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1.
Lancet Oncol ; 22(10): 1468-1482, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34592180

RESUMO

BACKGROUND: Biliary tract cancers are aggressive, rare, gastrointestinal malignancies with a poor prognosis; approximately half of patients with these cancers survive for less than 1 year after diagnosis with advanced disease. We aimed to evaluate the efficacy and safety of ramucirumab or merestinib in addition to first-line cisplatin-gemcitabine in patients with locally advanced or metastatic biliary tract cancer. METHODS: We did a randomised, double-blind, phase 2 study at 81 hospitals across 18 countries. We enrolled patients with histologically or cytologically confirmed, non-resectable, recurrent, or metastatic biliary tract adenocarcinoma, who were treatment-naive, aged 18 years or older, with an Eastern Cooperative Oncology Group performance status of 0 or 1, estimated life expectancy of 3 months or more, and measurable disease per Response Evaluation Criteria in Solid Tumors version 1.1. Eligible participants were randomly assigned (2:1:2:1) to receive either intravenous ramucirumab 8 mg/kg or placebo (on days 1 and 8 in 21-day cycles) or oral merestinib 80 mg or placebo (once daily) until disease progression, unacceptable toxicity, death, or patient or investigator request for discontinuation. All participants received intravenous cisplatin 25 mg/m2 and gemcitabine 1000 mg/m2 (on days 1 and 8 in 21-day cycles), for a maximum of eight cycles. Randomisation was done by an interactive web response system using a permuted block method (blocks of six) and was stratified by primary tumour site, geographical region, and presence of metastatic disease. Participants, investigators, and the study funder were masked to treatment assignment within the intravenous and oral groups. The primary endpoint was investigator-assessed progression-free survival (in the intention-to-treat population). The safety analysis was done in all patients who received at least one dose of their assigned treatment. This trial is registered with ClinicalTrials.gov, NCT02711553, and long-term follow-up is ongoing. FINDINGS: Between May 25, 2016, and Aug 8, 2017, 450 patients were assessed for eligibility and 309 (69%) were enrolled and randomly assigned to ramucirumab (n=106), merestinib (n=102), or pooled placebo (n=101); 306 received at least one dose of study treatment. The median follow-up time for progression-free survival at data cutoff (Feb 16, 2018) was 10·9 months (IQR 8·1-14·1). Median progression-free survival was 6·5 months (80% CI 5·7-7·1) in the ramucirumab group, 7·0 months (6·2-7·1) in the merestinib group, and 6·6 months (5·6-6·8) in the pooled placebo group (ramucirumab vs placebo hazard ratio 1·12 [80% CI 0·90-1·40], two-sided stratified p=0·48; merestinib vs placebo 0·92 [0·73-1·15], two-sided stratified p=0·64). The most common grade 3 or worse adverse events were neutropenia (51 [49%] of 104 patients in the ramucirumab group; 48 [47%] of 102 in the merestinib group; and 33 [33%] of 100 in the pooled placebo group), thrombocytopenia (36 [35%]; 19 [19%]; and 17 [17%]), and anaemia (28 [27%]; 16 [16%]; and 19 [19%]). Serious adverse events occurred in 53 (51%) patients in the ramucirumab group, 56 (55%) in the merestinib group, and 48 (48%) in the pooled placebo group. Treatment-related deaths (deemed related by the investigator) occurred in one (1%) of 104 patients in the ramucirumab group (cardiac arrest) and two (2%) of 102 patients in the merestinib group (pulmonary embolism [n=1] and sepsis [n=1]). INTERPRETATION: Adding ramucirumab or merestinib to first-line cisplatin-gemcitabine was well tolerated, with no new safety signals, but neither improved progression-free survival in patients with molecularly unselected, locally advanced or metastatic biliary tract cancer. The role of these targeted inhibitors remains investigational, highlighting the need for further understanding of biliary tract malignancies and the contribution of molecular selection. FUNDING: Eli Lilly and Company.


