased binding affinity to the chimeric p210 BCR-ABL. Nilotinib is active in imatinib-resistant or -intolerant patients in chronic phase, accelerated phase (AP), and blast crisis (BC) CML. Allogeneic stem cell transplantation (SCT) is currently reserved for patients(pts) in CP after the failure of second line TKI or for patients in advanced phase disease.SCT remains the treatment of choice in patients with Ph+ALL. TKIs can be used successfully pre -SCT as a bridge to SCT in advanced disease and post-SCT in order to prevent disease recurrence. HCMV is one of the leading causes of morbidity and mortality post SCT in particular in pts transplanted for advance CML and pts with graft vs. host disease (GVHD) While preemptive antiviral therapy has reduced the occurrence of HCMV disease post SCT, the use of all currently available antiviral drugs is often limited by toxicity, low oral bioavailability, and drug resistance. The mechanisms facilitating HCMV entry into the host cells are not clearly understood. Blocking of the platelet – derived growth factor receptor-α (PDGFRα) has been shown to inhibit HCMV internalization and gene expression. Recently, Imatinib have been shown to inhibit PDGFRα phosphorylation. As Nilotinib is a more potent PDGFR inhibitor, we assessed the in vitro antiviral activity of Nilotinib against HCMV. Nilotinib exhibited a significant dose-dependent inhibition of the virus upon pre-incubation with the drug. Moreover, Nilotinib demonstrated a ∼4.5-fold higher antiviral activity against HCMV when compared to imatinib, with IC50 values of 0.39 μM and 1.75 μM, respectively. No viral inhibition was found upon addition of the drugs after viral adsorption – compatible with inhibition of an early step of infection, involving viral binding/entry into the cell. These findings identify a promising new target for antiviral therapy, representing an alternative paradigm for treatment with compounds combining anti-cancer and antiviral activity. It remains to be determined if the anti-HCMV activity demonstrated for Nilotinib is of clinical relevance in patients undergoing SCT Disclosures: No relevant conflicts of interest to declare.

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Hydroxychloroquine in Patients with Rheumatic Disease Complicated by COVID-19: Clarifying Target Exposures and the Need for Clinical Trials

The Journal of Rheumatology ◽

10.3899/jrheum.200493 ◽

2020 ◽

Vol 47 (9) ◽

pp. 1424-1430 ◽

Cited By ~ 5

Author(s):

Stephen J. Balevic ◽

Christoph P. Hornik ◽

Thomas P. Green ◽

Megan E.B. Clowse ◽

Daniel Gonzalez ◽

...

Keyword(s):

Clinical Trials ◽

Antiviral Activity ◽

Rheumatic Disease ◽

Rheumatic Diseases ◽

Pharmacokinetic Model ◽

Therapeutic Window ◽

Total Serum ◽

Viral Inhibition ◽

Target Exposure

Objective.To characterize hydroxychloroquine (HCQ) exposure in patients with rheumatic disease receiving longterm HCQ compared to target concentrations with reported antiviral activity against the coronavirus disease 2019 caused by SARS-CoV-2 (COVID-19).Method.We evaluated total HCQ concentrations in serum and plasma from published literature values, frozen serum samples from a pediatric systemic lupus erythematosus trial, and simulated concentrations using a published pharmacokinetic model during pregnancy. For each source, we compared observed or predicted HCQ concentrations to target concentrations with reported antiviral activity against SARS-CoV-2.Results.The average total serum/plasma HCQ concentrations were below the lowest SARS-CoV-2 target of 0.48 mg/l in all studies. Assuming the highest antiviral target exposure (total plasma concentration of 4.1 mg/l), all studies had about one-tenth the necessary concentration for in vitro viral inhibition. Pharmacokinetic model simulations confirmed that pregnant adults receiving common dosing for rheumatic diseases did not achieve target exposures; however, the models predict that a dosage of 600 mg once a day during pregnancy would obtain the lowest median target exposure for most patients after the first dose.Conclusion.We found that the average patient receiving treatment with HCQ for rheumatic diseases, including children and non-pregnant/pregnant adults, are unlikely to achieve total serum or plasma concentrations shown to inhibit SARS-CoV-2 in vitro. Nevertheless, patients receiving HCQ long term may have tissue concentrations far exceeding that of serum/plasma. Because the therapeutic window for HCQ in the setting of SARS-CoV-2 is unknown, well-designed clinical trials that include patients with rheumatic disease are urgently needed to characterize the efficacy, safety, and target exposures for HCQ.

