Generation Tyrosine Kinase Inhibitors Nilotinib Research Articles

The new generation tyrosine kinase inhibitor improves the survival of chronic myeloid leukemia patients after allogeneic stem cell transplantation.

The introduction of tyrosine kinase inhibitors (TKIs) in chronic myeloid leukemia (CML) treatment has dramatically improved the prognosis of CML patients and reduced the number of patients receiving allogeneic stem cell transplantation (allo-SCT). However, the impact of the newest-generation TKIs on the overall survival (OS) after allo-SCT has not been well described. To investigate the beneficial effects of TKIs on the prognosis after allo-SCT, we conducted a retrospective observational study using the Transplant Registry Unified Management Program database in Japan. We analyzed 1188 patients (male/female: 738/450; median age: 44years; range: 16-75) who underwent their first allo-SCT between January 2001 and December 2018. We divided the patients into two groups according to the TKI treatment used before allo-SCT: group 1 was treated with the first generation TKI imatinib; group 2 was treated with the second generation TKIs nilotinib, dasatinib, or bosutinib and/or the third generation TKI ponatinib. We compared the post allo-SCT OS between the two groups. The 3-year OS rates (95%CI) of groups 1 and 2 were 59.3% (54.8%-63.5%) and 65.8% (61.6%-69.6%), respectively (p=0.017). Multivariate analysis confirmed that group 2 had superior OS after allo-SCT compared to group 1 (p=0.002). Other factors associated with superior prognosis were age ≤65, performance status (PS) 0/1, a 6/6 HLA-matched donor and chronic-phase (CP) disease status at allo-SCT. A subgroup analysis showed poor prognoses for patients who could not obtain a molecular response before allo-SCT and patients with positive T315I mutation in the BCR/ABL gene. In group 2, early allo-SCT was correlated with superior OS in patients with a blast-crisis disease status at allo-SCT (p=0.001). The cumulative incidence of non-relapse mortality rate significantly decreased in group 2 (p=0.0005). The post allo-SCT OS was improved both by pre- and post-management of allo-SCT and by the introduction of newer TKIs.

Genetic risk of prediabetes and diabetes development in chronic myeloid leukemia patients treated with nilotinib

Impaired fasting glucose and type 2 diabetes represent adverse events in patients with chronic myeloid leukemia (CML) treated with the second generation tyrosine kinase inhibitor nilotinib. An unweighted genetic risk score (uGRS) for the prediction of insulin resistance, consisting of 10 multiple single-nucleotide polymorphisms, has been proposed. We evaluated uGRS predictivity in 61 CML patients treated with nilotinib. Patients were genotyped for IRS1, GRB14, ARL15, PPARG, PEPD, ANKRD55/MAP3K1, PDGFC, LYPLAL1, RSPO3, and FAM13A1 genes. The uGRS was based on the sum of the risk alleles within the set of selected single-nucleotide polymorphisms. Molecular response (MR)3.0 and MR4.0 were achieved in 90% and 79% of patients, respectively. Before treatment, none of the patients had abnormal blood glucose. During treatment and subsequent follow-up at 80.2 months (range: 1-298), seven patients (11.5%) had developed diabetes that required oral treatment, a median of 14 months (range: 3-98) after starting nilotinib treatment. Twelve patients (19.7%) had developed prediabetes. Prediabetes/diabetes-free survival was significantly higher in patients with a uGRS <10 than in those with higher scores (100% vs. 22.8 ± 12.4%, p <0.001). Each increment of one unit in the uGRS caused a 42% increase in the prediabetes/diabetes risk (hazard ratio = 1.42, confidence interval: 1.04-1.94, p = 0.026). The presence of more than 10 allelic variants associated with insulin secretion, processing, sensitivity, and clearance is predictive of prediabetes/diabetes development in CML patients treated with nilotinib. In clinical practice, uGRS could help tailor the best tyrosine kinase inhibitor therapy.

Treatment Outcomes in Patients Treated with Tyrosine Kinase Inhibitors in "Slovak Registry of Chronic Myeloid Leukemia" (CAMELIA SK)