Assuntos
Adenocarcinoma/tratamento farmacológico , Inibidores da Angiogênese/administração & dosagem , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias do Sistema Biliar/tratamento farmacológico , Indazóis/administração & dosagem , Niacinamida/análogos & derivados , Inibidores de Proteínas Quinases/administração & dosagem , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Idoso , Inibidores da Angiogênese/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias do Sistema Biliar/mortalidade , Neoplasias do Sistema Biliar/patologia , Progressão da Doença , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Indazóis/efeitos adversos , Masculino , Pessoa de Meia-Idade , Niacinamida/administração & dosagem , Niacinamida/efeitos adversos , Intervalo Livre de Progressão , Inibidores de Proteínas Quinases/efeitos adversos , Fatores de Tempo , Ramucirumab
2.
Cephalalgia ; 40(9): 978-989, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32340471

RESUMO

BACKGROUND: This analysis characterizes the immunogenicity profile of galcanezumab, a humanized monoclonal antibody that selectively binds calcitonin gene-related peptide and inhibits its activity, in phase 3 migraine trials. METHODS: Immunogenicity data were analyzed from baseline and double-blind, placebo-controlled phases of the 3-month chronic migraine study REGAIN, the 6-month episodic migraine studies EVOLVE-1 and EVOLVE-2, and from baseline and open-label phases of the 12-month chronic and episodic migraine Study CGAJ. The incidence of baseline antidrug antibodies, treatment-emergent antidrug antibodies, neutralizing antidrug antibodies, and the effect of antidrug antibody titer on pharmacokinetics and pharmacodynamics were assessed. The relationship between antidrug antibody status and efficacy was explored using average change in monthly migraine headache days. Safety analyses assessed the potential relationship between treatment-emergent antidrug antibodies and hypersensitivity events or adverse events related to injection sites. FINDINGS: Across studies, 5.9-11.2% of patients had baseline antidrug antibodies. The incidence of treatment-emergent antidrug antibodies was 2.6-12.4% in the galcanezumab group and 0.5-1.7% in the placebo group. The majority of treatment-emergent antidrug antibodies were detected approximately 3-6 months after first study drug dose. Overall, the observed antidrug antibody titer did not impact galcanezumab concentrations, calcitonin gene-related peptide concentrations, or galcanezumab efficacy. There was no evidence that hypersensitivity events or adverse events related to injection sites were mediated by treatment-emergent antidrug antibodies. INTERPRETATION: These data showed that immunogenicity did not impact galcanezumab concentrations, calcitonin gene-related peptide concentrations, or the efficacy and hypersensitivity profile of galcanezumab in patients with migraine.


Assuntos
Anticorpos Monoclonais Humanizados/imunologia , Transtornos de Enxaqueca/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Peptídeo Relacionado com Gene de Calcitonina/antagonistas & inibidores , Ensaios Clínicos Fase III como Assunto , Humanos
3.
Invest New Drugs ; 33(3): 710-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25902900

RESUMO

The primary objective of this phase I study of LY2780301, a dual p70 S6 kinase and Akt inhibitor, was to determine the recommended phase II dose as a single agent in patients with advanced cancer. Secondary objectives included safety, pharmacokinetic, and pharmacodynamic analyses, and co-clinical analyses in Avatar models. Eligible patients received total daily doses of LY2780301 100-500 mg, given orally as a single dose or divided into 2 doses for 28-day cycles. Dose escalation followed 3 + 3 design. The primary pharmacodynamic endpoint was inhibition of S6 assessed by skin and tumor biopsy. Thirty-two patients were treated. Common toxicities possibly related to treatment included constipation (19 %), fatigue (13 %), nausea (9 %), and diarrhea (9 %). Grade 3/4 toxicities potentially related to treatment were anemia (n = 2), increased alanine aminotransferase/aspartate aminotransferase (ALT) (n = 1), and increased gamma-glutamyl transpeptidase (GGT) (n = 1). One patient experienced best overall response of prolonged stable disease for 6 cycles. Plasma exposures of LY2780301 exceeded predicted efficacious exposures, but were not dose proportional. Among patients receiving 500 mg daily >50 % exhibited reduced S6 in skin biopsies at Day 8 of treatment, but the effect was not maintained. Plasma concentrations of LY2780301 and/or its metabolites were not correlated with S6 expression in the epidermis. There was minimal antitumor activity against the model, CRC 019. Avatar models showed minimal pharmacodynamic effects consistent with the observed antitumor effects. This study suggests a dose of LY2780301 500 mg QD for future studies.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Quinases S6 Ribossômicas 70-kDa/antagonistas & inibidores , Adulto , Idoso , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Feminino , Humanos , Masculino , Camundongos Nus , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias/enzimologia , Neoplasias/patologia , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/farmacocinética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto Jovem
4.
J Pediatr Hematol Oncol ; 37(1): 1-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25493452