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Autografting with cultured marrow in chronic myeloid leukemia: results of a pilot study [see comments]

Blood ◽

10.1182/blood.v84.3.724.724 ◽

1994 ◽

Vol 84 (3) ◽

pp. 724-732 ◽

Cited By ~ 108

Author(s):

MJ Barnett ◽

CJ Eaves ◽

GL Phillips ◽

RD Gascoyne ◽

DE Hogge ◽

...

Keyword(s):

Chronic Myeloid Leukemia ◽

Myeloid Leukemia ◽

Intensive Therapy ◽

Philadelphia Chromosome ◽

Chronic Phase ◽

Phase Group ◽

Cytogenetic Remission ◽

Group 2 ◽

Group 1

Abstract Incubation of chronic myeloid leukemia (CML) marrow for 10 days in vitro causes a marked and selective loss of very primitive Philadelphia chromosome (Ph)+ as compared with Ph- progenitors. We have autografted 22 patients with CML (16 in first chronic phase [group 1] and 6 with more advanced disease [group 2]) with marrow treated in this way to facilitate restoration of Ph- hematopoiesis after intensive therapy. Hematologic recovery to greater than 0.5 x 10(9)/L neutrophils occurred in 16 patients, and to greater than 20 x 10(9)/L platelets in 15 of 21 evaluable patients at a median of 29 and 48 days postautograft, respectively. Regenerating marrow cells were 100% Ph- in 13 patients and 75% to 94% Ph- in 3. Between 4 and 36 months (median 12) postautograft, Ph+ cells became detectable in all but 1 (who died in remission) of the 13 patients who achieved complete cytogenetic remission. Four of 7 evaluable patients treated with low-dose interferon alpha were returned to complete cytogenetic remission. Thirteen group 1 patients (81%) are alive 1.0 to 5.7 years (median 2.6) after autografting: 4 in complete cytogenetic remission, 2 in hematologic remission, 6 in chronic phase, and 1 in myeloid blast phase. Three group 2 patients (50%) are alive at 2.6, 3.8, and 4.3 years after autografting: 1 in partial cytogenetic remission, 1 in chronic phase, and 1 in accelerated phase. Thus, autografts of cultured marrow can result in prolonged restoration of Ph- hematopoiesis for some patients with CML.

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Phenotypic heterogeneity of primitive leukemic hematopoietic cells in patients with chronic myeloid leukemia

Blood ◽

10.1182/blood.v80.10.2522.2522 ◽

1992 ◽

Vol 80 (10) ◽

pp. 2522-2530 ◽

Cited By ~ 38

Author(s):

C Udomsakdi ◽

CJ Eaves ◽

PM Lansdorp ◽

AC Eaves

Keyword(s):

Chronic Myeloid Leukemia ◽

Myeloid Leukemia ◽

Philadelphia Chromosome ◽

Significant Proportion ◽

Hematopoietic Cells ◽

Chronic Phase ◽

Leukemic Cells ◽

Clonogenic Cell ◽

Clonogenic Cells

Abstract The peripheral blood of chronic myeloid leukemia (CML) patients with chronic-phase disease and elevated white blood cell (WBC) counts typically contains markedly increased numbers of a variety of neoplastic pluripotent and lineage-restricted hematopoietic progenitors. These include cells detected in standard colony assays as well as their more primitive precursors. The latter are referred to as long-term culture-initiating cells (LTC-IC) because of their ability to generate clonogenic cell progeny detectable after a minimum of 5 weeks incubation on competent fibroblast feeder layers. In this study, we have investigated a number of the properties of the LTC-IC and clonogenic cells present in the blood of such CML patients with high WBC counts. This included an analysis of the light scattering properties of these progenitors, as well as their expression of CD34 and HLA-DR, Rhodamine-123 staining, and in vitro sensitivity to 4- hydroperoxycyclophosphamide. In the case of LTC-IC, the production of different types of lineage-restricted and multipotent progeny was also analyzed. Most of the circulating LTC-IC and clonogenic cells in the CML patients studied (on average approximately 70% and approximately 90%, respectively) showed features of proliferating or activated cells. This is in marked contrast to the majority of progenitors in the blood of normal individuals and most of the LTC-IC in normal marrow, all of which exhibit a phenotype expected of quiescent cells. Interestingly, a significant proportion of the circulating clonogenic cells and LTC-IC in the CML samples studied (on average approximately 10% and approximately 30%, respectively) appeared to be phenotypically similar to normal circulating progenitors, although their absolute numbers were indicative of a neoplastic origin. Both phenotypes of circulating CML clonogenic cells and LTC-IC could be obtained at approximately 10% to 20% purity by differential multiparameter sorting. These findings suggest that expansion of the Philadelphia chromosome-positive clone at the level of the earliest types of hematopoietic cells results from the activation of mechanisms that enable some, but not all, signals that block the cycling of normal stem cells to be bypassed or overcome. In addition, they provide strategies for purifying these primitive leukemic cells that should facilitate further analysis of the mechanisms underlying their abnormal proliferative behavior.