Introduction: With the onset of tyrosine kinase inhibitors (TKI) to treat patients with CML, the number of patients and overall survival increased and quality of life significantly improved. The basic principle of therapy was also changed, according to the clinical practice now it is aimed at early induction of deep molecular response.Objective: To characterize the CML patient population and TKI treatment results in clinical practice in CML patients in Slovak republic (SR).Methods: The observational study "Slovak registry of chronic myeloid leukemia" (CAMELIA SK) was launched in 2005 by Novartis. Patients with Ph+ CML were enrolled into study after signing the informed consent. Thus the study has a retrospective part (131 patients) and prospective group of 586 CML patients. By June 2016, the Registry contained information about 717 patients from 7 centers of SR. The annual increase of newly diagnosed CML cases ranged from 2 to 56 people per year (median 35.5). Characteristics of patients in the Registry: in June 2016, 489 (68.2%) were alive, 181 (25.2%) dead and 47 (6.6%) lost to follow-up. Median follow-up in alive patients was 79 months (1 to 324 months). Median age at CML diagnosis was 50 years (range 15 - 86 years); male 52.7%. Chronic phase (CP) was in 664 (92.6%), accelerated phase in 37 (5.2%) and blast crisis in 16 (2.2%) patients. Sokal risk group's ratio was 35.8%/34.3%/25.7%/4.2% for low, intermediate, high risk and unknown, respectively. Hasford risk group's ratio was 41.6%/40.6%/13.4%/4.5% for low, intermediate, high risk and unknown, respectively, and EUTOS risk group's ratio was 83.8%/11.7%/4.5% for low, high risk and unknown, respectively.Results: The data for this analysis were available for 594 patients (82.8% of patients in the Registry) treated by tyrosinkinase inhibitors (TKI). First line TKI treatment was initiated in 467 patients: 363 (77.7%) started imatinib (IM), 101 (21.6%) nilotinib (NIL) and 3 (0.7%) dasatinib (DAS). Higher line TKI treatment was initiated in 127 patients, mostly after interferon-alpha or allogeneic stem cell transplantation (SCT), 125 (98.4%) of them started IM and 2 (1.6%) NIL. Time from diagnosis until first line TKI treatment was 0-112.7 months (median 1.1). One TKI drug was used in 388 (65.3%) patients, 2 drugs in 146 (24.6%), 3 drugs in 57 (9.6%) and 4 drugs in 3 (0.5%) patients.From these 594 patients, 448 (75.4%) are alive, 28 (4.7%) are lost to follow-up and 118 (19.9%) died, mostly because of other diseases - 50%; 30.5% died because of CML, 17.8% because of disease progression and 1.7% by SCT.From 363 patients who started first line IM (93.7% in CP), optimal treatment response from evaluable patients according to ELN2013 achieved 57.8%, 49.2%, 17.3%, 27.9% and 36.5% after 3, 6, 12, 24 and 48 months, respectively. Median length of treatment was 39.6 months (0.2-149.1). Change of treatment to 2ndline was performed in 155 (42.7%) patients. In total, 264 (72.7%) patients are still on TKI treatment, 3 (0.8%) progressed to advanced phase, 5 (1.4%) underwent SCT and 42 (11.6%) patients are lost to follow up, had adverse events (AE) or discontinued treatment from other reasons. The death occurred in 49 (13.5%) patients.From 101 patients who started first line NIL (98% in CP), optimal treatment response from evaluable patients according to ELN2013 achieved 82.4%, 82.6%, 59.3%, 66.6% and 83.3% after 3, 6, 12, 24 and 48 months, respectively. Median length of treatment was 18.4 months (0.2-97). Change of treatment to 2ndline was performed in 11 (10.9%) patients. In total, 87 (86.4%) patients are still on TKI treatment, nobody progressed to advanced phase and 10 (9.7%) patients are lost to follow up, had AE or discontinued treatment from other reasons. The death occurred in 4 (3.9%) patients.53 patients in accelerated or blastic phase started mostly IM treatment (18, 34%), combined chemotherapy (12, 22.6%) or interferon-alpha (9, 17%). 4 patients underwent SCT, 2 started NIL, 2 DAS and 6 another treatment. In total, 35.8% patients are alive, 52.8% died and 11.3% are lost to follow up.Conclusions: The observational study "CAMELIA SK" is the largest registry of hematological diseases in Slovakia, providing information about CML patients receiving TKI therapy more than 10 years. We approved the efficacy and safety of second generation TKI nilotinib in newly diagnosed CML patients as first line therapy. More patients achieved optimal response in short period than on imatinib. DisclosuresNo relevant conflicts of interest to declare.

Prevalence and Dynamics of BCR-ABL Independent Gene Mutations in Patients with Chronic Myeloid Leukemia

Living without treatment has become a realistic target for patients with chronic myeloid leukemia (CML) who achieved durable deep molecular remission under treatment with tyrosine kinase inhibitors (TKI). Recently, we have identified novel BCR-ABL-independent gene mutations in newly diagnosed CML patients that may function as important cofactors in the evolution of CML and persistence of the disease (Schmidt M, Rinke J, et al. Leukemia 2014; 28(12): 2292-9). Here, we sought to investigate the dynamics of such mutations during a 2-year treatment with the second generation TKI nilotinib. To check if BCR-ABL independent mutations are an age associated phenomenon we also screened a cohort of children and adolescents with CML. A total of 51 chronic phase CML patients were analyzed including 31 adults (male, n=23; median age 57 years, range 42 to 73 years) and 20 children/adolescents (male, n= 14; median age 14 years, range 10 months to 27 years). For each adult patient, samples were analyzed at diagnosis, in subsequent complete cytogenetic remission (CCyR) after 3 months and in deep molecular remission (≤ MMR) after 24 months of nilotinib therapy. Children/adolescents samples were investigated at diagnosis only. Targeted deep next-generation sequencing (NGS) was used to analyze a panel of 30 commonly mutated genes in myeloid disorders. Constitutional DNA obtained from buccal swabs at diagnosis was investigated to check whether mutations are of somatic origin. BCR-ABL independent gene mutations were found in 8/31 (26%) adult CML patients at diagnosis affecting the genes ASXL1 (n=3), DNMT3A (n=3), RUNX1 (n=1) and RUNX1 plus TET2 (n=1). No mutation was recognized in corresponding constitutional DNA specimens indicating that all mutations were somatically acquired. Analysis of individual hematopoietic colonies from three adult patients revealed that most mutations were part of the BCR-ABL-positive clone. NGS of subsequent samples obtained after three months of TKI therapy identified two DNMT3A mutations in BCR-ABL-negative cells that were also present in BCR-ABL-positive cells at diagnosis, implying that this mutation preceded the BCR-ABL rearrangement. After 24 months of TKI treatment, NGS revealed these two DNMT3A mutations again as well as a novel low-level EZH2 mutation in a patient with deep molecular remission (MR4.5) that was neither detectable at diagnosis nor after 3 months of treatment indicating the emergence of a BCR-ABL-independent subclone in BCR-ABL-negative cells during long-term nilotinib treatment. Within the children/adolescents cohort BCR-ABL independent gene mutations were identified in 5/20 (25%) subjects all affecting the ASXL1 gene. All mutations were stop codon or frameshift mutations implying loss of ASXL1 gene function. We conclude that BCR-ABL independent gene mutations can be found frequently in CML patients and affect predominately epigenetic modifier genes. The finding of frequent mutations also in children/adolescents implicates that BCR-ABL independent gene mutations are not just age-related events. Such molecular aberrations may play an important role in the evolution and persistence of the disease and may affect therapy in both children and adults with CML. These findings may provide important novel genetic information regarding CML biology and for the design and performance of discontinuation trials. DisclosuresHochhaus:Novartis: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; BMS: Honoraria, Research Funding; ARIAD: Honoraria, Research Funding.

Cardiovascular side effects of small molecule therapies for cancer.