RESUMO

INTRODUCTION: This phase 2 study was designed to characterize the relationship among prasugrel dose, prasugrel's active metabolite (Pras-AM), and platelet inhibition while evaluating safety in children with sickle cell disease. It was open-label, multicenter, adaptive design, dose ranging, and conducted in 2 parts. Part A: Patients received escalating single doses leading to corresponding increases in Pras-AM exposure and VerifyNow®P2Y12 (VN) platelet inhibition and decreases in VNP2Y12 reaction units and vasodilator-stimulated phosphoprotein platelet reactivity index. Part B: Patients were assigned daily doses (0.06, 0.08, and 0.12 mg/kg) based on VN pharmacodynamic measurements at the start of 2 dosing periods, each 14±4 days. Platelet inhibition was significantly higher at 0.12 mg/kg (56.3%±7.4%; least squares mean±SE) compared with 0.06 mg/kg (33.8%±7.4%) or 0.08 mg/kg (37.9%±5.6%). Patients receiving 0.12 mg/kg achieved ≥30% platelet inhibition; only 1 patient receiving 0.06 mg/kg exceeded 60% platelet inhibition. High interpatient variability in response to prasugrel and the small range of exposures precluded rigorous characterization of the relationship among dose, Pras-AM, and platelet inhibition. SAFETY: No hemorrhagic events occurred in Part A; 3 occurred in Part B, all mild and self-limited. CONCLUSIONS: Most children with sickle cell disease may achieve clinically relevant platelet inhibition with titration of daily-dose prasugrel.


Assuntos
Anemia Falciforme/tratamento farmacológico , Piperazinas/farmacologia , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Tiofenos/farmacologia , Adolescente , Anemia Falciforme/sangue , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Modelos Biológicos , Piperazinas/efeitos adversos , Piperazinas/farmacocinética , Inibidores da Agregação Plaquetária/farmacologia , Cloridrato de Prasugrel , Antagonistas do Receptor Purinérgico P2Y/farmacocinética , Projetos de Pesquisa , Tiofenos/efeitos adversos , Tiofenos/farmacocinética
5.
J Thromb Thrombolysis ; 38(2): 127-36, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24043374

RESUMO

Body weight is a predictor of clopidogrel response. However, no prospective studies have compared pharmacodynamic (PD) and pharmacokinetic (PK) data based on body weight. We compared PD and PK effects of clopidogrel 75 mg in low body weight (LBW, <60 kg) and higher body weight (HBW, ≥60 kg) patients with stable coronary artery disease. LBW (n = 34, 56.4 ± 3.7 kg) and HBW (n = 38, 84.7 ± 14.9 kg) aspirin-treated patients received clopidogrel 75 mg for 10-14 days. The area under the concentration-time curve of active metabolite (Clop-AM) calculated through the last quantifiable concentration up to 4 h postdose, AUC(0-tlast), was calculated by noncompartmental methods. Light transmission aggregometry (LTA) (maximum platelet aggregation and inhibition of platelet aggregation to 20 µM adenosine diphosphate (ADP), and residual platelet aggregation to 5 µM ADP), VerifyNow(®) P2Y12 reaction units (PRU), and vasodilator-associated stimulated phosphoprotein phosphorylation platelet reactivity index (VASP-PRI) were performed. Mean AUC(0-tlast) was lower in HBW than LBW patients: 12.8 versus 17.9 ng h/mL. HBW patients had higher platelet reactivity as measured by LTA (all p ≤ 0.01), PRU (207 ± 68 vs. 152 ± 57, p < 0.001), and VASP-PRI (56 ± 18 vs. 39 ± 17, p < 0.001). More HBW patients exhibited high on-treatment platelet reactivity (HPR) using PRU (35 vs. 9%) and VASP-PRI (65 vs. 27%). Body weight correlated with PRU and VASP-PRI (both p < 0.001), and inversely with log transformed AUC(0-tlast) (p < 0.001). In conclusion, HBW patients had lower levels of Clop-AM, and higher platelet reactivity and rates of HPR than LBW subjects, contributing to their suboptimal response to clopidogrel.