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For CML Patients in Chronic Phase Who Achieve a Cytogenetic Response to Imatinib the Finding of a BCR-ABL Mutation Predicts for Progression to Advanced Phase but It Has No Such Significance in Primary Resistance.

Blood ◽

10.1182/blood.v110.11.323.323 ◽

2007 ◽

Vol 110 (11) ◽

pp. 323-323

Author(s):

Hugues de Lavallade ◽

Jamshid S. Khorashad ◽

Dragana Milojkovic ◽

Simon Wagner ◽

Jaspal Kaeda ◽

...

Keyword(s):

Adverse Effect ◽

Genomic Instability ◽

Direct Sequencing ◽

Chronic Phase ◽

Cytogenetic Response ◽

Molecular Response ◽

Primary Resistance ◽

Secondary Resistance ◽

Advanced Phase

Abstract We analysed outcome for 211 CML patients treated with imatinib in chronic phase (CP) (99 newly diagnosed and 112 late chronic phase) who were screened for BCR-ABL kinase domain (KD) mutations using direct sequencing regardless of the response status. When a mutation was found all available previous cDNA samples were analysed by pyrosequencing to establish the date of its first occurrence and subsequent kinetics. The median age of patients was 47.4 years. The Sokal risk score was ‘low’ in 57 patients, ‘intermediate’ in 82 and ‘high’ in 72. The median follow up from starting imatinib was 45 months (rage 6 to 89 months). A mutation was detected in 34 of the 211 patients (16%) at a median time of 27 months from starting imatinib. Twenty-two different mutations were identified, the most frequent being M244V (n=6) and F359V (n=3). When studied serially by pyrosequencing the size of the mutant subclone never exceeded 50% of total BCR-ABL transcripts in 8 patients, while in 17 patients it exceeded 90% on at least one occasion. 48 patients discontinued imatinib while still in CP and received either dasatinib, nilotinib or an allograft. The overall progression-free survival (absence of advanced phase) at 5 years was 73%. Major (MCyR) and complete (CCyR) cytogenetic responses were achieved by 153 and 123 patients respectively; 56 patients achieved major molecular response. 24% of the patient with up front cytogenetic resistance had a mutation while 40% of the patients with acquired cytogenetic resistance develop a mutation. In an-intention-to-treat analysis, patients harboring a mutant clone had a poorer PFS at 4 years (78% versus 57%, p=0.0014). The various mutations had no differential effects based on their known imatinib IC50. By multivariate analysis, factors associated with worse PFS were the presence of a KD mutation and failure to achieve CCyR (relative risks for PFS 2.6 and 8.7 respectively, p=0.002). Interestingly, the adverse effect of the presence of a KD mutation was restricted to the patients who achieved a MCyR (PFS 91% versus 62% at 5 years, p = 0.0006); it had no adverse impact on patients who failed to achieve a MCyR (PFS 42% and 49%, p=0.73). Similar results were found when the analysis was repeated according to the achievement of CCyR (data not shown). Surprisingly patients with a continuously low percentage (≤50%) of mutated vs wild type (>50%) clones fared worse than patients in whom the mutated clone became the predominant population (PFS 14% vs 69% respectively, p=0.0005). Comparable results were obtained when the patients were censored at the point of discontinuing imatinib, correcting for the effects of subsequent treatment, ie allografting (data not shown). The fact that the adverse effect of a mutation seems to be restricted to patients who had achieved cytogenetic response, the fact that mutations present at low level seemed to have a remarkable adverse effect and the fact that the in-vitro level of resistance to imatinib of the specific mutation did not affect the PFS could all be explained if the development of a mutation is only a reflection of the genomic instability of the disease that leads to secondary resistance to imatinib and eventually to transformation. Thus genomic instability may be less important in explaining primary resistance to imatinib and eventual transformation in patients with up-front resistance.

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Dasatinib in Children and Adolescents with Relapsed or Refractory Leukemia: Interim Results of the CA180-018 Phase I Study from the ITCC Consortium.

Blood ◽

10.1182/blood.v112.11.3241.3241 ◽

2008 ◽

Vol 112 (11) ◽

pp. 3241-3241 ◽

Cited By ~ 6

Author(s):

C. Michel Zwaan ◽

Carmelo Rizzari ◽

Vincent H.J. van der Velden ◽

Berna Beverloo ◽

M. L. den Boer ◽

...