Targeted therapies such as monoclonal antibodies and small molecule inhibitors of protein kinases, have improved the prognosis for patients with a wide range of cancers. Several of these classes of therapies are associated with cardiovascular and metabolic sequelae. These include heart failure or an asymptomatic decline in ejection fraction, peripheral and cardiac ischemic events, pulmonary hypertension, arrhythmias and QT-prolongation. This review will focus on the following targeted therapies: BCR-Abl tyrosine kinase inhibitors (TKI), vascular endothelial growth factor (VEGF) signaling pathway (VSP) inhibitors as well as mitogen activated protein kinase (MEK) inhibitors and mammalian target of rapamycin complex (mTOR) inhibitors. The HER2/ErbB2 inhibitors trastuzumab and pertuzumab are important targeted therapies used in the treatment of breast cancer that have been reviewed in detail elsewhere and will not be discussed in this review.1 Table 1 summarizes the cardiovascular side effects of small molecule therapies for cancer.2 View this table: Table 1 Cardiovascular Side effects of Small Molecule Therapies for Cancer BCR-Abl tyrosine kinase inhibitors are an important advance in the treatment of chronic myelogenous leukemia (CML) and the cardiovascular side effects have been extensively reviewed by Moslehi et al.3 Imatinib, a first generation TKI was followed by the second generation TKIs nilotinib, dasatinib and bosutinib and the third-generation agent ponatinib. Imatinib has a low incidence of cardiomyopathy and heart failure, with sequential imaging studies demonstrating rates of left ventricular dysfunction comparable to expected population incidence.4 The heart failure and cardiomyopathy rates for dasatinib were similar …

LONG-TERM RESULTS OF TARGET THERAPY WITH FIRST AND * SECOND-LINE TYROSINE KINASE INHIBITORS IN PATIENTS WITH CHRONIC MYELOID LEUKEMIA

Цель – оценка эффективности лечения ингибиторами тирозинкиназ 1-й и 2-й линий неселективной группы пациентов с хроническим миелолейкозом в реальной клинической практике по отдаленным результатам.Материал и методы. В научную оценку включены отдаленные результаты проспективного одноцентрового сравнительного клинического исследования с использованием неселективного принципа формирования групп из 116 исследуемых больных хроническим миелолейкозом в различных фазах, получающих ингибитор тирозинкиназ 1-го поколения иматиниб, и из 44 пациентов, находящихся на терапии ингибитором тирозинкиназ 2-го поколения нилотинибом. Анализировали показатели общей выживаемости, беспрогрессивной выживаемости за период с апреля 2005 по апрель 2013 ; медиана наблюдения составила 128 месяцев. Результаты. Медиана общей выживаемости 116 больных хроническим миелолейкозом, получающих терапию иматинибом, исчисляемая методом Каплана – Мейера, составила 120 месяцев. У 44 пациентов в ранней хронической фазе 5-летняя общая и беспрогрессивная выживаемость отмечена в 93,2% случаев, 8-летняя общая и беспрогрессивная выживаемость – 79,5%. У 44 пациентов в поздней хронической фазе 5-летняя общая и беспрогрессивная выживаемость была 95,5%, 8-летняя общая и беспрогрессивная выживаемость – 72,7%. У 28 больных в фазе акселерации 5-летняя общая выживаемость составила 78,6%, 8-летняя общая выживаемость – 46%. Медиана общей выживаемости пациентов, находящихся на лечении нилотинибом, не достигнута. В течение 78,6 месяца комплексного лечения препаратами общего цитостатического действия, ингибиторами тирозинкиназ 1-й (иматинибом) и 2-й (нилотинибом) линий общая выживаемость составила 100%. Заключение. Включение больных хроническим миелолейкозом с резистентностью к иматинибу (рецидивом заболевания) либо непереносимостью иматиниба в программу лечения хронического миелолейкоза на первом этапе препаратами общего цитостатического действия, затем ингибиторами тирозинкиназ 1-й и 2-й линий существенно увеличивает общую выживаемость больных в клинической практике.

Recommandations 2015 du France Intergroupe des Leucémies Myéloïdes Chroniques pour la gestion du risque d’événements cardiovasculaires sous nilotinib au cours de la leucémie myéloïde chronique

Tyrosine kinase inhibitors targeting the BCR-ABL oncoprotein represent an outstanding progress in chronic myeloid leukemia and long-term progression-free survival has become a reality for a majority of patients. However, tyrosine kinase inhibitors may at best chronicize rather than cure the disease thus current recommendation is to pursue treatment indefinitely. As a consequence, high quality treatment and care must integrate optimal disease control and treatment tolerability. Tyrosine kinase inhibitors have an overall favorable safety profile in clinical practice since most adverse events are mild to moderate in intensity. However, recent evidence has emerged that new generation tyrosine kinase inhibitors may sometimes damage vital organs and if not adequately managed, morbidity and mortality may increase. The 2nd generation tyrosine kinase inhibitor nilotinib is licensed for the treatment of chronic myeloid leukemia with resistance or intolerance to imatinib and newly diagnosed chronic phase-chronic myeloid leukemia. Nilotinib represents an important therapeutic option but it is associated with an increased risk of cardiovascular events. The purpose of this article by the France Intergroupe des Leucémies Myéloïdes Chroniques is to provide an overview of nilotinib efficacy and cardiovascular safety profile and to propose practical recommendations with the goal to minimize the risk and severity of cardiovascular events in nilotinib-treated patients.

Different response to imatinib and nilotinib in relationship with the time of administration

Here we describe a case of a young patient with chronic myeloid leukemia at low risk, according to the Sokal index. After cytoreduction with hydroxyurea, the patient started imatinib at standard dose (400 mg/day) obtaining a minor cytogenetic response (Ph+ 42.5%) after six months of treatment.Considering the low imatinib concentration evaluated with the blood level testing, we increased the dose of imatinib at 600 mg/day. After about 3 months treatment the patient presented a partial cytogenetic response (Ph+ 30%). Therefore he was considered suboptimal responder according to European LeukemiaNet (ELN) recommendations 2006. For this reason he switched to second generation tyrosine kinase inhibitor nilotinib, at dose 800 mg/die. After switching to nilotinib the patient reached complete cytogenic response and major molecular response, maintained until last molecular evaluation.This kind of patient shows a different response for imatinib and nilotinib, whereas nilotinib therapy has shown to be safe and efficacy.