Assuntos
Peso Corporal , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/farmacocinética , Ticlopidina/análogos & derivados , Adolescente , Adulto , Idoso , Plaquetas/metabolismo , Clopidogrel , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária/efeitos dos fármacos , Ticlopidina/administração & dosagem , Ticlopidina/farmacocinética
6.
Clin Cancer Res ; 25(17): 5202-5211, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31142504

RESUMO

PURPOSE: Inhibition of the VEGFR-2 blocks angiogenesis and attenuates tumor growth, but cancers may evade this effect through activation of the hepatocyte growth factor receptor MET. Here we report results of the phase Ib/II study of ramucirumab, a monoclonal anti-VEGFR-2 antibody, plus the anti-MET mAb emibetuzumab. PATIENTS AND METHODS: A 3+3 dose escalation of emibetuzumab plus ramucirumab (phase Ib) was followed by tumor-specific expansion cohorts. Primary objectives were to determine the recommended phase II dose and to evaluate antitumor activity. Secondary objectives included safety, pharmacokinetics, and immunogenicity. Tumoral MET expression was explored by immunohistochemistry (IHC). RESULTS: A total of 97 patients with solid tumor [6 phase Ib, 16 gastric or gastroesophageal junction adenocarcinoma, 45 hepatocellular carcinoma (HCC), 15 renal cell carcinoma, and 15 non-small lung cancer] received emibetuzumab at 750 or 2,000 mg flat dosing plus ramucirumab at 8 mg/kg every 2 weeks. No dose-limiting toxicities were observed. Common adverse events were primarily mild or moderate and included fatigue (36.1%), peripheral edema (28.9%), and nausea (14.4%). Emibetuzumab exposures were similar as in previous studies with no apparent drug-drug interactions. Five partial responses (5.2%) were observed across all tumor types. The greatest antitumor activity was noted in HCC with a 6.7% overall response rate, 60% disease control rate, and 5.42 months (95% confidence interval, 1.64-8.12) progression-free survival (PFS). HCC with high MET expression showed improved PFS with approximately 3-fold increase in PFS (8.1 vs. 2.8 months) relative to low MET expression. CONCLUSIONS: Ramucirumab plus emibetuzumab was safe and exhibited cytostatic antitumor activity. MET expression may help to select patients benefitting most from this combination treatment in select tumor types.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Antineoplásicos Imunológicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/imunologia , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Taxa de Sobrevida , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Adulto Jovem , Ramucirumab
7.
Clin Pharmacokinet ; 57(2): 243-254, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28578536

RESUMO

BACKGROUND AND OBJECTIVE: Prasugrel, a P2Y12 adenosine diphosphate (ADP) receptor antagonist, inhibits ADP-mediated platelet activation and aggregation in patients with sickle cell anemia (SCA). We developed a population pharmacokinetic (popPK) model in pediatric patients from 2 to <18 years of age with SCA, and performed exposure-response evaluations to characterize the effects of prasugrel in a subset of these patients who weighed 19 kg or more and experienced at least two episodes of vaso-occlusive crises (VOC) in the past year. METHODS: A three-compartment popPK model adapted from that used in adults with acute coronary syndrome was used to describe the relationship between plasma concentrations of prasugrel's active metabolite (Pras-AM) and time using data from phase II and III clinical studies in children. A VOC event rate model was developed from the phase III study to explore the exposure-response relationship between Pras-AM exposure and VOC, and included evaluation of covariates. RESULTS: The final popPK model for children with SCA provided a reasonable fit to Pras-AM plasma concentrations over time, with estimates of apparent clearance (CL/F) (172 L/h) and apparent volume of distribution (Vd/F) (51.7 L) that were comparable to previous studies in adults. The final model included weight as a covariate on both CL/F and Vd/F, and age as a covariate on CL/F. Analyses of safety (bleeding events requiring medical intervention) and efficacy (VOC event rate) variables showed no apparent relationship to model-predicted Pras-AM exposure quartiles, and no statistically significant effects of intrinsic or extrinsic factors on the VOC event rate were identified in the VOC event rate model. The effect of post hoc exposures on the VOC event rate did not reach statistical significance. CONCLUSIONS: A popPK model was developed that provided reasonable parameter estimates, goodness-of-fit diagnostics, and visual predictive checks when applied to Pras-AM plasma concentrations in pediatric patients with SCA. Post hoc exposures obtained from this model did not correlate with measures of VOC or bleeding events in this population.