Keyword(s):

Phase I ◽

Kinase Inhibitor ◽

Pediatric Population ◽

Philadelphia Chromosome ◽

Chronic Phase ◽

Dose Finding ◽

Cell Transplant ◽

Hematological Response ◽

Advanced Phase ◽

Grade 3

Abstract Relapsed/refractory leukemia in childhood carries a grave prognosis. Dasatinib (SPRYCEL®) is a potent oral kinase inhibitor of BCR-ABL, KIT, and SRC kinases. Dasatinib is approved for adults with Philadelphia chromosome-positive (Ph(+) CML and ALL, resistant or intolerant to prior imatinib therapy. An investigational phase I dose- finding study of dasatinib treatment of patients aged 1–21 years with various leukemia subtypes is currently being conducted in 12 European centers. The aim of the study is to establish a safe and effective dose for each of the leukemia sub-types. Patients were stratified into three treatment groups - Stratum 1: CML in chronic phase, resistant or intolerant to imatinib; Stratum 2/3: advanced-phase CML resistant or intolerant to imatinib, Ph(+) ALL, relapsed/ refractory after imatinib, or Ph(+) AML, ≥ 2nd relapse; Stratum 4: Ph(−) ALL, or Ph(−) AML in second/subsequent relapse. The starting dose was 60mg/m2 once daily for all strata. Intra-patient dose escalation was allowed for lack of initial response and dose reductions for toxicity. Current data reflect the first 41 patients (median age 11 years, range 1–21) treated from March 2006 through May 2008, including eight in Stratum 1, twelve in Stratum 2/3, and twenty-one in Stratum 4. The patients were heavily pretreated and prior therapy included chemotherapy (n=35), imatinib (n=20), and stem cell transplant (n=24). Dasatinib was well tolerated up to the current 120mg/m2 dose. Treatment-related toxicities were mostly mild to moderate in severity with nausea (34% grade 1/2; 2% grade 3/4) and diarrhea (15% grade 1/2; 0% grade 3/4) occurring most frequently. In Stratum 4, two dose-limiting toxicities were seen: anaphylaxis 5 hours after the first dose (60mg/m2) and upper-GI bleed on Day 6 of dasatinib dosing (120mg/ m2). Only one of the 41 patients experienced a malignant/hemorrhagic pleural effusion at 100mg/m2 dose. A maximum tolerated dose has not been established. PK studies were performed on samples from 32 patients after 60 mg/m2, 80 mg/m2 and 100 mg/m2 dosing. Absorption occurred rapidly (median Tmax 0.75 – 1.0 hour). The area under the curve (AUC) and maximum concentration (Cmax) proportionately increased with higher dose levels, but the difference was much greater between 60 and 80 mg/m2 than between 80 and 100 mg/m2. Complete Hematological Response (CHR) occurred in 75% of patients with CML-CP. Major Hematological Response (MaHR) was achieved in 25% of patients with advanced CML/Ph(+) and Ph(+) ALL/ AML. Major Cytogenetic Response occurred in 88% of CML-CP patients and 50% of patients with advanced Ph(+) CML and Ph(+) ALL/ AML. Stratum 4 observations included a temporary decrease in peripheral blood (PB) blast count in one Ph(−) ALL patient and in PB and bone marrow (BM) blast counts in two Ph(−) AML patients (one with AML7 and one with Down’s syndrome). Additionally, three Ph(+) ALL patients had a CSF response. These interim data demonstrate a favorable safety profile for dasatinib. Clear efficacy was seen in patients with CML-CP, and other Ph(+) leukemias. Further exploration is needed in the Ph(−) leukemias in the pediatric population. Updated data will be presented.

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Expression of Biomarkers That Predict Progression in Chronic Myeloid Leukemia

Blood ◽

10.1182/blood.v112.11.4241.4241 ◽

2008 ◽

Vol 112 (11) ◽

pp. 4241-4241

Author(s):

Mariana Selena Gonzalez ◽

Patricia Martha Gargallo ◽

Beatriz Moiraghi ◽

Irene Larripa

Keyword(s):