Successful nilotinib therapy in a CML affected patient with A380T, P407S and V468A mutations, and a previous suboptimal cytogenetic response to imatinib

Imatinib mesylate (IM) has shown unprecedented effectiveness in the treatment of Chronic Myeloid Leukemia (CML) patients (pts) in the chronic phase of the disease. However, some pts fail to respond or lose their initial response to IM. The European LeukemiaNet (ELN) published recommendations designed to identify patients responding poorly to imatinib. Here we report a case of a suboptimal cytogenetic responder to IM who had a successful response to the second generation tyrosine kinase inhibitor nilotinib (NIL). According to the ELN criteria, CML pts on IM-therapy might show a suboptimal response either because of failure to achieve a CCyR by 12 months of therapy or because of lack of a MMR after 18 months. The prognostic value of these two types of responders might be very different.

0194: Prospective analysis of plasma cholesterol and triglycerides in patients (pts) with chronic phase (CP)-chronic myeloid leukemia (CML) during treatment with the 2nd generation tyrosine kinase inhibitor

Despite a well-recognized clinical benefit of the 2nd generation tyrosine kinase inhibitor nilotinib in patients with imatinib-resistant/-intolerant or newly diagnosed chronic myeloid leukemia, recent evidence suggests that nilotinib has a propensity to increase the risk of occlusive arterial events, especially in patients with pre-existing cardiovascular risk factors. Given the key role of lipids in cardiovascular diseases, we studied the plasma lipid profile and global cardiovascular risk prior to and during nilotinib therapy in a series of 27 patients in the setting of an observationalsingle-center study. Data from a minimum 1-year follow-up showed that nilotinib significantly increased total, low and highdensity lipoprotein cholesterol within 3 months. Consequently, the proportion of patients with non-optimal low density lipoprotein cholesterol increased from 48.1% to 88.9% by 12 months, leading to cholesterol-lowering drug intervention in 22.2% of patients. The proportion of patients with low levels of high density lipoprotein cholesterol decreased from 40.7% to 7.4% by 12 months. In contrast, a significant decrease in triglycerides was observed. Global cardiovascular risk worsened in 11.1% of patients due to diabetes or occlusive arterial events. Whether hypercholesterolemia was the main driver of occlusive arterial events was uncertain: a longer follow-up is necessary to ask whether nilotinib-induced hypercholesterolemia increaseslong-term risk of atherosclerotic diseases. Nevertheless, given keyatherogenicproperties of low density lipoprotein cholesterol, we conclude that when prescribing nilotinib, commitment to detect lipid disordersat baseline and during follow-up is mandatory given their frequency, requirement for lifestyle or drug intervention and potential for long-term cardiovascular complications.

Increased Risk of Cardiovascular Events Associated with TKI Treatment in Chronic Phase Chronic Myeloid Leukemia. Data from Swedish Population-Based Registries

Introduction: The introduction of continuous tyrosine kinase inhibitor (TKI) treatment has dramatically improved progression-free survival for chronic phase chronic myeloid leukaemia (CML) patients. This success, however, has put the issue of long-term drug toxicity and safety into focus. Recent data from clinical studies have indicated an increased risk of cardiovascular events (CVE), including peripheral arterial occlusive disease, in CML patients receiving treatment with the TKIs nilotinib or ponatinib, as compared to imatinib (Giles et al, Leukemia 2013; Kim et al, Leukemia 2013; Cortes et al, New England Journal of Medicine 2013; FDA communication 2013).This study used data retrieved from Swedish population-based registries to estimate the frequency of CVE in CML patients, particularly those treated with imatinib and the 2nd generation TKIs nilotinib and dasatinib.Methods: We identified all incident cases between 2002 and 2012 in the Nationwide Swedish CML register. All patients who were in blast crisis or accelerated phase at time of diagnosis were excluded. All patients were followed untill death, emigration or 31st December 2012. For all CML patients a comparison cohort was established, matched to be of the same age and sex as the CML cohort, with 5 control subjects per CML patient. By means of record linkage with the nationwide Swedish patient register both cohorts were followed for the occurrence of adverse cardiovascular outcomes. Two sets of relative risks (expressed as incidence rate ratios; IRRs) of cardiovascular and venous thromboembolic disease were computed. In a first step CML patients were compared to the control population. In a second step, restricted to CML patients ever treated with TKIs, CML patients on different TKI treatments were compared. Patients could be treated with several TKIs during their follow-up, and events would only be attributable to the TKI used during the time period. Both analyses were adjusted for age, sex and calendar period. The second analysis was also adjusted for Sokal risk score.Results: A total of 896 CML patients were included and followed during a median of 4.2 years (Table I). The main outcome data are presented in Table II. A total of 23 venous thrombotic events (VTE) and 60 arterial thrombotic events were detected in the CML patient cohort during follow-up. Compared with the general population, this corresponded to significantly increased risks. In particular, deep venous thrombosis and “other arterial thromboses” were more common among CML patients (IRR 2.41 95% CI 1.29-4.52 and IRR 3.50 95% CI 1.36-9.04, respectively). Assessing risks associated with particular TKIs, we noted that treatment with any of the 2nd generation TKIs nilotinib or dasatinib, as compared to imatinib, was associated with a significantly increased occurrence of myocardial infarction (IRR 2.98 95% CI 1.05-8.49 and IRR 2.89 95% CI 1.20-7.00, respectively). Notably, there were no differences in the occurrence of CVE between the different patient groups before CML diagnosis.Conclusion: These data, derived from a large population-based Swedish cohort, provide evidence of an increased risk of both venous and arterial thrombotic events among CML patients and that patients on 2nd generation TKIs, as compared to imatinib, may be at increased risk of myocardial infarction. Further analyses will assess whether these differences may reflect patient selection and characterstics, rather than drug-related factors. Meanwhile, risk factors for CVE should be observed and considered in the TKI treatment of CML. [Display omitted] [Display omitted] * Footnote: the number of events may not add up because of occurrence of more than one type of vascular event in one subject. The number of events in the analysis within the CML cohort is lower than in the comparison with the general population because of exclusion of patients who were never treated with TKIs in the former analysis. DisclosuresBjörkholm:Novartis: Research Funding; Shire: Research Funding; Merck: Research Funding; Amgen: Honoraria, Research Funding; Pfizer: Research Funding; Bristol-Myers Squibb: Honoraria; Celgene: Honoraria; Akinon: Honoraria; Nordic Nanovector: Honoraria. Själander:Novartis: Honoraria. Richter:Ariad: Honoraria; Bristol-Myers Squibb: Honoraria; Novartis: Honoraria.