Assuntos
Anemia Falciforme/tratamento farmacológico , Modelos Biológicos , Inibidores da Agregação Plaquetária/administração & dosagem , Cloridrato de Prasugrel/administração & dosagem , Adolescente , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Masculino , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Agregação Plaquetária/farmacocinética , Cloridrato de Prasugrel/efeitos adversos , Cloridrato de Prasugrel/farmacocinética , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Thromb Res ; 134(3): 552-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25022828

RESUMO

INTRODUCTION: Patients treated with clopidogrel who have higher body size exhibit greater platelet reactivity than patients with lower body size. In a retrospective analysis of the FEATHER trial, we examined the relationship between platelet response to thienopyridines clopidogrel 75 mg (Clop-75), prasugrel 5mg (Pras-5), and prasugrel 10mg (Pras-10) using 3 body size indices: body weight (BW), body mass index (BMI), and body surface area (BSA). Relationships were assessed as continuous variables and as 4 incremental body size groups. MATERIALS AND METHODS: Aspirin-treated patients with stable coronary artery disease (N=72) and a BW range of 45-134 kg received Clop-75, Pras-5, and Pras-10 in a 3-period, blinded, cross-over study. Platelet assays included maximum platelet aggregation (MPA) to 20µM ADP by light transmission aggregometry, VerifyNow-P2Y12 reaction units (PRU), and vasodilator-associated stimulated phosphoprotein (VASP) phosphorylation platelet reactivity index (PRI). Exposure to active metabolites (AMs) was also assessed. RESULTS: Body size was a determinant of AM exposure and residual platelet reactivity regardless of type and dose of thienopyridine. BW and BSA demonstrated marginally stronger correlations with platelet reactivity; VASP-PRI demonstrated a stronger correlation with the body size than the other tests. Correlation coefficients ranged from a high of 0.64 (BW vs. PRI on Pras-5) to a low of 0.34 (BMI vs. MPA on Pras-10), but all were statistically significant (p<0.01). CONCLUSIONS: Using a comprehensive selection of body size indices, AM exposures, platelet function tests, and thienopyridine doses, we demonstrated a consistent inverse relationship between body size and response to clopidogrel and prasugrel.


Assuntos
Plaquetas/efeitos dos fármacos , Tamanho Corporal , Doença da Artéria Coronariana/tratamento farmacológico , Cálculos da Dosagem de Medicamento , Inibidores da Agregação Plaquetária/farmacocinética , Cloridrato de Prasugrel/farmacocinética , Antagonistas do Receptor Purinérgico P2Y/farmacocinética , Ticlopidina/análogos & derivados , Adulto , Idoso , Biomarcadores/sangue , Plaquetas/metabolismo , Índice de Massa Corporal , Superfície Corporal , Peso Corporal , Moléculas de Adesão Celular/sangue , Clopidogrel , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico , Feminino , Humanos , Masculino , Proteínas dos Microfilamentos/sangue , Pessoa de Meia-Idade , Fosfoproteínas/sangue , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/administração & dosagem , Testes de Função Plaquetária , Cloridrato de Prasugrel/administração & dosagem , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Receptores Purinérgicos P2Y12/sangue , Receptores Purinérgicos P2Y12/efeitos dos fármacos , Estudos Retrospectivos , Ticlopidina/administração & dosagem , Ticlopidina/farmacocinética , Resultado do Tratamento
9.
Thromb Haemost ; 111(5): 943-50, 2014 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-24402637