Myeloid Leukemia ◽

Philadelphia Chromosome ◽

Chronic Phase ◽

Apoptotic Index ◽

Myelogenous Leukemia ◽

Control Group ◽

Qrt Pcr ◽

Advanced Phase ◽

Bmi1 Expression ◽

Healthy Donors

Abstract Chronic Myelogenous Leukemia (CML) is associated with a chromosomal translocation, t(9;22)(q34;q11.2), that produces the Philadelphia chromosome (Ph). The molecular consequence of this translocation is the generation of the BCR/ABL oncogene, which encodes a chimeric protein of 210 kDa (p210Bcr/Abl) with elevated tyrosine kinase activity. BCR/ABL exerts its oncogenic effect in CML cells essentially by stimulating cell proliferation, inhibiting apoptosis and altering cell adhesion to bone marrow stroma. Despite of this consistent molecular abnormality, a marked heterogeneity in prognosis and response to treatment has been reported. Different molecular markers have been studied, such as: BMI1, ELA2, PR3, E2F1 and apoptotic genes (BCL-2, BCL-XL, BAX, BAD, BAK) in order to predict progression and overall survival in myeloid leukemia. The polycomb group gene BMI1 plays an essential role in regulating the proliferative activity in leukemic stem cell. The expression of this gene is related to a higher degree of malignancy. On the other hand, BCL-2 family genes involved in the mitochondrial-apoptotic pathway are related with clinical response and treatment failure. Enhanced expression of the apoptotic inhibitor BCL-2 or its homolog BCL-XL lead to tumor cells having a decreased susceptibility to cell death. Other BCL-2 family members such as BAX are able to induced apoptosis, so that the ratio of expression of proapoptotic and anti-apoptotic members might determine the apoptotic potencial of cancer cells. In this study we evaluated the expression of BMI1 and BAX/BCL-XL ratio (apoptotic index) to determine whether these genes could behave as biomarkers to predict disease aggressiveness and progression from chronic phase to more advanced phases. Total RNA was extracted from leucocytes of peripheral blood. using Trizol method. cDNA was synthesized with random hexamer primers and reverse transcriptase. The expression was assessed by quantitative real time (QRT-PCR) using the LightCycler 2.0 instrument (Roche), based on the Syber-Green method. All QRT-PCR reactions were performed in 20ul volume. The β-actin expression was used as the endogenous cDNA quality control. Groups of patients were compared using the Mann-Whitney test. The study was performed in 31 patients: 16 in chronic phase (CP), 15 in advanced phases (accelerated and blast crisis) and 10 healthy donors (control group). BMI1 expression levels were significantly lower in CP (mean ± SEM: 0.54±0.15) than in more advanced stages of CML (mean ± SEM: 4.54±1.4) (P<0.0005). In peripherical blood of healthy donors, the expression of this gene was similar to CML-CP patients (0.4±0.13). The relationship of BAX/BCL-XL values were higher in CP (mean ± SEM: 13.81± 1.85) and lower in advanced phase (mean ± SEM: 0.88±0.17) than in the control group (mean ± SEM: 4.82 ± 0.49) (P<0.0044 and P< 0.0002, respectively). The CP patients showed a low BMI1 expression level and a high apoptotic index, this inverse correlation is associated with a benign stage of the disease and good treatment response. On the contrary, cases in more advance stage displayed overexpression of BMI1 gene and low BAX/BCL-XL ratio suggesting an aggressive stage and poor response. The identification of a genetic hostile profile in CP phase could predict an impending disease progression. Our results show that the simultaneous use of two biomarkers: BMI1 and the ratio BAX/BCL-XL represent sensitive indicators of clinical outcome in CML-CP. Therefore, the prospective screening of these biomarkers would help to refine CML disease staging and would be useful prognostic indicators for optimizing therapeutic strategies.

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Response and Outcomes to Nilotinib at 24 Months in Imatinib-Resistant Chronic Myeloid Leukemia Patients in Chronic Phase (CML-CP) and Accelerated Phase (CML-AP) with and without BCR-ABL Mutations.

Blood ◽

10.1182/blood.v114.22.1130.1130 ◽

2009 ◽

Vol 114 (22) ◽

pp. 1130-1130 ◽

Cited By ~ 1

Author(s):

Jerald P. Radich ◽

Giovanni Martinelli ◽

Andreas Hochhaus ◽

Enrico Gottardi ◽

Simona Soverini ◽

...

Keyword(s):