Early onset hypercholesterolemia induced by the 2nd-generation tyrosine kinase inhibitor nilotinib in patients with chronic phase-chronic myeloid leukemia

Despite a well-recognized clinical benefit of the 2(nd)-generation tyrosine kinase inhibitor nilotinib in patients with imatinib-resistant/-intolerant or newly diagnosed chronic myeloid leukemia, recent evidence suggests that nilotinib has a propensity to increase the risk of occlusive arterial events, especially in patients with pre-existing cardiovascular risk factors. Given the key role of lipids in cardiovascular diseases, we studied the plasma lipid profile and global cardiovascular risk prior to and during nilotinib therapy in a series of 27 patients in the setting of a prospective single center study. Data from a minimum 1-year follow up showed that nilotinib significantly increased total, low- and high-density lipoprotein cholesterol within three months. Consequently, the proportion of patients with non-optimal low-density lipoprotein cholesterol increased from 48.1% to 88.9% by 12 months, leading to cholesterol-lowering drug intervention in 22.2% of patients. The proportion of patients with low levels of high-density lipoprotein cholesterol decreased from 40.7% to 7.4% by 12 months. In contrast, a significant decrease in triglycerides was observed. Global cardiovascular risk worsened in 11.1% of patients due to diabetes or occlusive arterial events. Whether hypercholesterolemia was the main driver of occlusive arterial events was uncertain: a longer follow up is necessary to ask whether nilotinib-induced hypercholesterolemia increases long-term risk of atherosclerotic diseases. Nevertheless, given key atherogenic properties of low-density lipoprotein cholesterol, we conclude that when prescribing nilotinib, commitment to detect lipid disorders at baseline and during follow up is mandatory given their frequency, requirement for changes in lifestyle or drug intervention, and potential for long-term cardiovascular complications.

MicroRNA Dysregulation in Newly Diagnosed Chronic Myeloid Leukaemia Patients

IntroductionHeterogeneity within the CML patient population is evidenced by variable response dynamics and tolerability between patients treated with tyrosine kinase inhibitors (TKIs). Clinical risk scores have utility however do not inform upon the biology underpinning differential response. OCT1 activity has been established as a predictor of imatinib response but is not predictive for second generation TKIs nilotinib or dasatinib.In CML, microRNAs (miRNAs) have been implicated in BCR-ABL mediated signalling pathways and alter rapidly after TKI treatment. Indeed, we have previously established that miR-142-3p decreases within 14 days of TKI initiation and correlates with the SOKAL score. MethodWe performed miRNA profiling on 75 newly diagnosed, clinical trial CML patients (56% male, 44% female, median age 51 years) with greater than 24 months follow-up. RNA was extracted from peripheral blood mononuclear cells. The expression of 800 mature miRNA was analysed using the nCounter Human v2 miRNA Expression Assay (NanoString Technologies). In addition, IC50 values for imatinib and nilotinib were determined on all samples as previously described. ResultsThe miRNA expression levels obtained on this platform showed a wide dynamic range and substantial interpatient variation. This included miRNA previously reported in CML in vitro and patient studies: interquartile ranges were 52414 to 121632 for miR-142-3p, 3120 to 15599 for miR-451a, 2658 to 12023 for miR-150, 828 to 1461 for miR-181a-5p. In addition, we were able to identify miRNAs that were associated with nilotinib IC50 and imatinib IC50. DiscussionThe current study highlights the variability evident at the miRNA level between newly diagnosed CML patients. It provides a rationale to further examine the role of miRNA in CML pathogenesis, TKI response and define patient heterogeneity from diagnosis. Disclosures:White:Novartis: Research Funding; BMS: Research Funding, Speakers Bureau; Ariad: Research Funding; CSL: Research Funding. Hughes:Novartis: Honoraria, Research Funding; BMS: Honoraria, Research Funding; ARIAD: Honoraria, Research Funding.

Molecular Predictors for the Response to Nilotinib Treatment After Acquired Imatinib Failure In Ph+ Chronic Myeloid Leukemia