RESUMO

We compared results obtained with the Nanosphere Verigene® System, a novel point-of-care (POC) genetic test capable of analysing 11 CYP2C19 variants within 3 hours, to an established, validated genotyping method (Affymetrix™ DMET+; reference assay) for identifying extensive and reduced metabolisers of clopidogrel. Based on genotyping, patients (N=82) with stable coronary artery disease on clopidogrel 75 mg daily were defined as extensive metabolisers (*1/*1, *1/*17, *17/*17), reduced metabolisers (*1/*2, *1/*8, *2/*2, *2/*3), or of indeterminate metaboliser status (*2/*17). Pharmacokinetic exposure to clopidogrel's active metabolite and pharmacodynamic measures with P2Y12 reaction units (PRU) (VerifyNow®P2Y12 assay) and VASP PRI (PRI) were also assessed. There was a 99.9% overall concordance of marker-level data between the Nanosphere Verigene and DMET+ systems in identifying the CYP2C19 variants and 100% agreement in classifying the patients as extensive (n=59) or reduced metabolisers (n=15). Extensive metabolisers had significantly higher active metabolite exposure than reduced metabolisers (LS means 12.6 ng*h/ml vs 7.7 ng*h/ml; p<0.001). Extensive metabolisers also had lower PRU (LS means 158 vs 212; p=0.003) and VASP PRI (LS means 48% vs 63%, p=0.01) compared to reduced metabolisers. Rates of high on-treatment platelet reactivity were higher in reduced metabolisers compared to extensive metabolisers (VASP PRI ≥ 50%: 79% vs 47%; PRU >235: 33% vs 16%). The Nanosphere Verigene CBS system identified 11 CYP2C19 alleles in less than 3 hours with a high degree of accuracy when compared to a conventional method, and was further validated against pharmacokinetic and pharmacodynamic phenotypes.


Assuntos
Doença da Artéria Coronariana/tratamento farmacológico , Citocromo P-450 CYP2C19/genética , Testes Genéticos/métodos , Ticlopidina/análogos & derivados , Adolescente , Idoso , Clopidogrel , Doença da Artéria Coronariana/genética , Feminino , Genótipo , Ensaios de Triagem em Larga Escala , Humanos , Inativação Metabólica/genética , Cooperação Internacional , Masculino , Pessoa de Meia-Idade , Sistemas Automatizados de Assistência Junto ao Leito , Polimorfismo Genético , Ticlopidina/farmacocinética , Ticlopidina/uso terapêutico , Resultado do Tratamento , Adulto Jovem
10.
J Am Coll Cardiol ; 64(10): 1005-14, 2014 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-25190236

RESUMO

BACKGROUND: Several studies have shown that patients with diabetes mellitus (DM) exhibit an impaired response to clopidogrel. This may contribute to their increased risk of recurrent atherothrombotic events, despite the use of dual-antiplatelet therapy. The mechanisms for impaired clopidogrel response in DM patients have not been fully elucidated. OBJECTIVES: The aim of this study was to explore the mechanisms for impaired clopidogrel-mediated platelet inhibition in patients with DM using a comprehensive methodological approach embracing both pharmacokinetic (PK) and pharmacodynamic (PD) assessments as well as ex vivo and in vitro investigations. METHODS: Patients (DM, n = 30; non-DM, n = 30) with stable coronary artery disease taking aspirin 81 mg/day and P2Y12 antagonist naive were enrolled. Blood was collected before and at various times (0.5, 1, 2, 4, 6, and 24 h) after a 600-mg loading dose of clopidogrel. PD assessments included vasodilator-stimulated phosphoprotein, light transmission aggregometry, and VerifyNow P2Y12 ex vivo, before and after dosing and following in vitro incubation with escalating concentrations (1, 3, and 10 µM) of clopidogrel's active metabolite (Clop-AM). Exposure to Clop-AM was also determined. RESULTS: PD assessments consistently showed that during the overall 24-h study time course, residual platelet reactivity was higher in DM patients compared with non-DM patients. In vitro incubation with Clop-AM revealed altered functional status of the P2Y12 signaling pathway in DM platelets as measured by vasodilator-stimulated phosphoprotein, but not with other PD assays. Clop-AM exposure was ∼40% lower in DM patients than in non-DM patients. CONCLUSIONS: The present study suggests that among DM patients, impaired P2Y12 inhibition mediated by clopidogrel is largely attributable to attenuation of clopidogrel's PK profile. This is characterized by lower plasma levels of Clop-AM over the sampling time course in DM patients compared with non-DM patients and only modestly attributed to altered functional status of the P2Y12 signaling pathway.