Board Of Directors ◽

Median Time ◽

Research Funding ◽

Philadelphia Chromosome ◽

Chronic Phase ◽

Cytogenetic Response ◽

Molecular Response ◽

Advisory Committees ◽

Imatinib Resistant

Abstract Abstract 1130 Poster Board I-152 Background Nilotinib is a selective and potent BCR-ABL inhibitor, with in vitro activity against most BCR-ABL mutants (excluding T315I) indicated for the treatment of patients with Philadelphia chromosome positive (Ph+) CML in CPor AP resistant or -intolerant to prior therapy, including imatinib. In a previous analysis of nilotinib in patients with BCR-ABL mutations, mutations occurring at three specific amino acid residues (E255K/V, Y253H, and F359C/V) were shown to be associated with less favorable response to nilotinib. The current analysis is based on mature data with a minimum follow-up of 24-months for all patients. Outcomes of patients at 24 months were analyzed by mutation type. Methods Imatinib-resistant CML-CP (n = 200) and CML-AP (n = 93) patients were subdivided into the following mutational subsets: no mutation, sensitive mutations (including mutations with unknown in vitro IC50). or E255K/V, Y253H, or F359C/V mutations at baseline. Patients with mutations of unknown in vitro sensitivity were classified as sensitive in this analysis based on a previous finding that patients with these mutations responded similarly to nilotinib as patients with sensitive mutation. Patients with baseline T315I mutations were excluded from this analysis. Patient groups were analyzed for kinetics and durability of cytogenetic and molecular response to nilotinib, as well as event-free survival (EFS), defined as loss of hematologic or cytogenetic response, progression to AP/BC, discontinuation due to disease progression, or death, and overall survival (OS). Results In CML-CP and -AP patients with no mutation, sensitive mutations, or E255K/V, Y253H, or F359C/V mutations, hematologic, cytogenetic and molecular responses are provided in the Table. Overall, patients with no mutations responded similarly to patients with sensitive mutations, whereas patients with E255K/V, Y253H, or F359C/V mutations had less favorable responses. This correlation was observed in both CML-CP and CML-AP patients, respectively. Median time to CCyR was 3.3 months (range, 1.0–26.7) for CML-CP patients with no mutations, and 5.6 months (range, 0.9–22.1) for patients with sensitive mutations. At 24 months, CCyR was maintained in 74% of CML-CP patients with no mutation and in 84% of patients with sensitive mutations. One patient with CML-CP and an E255K mutation achieved CCyR at 25 months and maintained until last assessment at 30 months. Median time to MMR was similar at 5.6 months (range, 0.9–25.8) for CML-CP patients with no mutations and 5.6 months (range, 2.7–22.1) for patients with sensitive mutations. No patient with a less sensitive mutation achieved MMR. Median EFS and 24-month estimated OS rate are provided in the Table. Conclusions Imatinib-resistant CML-CP and CML-AP patients treated with nilotinib therapy with BCR-ABL mutations (excluding E255K/V, Y253H, or F359C/V) achieved rapid and durable cytogenetic responses, and estimated EFS and OS at 24 months similar to that of patients with no mutations, respectively. Patients with E255K/V, Y253H, or F359C/V mutations had lower and less-durable responses and shorter EFS than patients with sensitive mutations. Alternative therapies may be considered for patients with these uncommon mutations (E255K/V, Y253H, and F359C/V). Disclosures Radich: Novartis: Consultancy, Honoraria, Research Funding. Hochhaus:Novartis: Research Funding. Branford:Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding. Shou:Novartis: Employment. Haque:Novartis: Employment. Woodman:Novartis: Employment. Kantarjian:Novartis: Research Funding. Hughes:Bristol-Myers Squibb: Advisor, Honoraria, Research Funding; Novartis: Advisor, Honoraria, Research Funding. Kim:Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Wyeth: Research Funding. Saglio:Novartis: Consultancy, Speakers Bureau; BMS: Consultancy, Speakers Bureau.

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Dasatinib Cerebrospinal Fluid Concentration and Plasma Pharmacokinetics: Potential for Central Nervous System Prophylaxis In Philadelphia Chromosome-Positive Leukemia

Blood ◽

10.1182/blood.v116.21.1807.1807 ◽

2010 ◽

Vol 116 (21) ◽

pp. 1807-1807

Author(s):

Naoto Takahashi ◽

Masatomo Miura ◽

Stuart Scott ◽

Hirobumi Saitoh ◽

Mutsuhito Motegi ◽

...

Keyword(s):