AbstractAbstract 2283 Introduction:A switch to the 2nd generation tyrosine kinase inhibitor nilotinib has been proven to be effective in case of resistance or intolerance to imatinib for the majority of patients with Ph+ chronic myeloid leukemia (CML) in chronic phase (CP). Besides mutations in the BCR-ABL kinase domain and various BCR-ABL-independent mechanisms, e.g. clonal evolution and activation of pathways bypassing BCR-ABL, efficacy of imatinib and nilotinib are dependent on intracellular drug levels, which are influenced by the activity of the efflux transporter protein multidrug resistance 1 (MDR1). Cell culture data suggest overexpression of MDR1 as a cause of resistance to nilotinib (Mahon et al., Cancer Res 2008). Moreover, Dulucq et al. (Blood 2008) report the association of MDR1 single nucleotide polymorphisms (SNPs) with the chance to achieve major molecular response (MMR) on first-line imatinib therapy. Aim:In order to allow risk stratification, we sought to elucidate molecular markers, e.g. MDR1 gene expression, BCR-ABL transcript burden, BCR-ABL mutation status and common SNPs in the MDR1 gene regarding their potency to predict therapy-related endpoints, such as MMR, complete cytogenetic response (CCyR), and progression-free survival (PFS) during second line therapy with nilotinib in imatinib-resistant CML-CP patients. Patients and Methods:A cohort of 83 imatinib-resistant patients in chronic phase CML treated with nilotinib was investigated within the AMN107A2101 phase I/II trial. Baseline BCR-ABL mutations were detected by D-HPLC and direct sequencing. MDR1 and BCR-ABL mRNA expression levels were determined by qRT-PCR using LightCycler™ technology, normalized against beta-glucuronidase (GUS) expression. BCR-ABL levels were standardized according to the international scale (IS). MDR1 SNPs (1236C>T, 2677G>T) were investigated using conventional sequencing. Log-rank tests were performed to compare the time to MMR (BCR-ABL IS ≤0.1%), CCyR, and PFS. Results:By 12 or 24 months, patients with MDR1/GUS ratios ≥2 achieved MMR in an estimated rate of 34%, CCyR was attained in rates of 53% and 58%, and PFS rates were 88% and 75%, whereas those with initial MDR1/GUS ratios <2 showed MMR in 13% (p=0.026), CCyR in 25% and 35% (p=0.028), and PFS in 71% and 50% (p=0.027), respectively (Table). Further, combining BCR-ABL load and MDR1 expression prior to nilotinib produced a significant association with subsequent molecular and cytogenetic response and PFS. By 12 or 24 months, patients presenting with BCR-ABL IS <13% and MDR1/GUS ≥2 showed MMR in 56%, CCyR in 75% and 81% and longer PFS in 93% and 85% compared to those with BCR-ABL IS ≥13% and MDR1/GUS <2 achieving MMR rates of 5% (p<0.001), CCyR rates of 26% and 38% (p=0.002) and PFS rates of 72% and 41%, respectively (p=0.013). Also, BCR-ABL kinase domain mutation status prior to the onset of nilotinib was significantly associated with PFS under nilotinib therapy: Patients without any mutation showed PFS rates of 90% and 71% at 12 or 24 months, respectively; whereas those harboring less sensitive or resistant mutations (Hughes et al., JCO 2009) attained only 26% PFS (p=0.028). Except for patients harboring less sensitive or resistant mutations there was no significant difference between unmutated and mutated patients. 31 of 39 patients revealed SNPs at the 1236 position and 33 of the 39 showed SNPs at the 2677 position. Nilotinib efficacy was not affected by MDR1 SNPs. Neither an association with the molecular outcome nor MDR1 gene expression under nilotinib therapy was found. Conclusions:The rates of MMR, CCyR, and PFS on nilotinib 2nd line therapy are significantly associated with baseline levels of MDR1 gene expression and tumor burden of imatinib-resistant CML-CP patients. Further, baseline BCR-ABL mutations predict the probability of PFS rates but do not seem to do so for MMR and CCyR. These findings might deliver new molecular tools for the clinical risk stratification for treatment with nilotinib in case of resistance under imatinib front line therapy and suggest the need for prospective validation.Table:MDR1/GUS ratio predictive for MMR, CCyR and PFSRatio MDR1/GUS dichotomized at 2pCutoff<2≥2MMR by 12 months13%34%0.026MMR by 24 months13%34%CCyR by 12 months25%53%0.028CCyR by 24 months35%58%PFS by 12 months71%88%0.027PFS by 24 months50%75% Disclosures:Reynolds: Novartis Oncology: Employment, Equity Ownership. Woodman: Novartis Oncology: Employment. Robin: Novartis Oncology: Employment. Hofmann: Novartis Oncology: Honoraria, Research Funding. Hochhaus: Novartis Oncology: Honoraria, Research Funding. Müller: Novartis Oncology: Honoraria, Research Funding.

The European Treatment and Outcome Study (EUTOS) for Chronic Myeloid Leukemia (CML). A Prospective, Population-Based European Registry.

Abstract 4272The incidence of Philadelphia positive (Ph+) chronic myeloid leukemia (CML) in Europe is still difficult to estimate, due to insufficient information. Currently, it is believed to range between 8 and 22 cases per million people per year, age adjusted. Prior to the introduction of the tyrosine kinase inhibitor (TKI) imatinib the annual death rate was about 10% for the first 2 to 3 years, and about 20% from the 4th year on, with less than 10% of patients alive after 10 years. Interferon-alfa treatment and allogeneic hematopoietic stem cell transplantation were very effective treatments but only in a minority of patients. Following the introduction of IM, and of the second generation TKI nilotinib and dasatinib the annual death rate has decreased to less than 5%, and more than 75% of patients are projected to be alive 10 years after diagnosis. Based on these figures, the prevalence of the disease is expected to double every 5 years and the management of the disease will rapidly become an important social and pharmacoeconomic issue. To govern this progress it is necessary to improve the level of information on the epidemiology of CML, on the treatment of CML in clinical practice, and on the outcome of treatment outside prospective, controlled clinical trials on which current outcome estimates are based. With that purpose, the European Leukemia Network (ELN) has established a registry of all new cases of Ph+ CML. In a public private partnership with Novartis Oncology Europe this registry has been expanded to also include treatment and quality controlled outcome (European Treatment and Outcome Study [EUTOS] for CML). The infrastructure of the registry is based on a EUTOS Central Scientific Headquarter (Dpt. Hematology-Oncology “L. and A. Seràgnoli”, University of Bologna, S.Orsola-Malpighi Hospital, Bologna, Italy) and a EUTOS Central Data Center (Dpt. For Medical Informatics, Biometric and Epidemiology, University of Munich, Munich, Germany), interacting with each national hub. Registry is population-based, covers completely most European countries with less than 12 millions inhabitants (Portugal, Belgium, Sweden, Finland, Lithuania, Latvia, Estonia, Czech Republic, Slovakia, Slovenia, Croatia, Serbia, Hungary, Austria, Greece, Cyprus), and covers partially (for larger countries, only sub-regions with roughly 10 millions inhabitants have been selected) most of the countries with more than 12 millions inhabitants, including Spain, the United Kingdom, The Netherlands, Germany, Poland, France, Romania, Russia and Italy. About 2500 newly diagnosed cases are planned to be registered over one year and to be followed for treatment and outcome including cytogenetic response, molecular response, and BCR-ABL KD mutations. Moreover, flanking projects have been implemented in the EUTOS frame: a network of standardized laboratories across Europe, to provide a molecular monitoring with quality controlled data, a central facility for imatinib blood level testing, soon in many European countries, and an educational effort (symposia, training workshops, internet platform). The EUTOS registry joins epidemiological and outcome data: its implementation requires considerable efforts and resources, but in the long run CML could become a model for epidemiologi and management of other cancers. Disclosures:Hasford:Novartis Pharma: Research Funding.