Assuntos
Doença da Artéria Coronariana/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Agregação Plaquetária/efeitos dos fármacos , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Ticlopidina/análogos & derivados , Adulto , Idoso , Aspirina/efeitos adversos , Aspirina/uso terapêutico , Clopidogrel , Estudos de Coortes , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/complicações , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Agregação Plaquetária/uso terapêutico , Testes de Função Plaquetária , Estudos Prospectivos , Antagonistas do Receptor Purinérgico P2Y/efeitos adversos , Valores de Referência , Medição de Risco , Ticlopidina/efeitos adversos , Ticlopidina/uso terapêutico , Resultado do Tratamento
11.
J Am Coll Cardiol ; 62(7): 577-83, 2013 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-23747759

RESUMO

OBJECTIVES: This study assessed pharmacodynamic (PD) response to the reduced prasugrel maintenance dose of 5 mg in very elderly (VE) patients (≥75 years of age). BACKGROUND: In the TRITON-TIMI 38 (TRial to Assess Improvement in Therapeutic Outcomes by Optimizing Platelet InhibitioN with Prasugrel-Thrombolysis In Myocardial Infarction 38) study prasugrel 10 mg reduced ischemic events versus clopidogrel 75 mg, but increased bleeding in VE patients. METHODS: We examined PD and active metabolite pharmacokinetics (PKs) with prasugrel 5 and 10 mg and clopidogrel 75 mg in a 3-period (12 days each) blinded, crossover study in VE (n = 73; mean: 79 ± 3 years of age) or (n = 82) nonelderly (NE) (≥45 to <65 years of age; mean: 56 ± 5 years of age) stable coronary artery disease (CAD) patients receiving background aspirin. Assays included light transmission aggregometry (LTA), VerifyNow P2Y12 (VN-P2Y12), and vasodilator-associated stimulated phosphoprotein (VASP). The primary comparison was noninferiority of maximum platelet aggregation (MPA) comparing the median for prasugrel 5 mg in VE versus the 75th percentile for prasugrel 10 mg in NE, using a pre-specified 1-sided 97.5% confidence interval for the difference <15%. RESULTS: Prasugrel 5 mg in VE met the primary PD noninferiority criterion versus prasugrel 10 mg in NE. For prasugrel 5 mg, MPA was significantly lower (57 ± 14%) than clopidogrel (63 ± 14%; p < 0.001) in VE but higher than prasugrel 10 mg in NE (46 ± 12%; p < 0.001). PD response by LTA, VN-P2Y12, and VASP during all treatments appeared similar between age cohorts. Prasugrel 5 mg resulted in fewer VE poor responders than clopidogrel. Rates of mild bleeding were higher with prasugrel 10 mg but similar for prasugrel 5 mg versus clopidogrel 75 mg. CONCLUSIONS: In aspirin-treated stable CAD patients, prasugrel 5 mg in VE attenuated platelet inhibition while meeting pre-specified noninferiority criterion versus prasugrel 10 mg in NE, with significantly better PD response and fewer poor responders compared to clopidogrel 75 mg in VE. (Comparison of Prasugrel and Clopidogrel in Very Elderly and Non-Elderly Patients With Stable Coronary Artery Disease [GENERATIONS]; NCT01107912).


Assuntos
Doença da Artéria Coronariana/tratamento farmacológico , Piperazinas/administração & dosagem , Piperazinas/farmacocinética , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/farmacocinética , Tiofenos/administração & dosagem , Tiofenos/farmacocinética , Administração Oral , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Clopidogrel , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Estudos Cross-Over , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Piperazinas/efeitos adversos , Inibidores da Agregação Plaquetária/efeitos adversos , Cloridrato de Prasugrel , Valores de Referência , Índice de Gravidade de Doença , Método Simples-Cego , Taxa de Sobrevida , Tiofenos/efeitos adversos , Ticlopidina/administração & dosagem , Ticlopidina/efeitos adversos , Ticlopidina/análogos & derivados , Ticlopidina/farmacocinética , Resultado do Tratamento
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