Central Nervous System ◽

Cerebrospinal Fluid ◽

Nervous System ◽

Conflicts Of Interest ◽

Philadelphia Chromosome ◽

T Test ◽

Lymphoid Leukemia ◽

Csf Levels ◽

Philadelphia Chromosome Positive

Abstract Abstract 1807 Dasatinib (DA) is approved for use in imatinib-resistant or intolerant chronic myeloid leukemia (CML)/Philadelphia-positive acute lymphoid leukemia (Ph+ALL) and may also be useful for central nervous system (CNS) leukemia accompanied with CML/Ph+ALL; however, little is known about the relationship between DA pharmacokinetics and its ability to penetrate the blood-brain barrier. Consequently, we measured DA plasma and cerebrospinal fluid (CSF) levels by high-performance liquid chromatography in 20 samples obtained from 11 DA-treated patients (seven Ph+ALL and four lymphoid crisis CML). DA was detected in 10 CSF samples from five patients who were treated with 100 mg QD of DA (CSF C4h of detectable group; 3.526±2.604 ng/mL, 1.11–7.95 ng/mL), which was above the IC50 level for wild type BCR-ABL positive leukemia cells in vitro (0.8 nM = 0.39 ng/mL). However, DA was not detected in 10 CSF samples from 7 patients (CSF C4h of non-detectable group; <1.0 ng/mL). The concentration ratio of CSF to plasma was 3.90% (0.42-12.23%), which approached previously reported ratios for imatinib. There were significant differences in the AUC0-4 and the plasma C4h between the CSF detectable (D) and non-detectable (ND) patients (AUC0-4: 268.29±92.452 vs. 90.83±76.45, P=0.00019 by Student t-test, Figure 1; plasma C4h: 126.15±62.58 vs. 47.41±50.935, P=0.00637 by Student t-test). Moreover, there were significant correlations between CSF C4h and AUC0-4 (P<0.01, Figure 2) and between CSF C4h and plasma C2h (P<0.001), together suggesting that penetration of DA into the CSF may depend on DA plasma concentration. To investigate any influence of pharmacogenetic variation on CSF penetration, single nucleotide polymorphisms in genes involved in DA pharmacokinetics and transport (ABCB1, ABCG2, SLC22A1, SLC22A3, and CYP3A4/5) were interrogated; however, no significant correlation between CSF levels and genotype were observed. DA has a 325 fold greater potency than imatinib for inhibiting BCR-ABL tyrosine kinase, which undoubtedly influences the efficacy of DA for Philadelphia-chromosome positive CNS leukemia; however, our data suggest that clinical DA blood level monitoring may help estimate the penetration of DA to the CSF. Disclosures: No relevant conflicts of interest to declare.

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CBL, CBLB, TET2, ASXL1, and IDH1/2 Mutations as Well as Additional Chromosomal Aberrations Constitute Molecular Events Contributing to Malignant Progression In Advanced Philadelphia Chromosome-Positive Disorders.

Blood ◽

10.1182/blood.v116.21.3396.3396 ◽

2010 ◽

Vol 116 (21) ◽

pp. 3396-3396

Author(s):

Hideki Makishima ◽

Anna Jankowska ◽

Michael A McDevitt ◽

Simon Dujardin ◽

Heather Cazzolli ◽

...

Keyword(s):