Modelling BCR-ABL1 Dynamics in Patients with Chronic Myeloid Leukemia in Chronic Phase (CML-CP) during Frontline Therapy with High-Dose Imatinib, Nilotinib, or Dasatinib.

The tyrosine kinase inhibitor (TKI) imatinib at the standard dose of 400mg/d renders high complete cytogenetic response (CCyR) rates but complete molecular response (CMR, i.e. undetectable BCR-ABL1) occurs only in a small proportion of patients. Therapy with high-dose imatinib (i.e. 800mg/d) has been reported to render significantly higher rates of CMR. The second generation TKIs nilotinib and dasatinib exhibit 1- to 2-log higher potency against BCR-ABL1 kinase in vitro, are active against multiple imatinib-resistant ABL1 kinase domain mutations, and result in high response rates in patients after failure of imatinib therapy. Here, we investigate the dynamics of peripheral blood BCR-ABL1 transcript levels in patients with CML-CP while receiving frontline therapy with highdose imatinib, nilotinib, or dasatinib. A total of 123 patients were investigated. Only timepoints 0, 3, 6, 9, 12, 18, and 24 months were analyzed. To be included in the analysis, patients had to have BCR-ABL1 levels available at least at 0, 3, 6, 9, and 12 months. Our goal was to develop a statistical model for these data depending on at most two subject-specific parameters, since there were typically only 5 to 7 time points per patient (median follow-up for the high-dose imatinib, nilotinib, and dasatinib groups was 48, 13, and 24 months, respectively). As a first step we used the cube root to transform our data, since the measurements are on vastly different scales and some of the observed values are zero. Our initial model on the transformed data was biexponential, which is the sum of two exponentials. We found that one of the exponentials could be replaced with a constant, which saved a parameter with little reduction in the fit. Our resulting model for the ith subject at time t is yi (t)= α0i + α1i exp[–βt], where α0i is the subject-specific intercept, α1i is the subject-specific slope, and β is the population-based shape parameter. A different version of the model is fit to each treatment group. We estimate beta (the shape parameter), after merging all data from a treatment group, using non-linear least squares. With beta fixed, we estimate the subject-specific parameters using traditional least squares. This model fits the data well, with a median R2 greater than 0.9 for all treatment groups. In a three-way comparison among nilotinib (n=23), dasatinib (n=24), and highdose imatinib (n=76), the most different population curves were between nilotinib and dasatinib (p=0.005). The nilotinib curve was also significantly different than the high-dose imatinib curve (p=0.04), while the curves for dasatinib and highdose imatinib were not significantly different (p=0.11). Nilotinib had a sharper earlier decline than dasatinib (beta=0.71 for nilotinib and beta=0.33 dasatinib), and high-dose imatinib was intermediate between the two (beta=0.44 for imatinib). We are currently examining whether there is a relationship between the subject-specific slopes and intercepts and other covariates, such as survival. We are also analyzing the implications of different shaped population curves for the different treatments.

The Initial Molecular Response of Chronic Phase CML Patients Treated with Second Generation ABL Inhibitor Therapy after Imatinib Failure Can Predict Inadequate Response and Provide Indications for Rational Mutation Screening