Clinical Features ◽

Copy Number ◽

Chromosomal Abnormalities ◽

Philadelphia Chromosome ◽

Chronic Phase ◽

Kinase Domain ◽

Chromosome 8 ◽

Molecular Events ◽

Advanced Phase ◽

Imatinib Resistant

Abstract Abstract 3396 Chronic myeloid leukemia (CML) is characterized by the BCR/ABL fusion gene. However, secondary molecular events leading to accelerated (AP) or blast phase (BP) have not been sufficiently clarified. We hypothesized that, in analogy to other MDS/MPN or MPN, TET2, ASXL1, CBL and IDH family mutations may also occur in CML and contribute as secondary events leading to progression to AP or BP. Similarly, higher resolution of cytogenetic testing by single nucleotide polymorphism array (SNP-A)-based karyotyping may reveal additional chromosomal abnormalities associated with stepwise progression. This study is focused on the combined analysis of chromosomal lesions and mutations associated with AP, BP and Philadelphia chromosome (Ph) positive acute lymphoblastic leukemia (ALL) and the association of these defects with clinical features. We screened TET2, ASXL1, CBL and IDH for mutations in AP (N=14) and BP (N=26) and Ph+ ALL (N=9). Chronic phase (CP) (N=14) and Ph negative ALL (N=9) served as controls. We identified 3 CBL family (9%), 7 TET2 (21%), 2 ASXL1 (6%) and 2 IDH family (6%) mutations in patients with AP and myeloid BP. Subsequently, we also detected a TET2 mutation in a case of Ph+ ALL. None of these mutations were found in patients with CP or Ph negative ALL. We also performed SNP-A-based karyotyping and only included lesions which did not overlap with copy number variations (CNVs) or germ line regions of homozygosity present in any of the controls. 23 gains, 21 losses and 4 regions of somatic UPD lesions were identified. By SNP-A, additional copy number abnormalities, including microdeletions were found in 67% and 50% of patients with AP and BP, respectively. Recurrent lesions were detected on chromosome 1, 8, 9, 17 and 22. Microdeletions on chromosome 17 and 21 involved tumor associated genes NF1 and RUNX1. Deletions flanking the ABL1 and BCR genes were observed in 3 cases with der(22)t(9;22) or der(9)t(9;22) by metaphase cytogenetics. Gains including 1q25.3q41, chromosome 8 and 17q24.3 were found in 3 cases. Regions of UPD included UPD5q, 8q, 11p and 17q but no UPD involving 11q (CBL) and 4q (TET2) regions were found confirming heterozygous nature of the corresponding mutations. Newly detected molecular lesions associated with AP and BP may change the biology and thereby clinical features of affected cases. Overall survival of patients with mutations did not differ from those without mutations. Of note is that BCR/ABL1 kinase domain mutations were detected in 9/10 patients with imatinib resistance. In these 9 cases, 3 TET2 and 2 CBLB mutations were detected (but no mutations in the other genes). In an imatinib-resistant patient without BCR/ABL1 kinase domain mutation, CBL mutation was present. In the patients with TET2 mutations, additional chromosomal lesions were found by SNP-A, significantly more frequently when compared with WT cases (P=0.017). Of the 9 TET2 variants in 8 cases, 7 (78%) were missense substitutions, 1 (11%) was frame shift and 1 (11%) produced a stop codon and were located within the N-terminus as well as in a conserved DSBH 2OG-Fe(II)-dependent dioxygenase domain. The presence of nonsense and frameshift mutations suggests that mutated lesions result in inactivation, consistent with putative tumor suppressor functions, while heterozygous mutations indicate that the wild type allele is not completely protective. Since no TET2 mutations were identified in chronic phase CML, these mutations might represent an additional pathogenic event and contribute to progression. In 3 cases we observed a combination of 2 mutations. Coincidence of CBLB and TET2 mutations in 2 cases suggests that these might cooperate in the evolution of advanced phase of CML. We also found a combination of IDH1 and ASXL1 mutations in a patient with BP, suggesting that both mutations contribute to clonal advantage. In conclusion, while CBL family, ASXL1 and IDH family mutations as well a additional unbalanced chromosomal abnormalities not seen by metaphase cytogenetics can occur in myeloid type advanced phase CML, TET2 mutations were identified in Ph+ ALL, as well as myeloid BP and AP. These mutations likely represent secondary lesions which contribute to either disease progression or more aggressive features and commonly occur in association with imatinib-resistant BCR/ABL mutations. Disclosures: No relevant conflicts of interest to declare.

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ABL Mutations In Early Chronic Phase Chronic Myeloid Leukemia (CP-CML) Are Associated with a Greater Likelihood of Progression and Shorter Survival

Blood ◽

10.1182/blood.v116.21.4458.4458 ◽

2010 ◽

Vol 116 (21) ◽

pp. 4458-4458

Author(s):

A. M. Carella ◽

A. Garuti ◽

G. Cirmena ◽

G. Catania ◽

G. Pica ◽

...

Keyword(s):

Conflicts Of Interest ◽

Acquired Resistance ◽

Chronic Phase ◽

Kinase Domain ◽

Imatinib Treatment ◽

Cycle Sequencing ◽

Advanced Phase ◽

Blastic Phase ◽

The Status ◽

Risk Patients

Abstract Abstract 4458 Acquired resistance to Imatinib in advanced phase of CML has been associated with mutations in the kinase domain (KD) of BCR-ABL. We have recently reviewed the status of the mutations in 52 patients with early CP-CML on the samples collected at diagnosis. Mutations were identified by direct sequency (DS) with BidDye Terminator V1.1. cycle sequencing kit and analyzed with a 3130 AB capillary electrophoresis system. Twenty-eight patients had low risk, 10 intermediate risk and 14 high risk, according to Sokal/Euro. Ten out of 14 high Sokal risk patients showed the following mutations: Y253C, S265R, E255K, F359Y, N374S, E255V, E255V, E255V, R332L, E334G. Three of these patients progressed during Imatinib and second-line TKIs and died of blastic phase CML at 23, 33 and 69 months. Curiously, S265R and N374S mutations disappeared during Imatinib treatment but were substituted during follow-up by other two mutations: E255L and H396R. The patient carrying E255L mutation died in blastic phase at 33 months and the one with mutation H396R was well controlled by Nilotinib and he is now alive in CMR 26 months after. Only one out of the 10 intermediate Sokal risk carried KD mutations at diagnosis (D363G). This patient is alive in MMR at 26 months after diagnosis under Imatinib. None of the 28 low Sokal risk patients carried KD mutations at diagnosis and no patients developed cytogenetic evolution while on treatment. In conclusion, the fact that KD mutations were more present in patients with high Sokal risk supports the hypothesis that the probability developing a mutation is related to the basic biology of the disease rather than being merely a random event. Disclosures: No relevant conflicts of interest to declare.

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