Molecular analysis is recommended for monitoring patients (pts) with CML. For imatinib treated pts in chronic phase (CP), molecular analysis provides important prognostic information. A major molecular response (MMR, BCR-ABL ≤0.1% IS (international scale)) is associated with favourable progression free survival and is a primary endpoint of clinical trials. The 3 month (m) BCR-ABL level is predictive of MMR and almost all de-novo pts with values ≤1.0% IS subsequently achieve MMR. The second generation tyrosine kinase inhibitors nilotinib and dasatinib (2TKI) have demonstrated efficacy for CP pts who fail imatinib therapy due to resistance or intolerance. However, treatment failure associated with the presence of a limited spectrum of resistant mutations is evident. Furthermore, it has recently been suggested that failure to achieve a major cytogenetic response (MCR) by 12m defines inadequate response and these pts should be considered for alternative therapies (Cortes et al, Blood , 2008, 112,516). Pts in minor cytogenetic response or complete hematologic response at 12m had a projected 1 year progression rate of 17% compared to 3% for those with MCR at 12m. The value of molecular monitoring in the setting of 2TKI has not been defined in terms of the early prediction of response or emergence of resistant mutations. We monitored BCR-ABL levels and mutation status in 155 CP pts treated with nilotinib (n=73; 400mg BD) or dasatinib (n=82; ≥100mg (76/82 70mg BD)) after imatinib failure for a median of 18m (range (r) 3–36). The BCR-ABL level at 3m of 2TKI was highly predictive of subsequent MMR, P<0.0001 (Figure A). Similarly, the 3m BCR-ABL level was highly predictive of MCR, P<0.0001 (Figure B). Among pts with BCR-ABL >10% IS, those who failed to achieve at least 50% at 3m had a significantly lower probability of MCR compared to those between 10–50%: 11% vs 56% by 24m, P=0.003. These analyses were also performed for pts with mutations at baseline (72/155, 46%) and for those without baseline mutations (83/155, 54%). The MMR and MCR rates based on the 3m BCR-ABL were still highly significant irrespective of the baseline mutation status, P<0.0001. We investigated factors associated with emergence of new mutations that have demonstrated a degree of resistance to 2TKI (2TKI resistant): T315I/A, F317L/I/V, V299L for dasatinib and T315I, Y253H, E255K/V, F359V/C (IC50 >150nM) for nilotinib. All pts with new mutations during dasatinib therapy (19/82, 23%) had one of the dasatinib 2TKI resistant mutations: T315I 9, F317L/I 6, V299L 4 pts. Mutations emerged in 15/73 (21%) nilotinib treated pts and were nilotinib 2TKI resistant in 11 pts (15%): T315I 5, F359V 4, Y253H 4, E255V 1 (2 pts had multiple mutations). 2TKI resistant mutations were detected at a median of 6m (r 1–24) and were more frequent in pts who already had a mutation at baseline compared to those without: 24/72 (33%) vs 6/83 (7%), P<0.0001. At the time of last molecular analysis 18 of 30 pts with new 2TKI resistant mutations had progressed, 7 had not progressed and the outcome was unknown for 5. Among pts with baseline mutations, the 3m BCR-ABL did not predict the emergence of 2TKI resistant mutations by 24m. Conversely, for pts without a baseline mutation the 3m BCR-ABL was predictive of emergent 2TKI resistant mutations when pts were divided into 2 groups: 1/53 pts (2%) ≤10% IS vs 5/30 pts (17%) >10% IS, P=0.02. In 16/30 pts (53%) with emergent 2TKI resistant mutations, BCR-ABL never fell below 10% IS. The rise in BCR-ABL associated with emergent mutations was minimal in these pts: median 2.2-fold and 6 pts had no change in BCR-ABL from baseline. This is a reflection of minimal response to 2TKI and hence minimal BCR-ABL reduction in these pts. The outcome is known for 13 of the 16 pts and 11/13 progressed. Regular mutation screening would be warranted in all pts with BCR-ABL >10% IS rather than upon a significant rise. The rise associated with emergent mutations when BCR-ABL was ≤10% IS was significantly higher: median 7.3-fold, P<0.0001. This degree of rise should be readily detected by serial analysis and would trigger mutation screening. In conclusion, BCR-ABL measured at 3m of 2TKI could predict response and for pts without baseline mutations it could predict the emergence of new mutations. All pts with BCR-ABL >10% IS are at risk of acquiring 2TKI resistant mutations and would benefit from regular mutation screening until BCR-ABL falls below 10% IS. Thereafter, a significant rise of >5-fold in BCR-ABL should trigger mutation screening. [Display omitted]

Therapeutic options against BCR-ABL1 T315I-positive chronic myelogenous leukemia.

Despite the efficacy of imatinib therapy in chronic myelogenous leukemia, the development of resistance continues to challenge the treatment of this disease. Mutations within the kinase domain of BCR-ABL1 constitute the most frequent mechanism of resistance in patients with chronic myelogenous leukemia treated with imatinib or the second generation tyrosine kinase inhibitors nilotinib and dasatinib. Of particular concern is the substitution of the threonine residue at the highly conserved gatekeeper residue 315 with a bulkier hydrophobic isoleucine amino acid. This mutation causes steric hindrance precluding the access ATP-competitive inhibitors to the ATP-binding pocket. To expedite the identification of strategies to override the resistance imposed by the T315I mutation, several strategies have been pursued, including the exploitation of BCR-ABL1 kinase sites distant from the ATP-binding pocket to cripple the kinase activity of the enzyme and inhibiting signaling pathways downstream from BCR-ABL1. Recent insights gained regarding the structural biology of T315I have led to the development of a variety of compounds against this mutant. We herein summarize the most clinically promising anti-T315I therapies.

Characterisation of Nilotinib Transport in Chronic Myeloid Leukaemia Cells.

We have previously shown that imatinib is a substrate for both the efflux transporter P-glycoprotein (ABCB1; MDR-1 gene product) and the influx transporter human Organic Cation Transporter 1 (hOCT1; SLCA22). High hOCT1 and low ABCB1 expression levels in chronic myeloid leukaemia (CML) patients correlate with improved clinical outcome (Wang L. et al. Clinical Pharmacology and Therapeutics; epub June 13th 2007). The second generation tyrosine kinase inhibitor nilotinib is 30-fold more potent than imatinib and is effective in imatinib-resistant patients. However, its cellular transport has not been characterised. The CML cell line KCL22 was used as it has low basal hOCT1 expression. Drug transport studies of 14C-radiolabelled nilotinib (kind gift from Novartis) were performed using high expressing hOCT1 transfected KCL22 cells, with or without OCT1 and ABCB1 inhibitors. Further vectorial ABCB1 efflux studies were performed on confluent monolayers of ABCB1 transfected Type II Madin Darby canine kidney (MDCKII) cells. Nilotinib efflux was not modulated in the presence of the ABCB1 inhibitors PSC-833 (10μM), tariquidar (500nM) and verapamil (500μM), and no evidence of transport via ABCB1 was seen in the transfected ABCB1 MDCKII cells. Nilotinib influx was not modulated in hOCT1 over-expressing cells, or in the presence of OCT1 inhibitors prazosin (100μM) and amantadine (500μM). Nilotinib uptake was also not modulated by the hOCT1 substrate tetraethylamine (TEA) (5μM), however nilotinib inhibited TEA uptake. The distribution coefficient (logD) of nilotinib was 2.1, compared with 0.81 for imatinib, demonstrating high lipophilicity for nilotinib. Flow cytometry revealed greater suppression of phospho-CrKL (a surrogate marker for BCR-ABL blockade) with nilotinib after 1 hour when compared with imatinib, regardless of hOCT1 expression, indicating that nilotinib is effective at BCR-ABL suppression even at low hOCT1 levels, in contrast to imatinib. Nilotinib was not a substrate for the ABCB1 and hOCT1 transporters; however it may be a potential inhibitor of hOCT1. Therefore the level of expression of ABCB1 and hOCT1 in CML is unlikely to be an indicator of the clinical outcome for patients receiving nilotinib, in contrast to what we have shown for imatinib. Nilotinib may therefore be effective in patients who have low hOCT1 expression before start of therapy.