Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 96
Filtrar
1.
Nature ; 615(7953): 678-686, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36922586

RESUMO

Dengue is a major health threat and the number of symptomatic infections caused by the four dengue serotypes is estimated to be 96 million1 with annually around 10,000 deaths2. However, no antiviral drugs are available for the treatment or prophylaxis of dengue. We recently described the interaction between non-structural proteins NS3 and NS4B as a promising target for the development of pan-serotype dengue virus (DENV) inhibitors3. Here we present JNJ-1802-a highly potent DENV inhibitor that blocks the NS3-NS4B interaction within the viral replication complex. JNJ-1802 exerts picomolar to low nanomolar in vitro antiviral activity, a high barrier to resistance and potent in vivo efficacy in mice against infection with any of the four DENV serotypes. Finally, we demonstrate that the small-molecule inhibitor JNJ-1802 is highly effective against viral infection with DENV-1 or DENV-2 in non-human primates. JNJ-1802 has successfully completed a phase I first-in-human clinical study in healthy volunteers and was found to be safe and well tolerated4. These findings support the further clinical development of JNJ-1802, a first-in-class antiviral agent against dengue, which is now progressing in clinical studies for the prevention and treatment of dengue.


Assuntos
Antivirais , Vírus da Dengue , Dengue , Primatas , Proteínas não Estruturais Virais , Animais , Humanos , Camundongos , Antivirais/efeitos adversos , Antivirais/farmacologia , Antivirais/uso terapêutico , Ensaios Clínicos Fase I como Assunto , Dengue/tratamento farmacológico , Dengue/prevenção & controle , Dengue/virologia , Vírus da Dengue/classificação , Vírus da Dengue/efeitos dos fármacos , Relação Dose-Resposta a Droga , Farmacorresistência Viral , Técnicas In Vitro , Terapia de Alvo Molecular , Primatas/virologia , Ligação Proteica/efeitos dos fármacos , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo , Replicação Viral
2.
Eur J Epidemiol ; 38(5): 573-586, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37017830

RESUMO

Treatment concepts in oncology are becoming increasingly personalized and diverse. Successively, changes in standards of care mandate continuous monitoring of patient pathways and clinical outcomes based on large, representative real-world data. The German Cancer Consortium's (DKTK) Clinical Communication Platform (CCP) provides such opportunity. Connecting fourteen university hospital-based cancer centers, the CCP relies on a federated IT-infrastructure sourcing data from facility-based cancer registry units and biobanks. Federated analyses resulted in a cohort of 600,915 patients, out of which 232,991 were incident since 2013 and for which a comprehensive documentation is available. Next to demographic data (i.e., age at diagnosis: 2.0% 0-20 years, 8.3% 21-40 years, 30.9% 41-60 years, 50.1% 61-80 years, 8.8% 81+ years; and gender: 45.2% female, 54.7% male, 0.1% other) and diagnoses (five most frequent tumor origins: 22,523 prostate, 18,409 breast, 15,575 lung, 13,964 skin/malignant melanoma, 9005 brain), the cohort dataset contains information about therapeutic interventions and response assessments and is connected to 287,883 liquid and tissue biosamples. Focusing on diagnoses and therapy-sequences, showcase analyses of diagnosis-specific sub-cohorts (pancreas, larynx, kidney, thyroid gland) demonstrate the analytical opportunities offered by the cohort's data. Due to its data granularity and size, the cohort is a potential catalyst for translational cancer research. It provides rapid access to comprehensive patient groups and may improve the understanding of the clinical course of various (even rare) malignancies. Therefore, the cohort may serve as a decisions-making tool for clinical trial design and contributes to the evaluation of scientific findings under real-world conditions.


Assuntos
Neoplasias , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Adulto Jovem , Neoplasias/diagnóstico , Neoplasias/epidemiologia , Neoplasias/terapia , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes
3.
J Med Virol ; 94(7): 3101-3111, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35229317

RESUMO

Although vaccines are currently used to control the coronavirus disease 2019 (COVID-19) pandemic, treatment options are urgently needed for those who cannot be vaccinated and for future outbreaks involving new severe acute respiratory syndrome coronavirus virus 2 (SARS-CoV-2) strains or coronaviruses not covered by current vaccines. Thus far, few existing antivirals are known to be effective against SARS-CoV-2 and clinically successful against COVID-19. As part of an immediate response to the COVID-19 pandemic, a high-throughput, high content imaging-based SARS-CoV-2 infection assay was developed in VeroE6 African green monkey kidney epithelial cells expressing a stable enhanced green fluorescent protein (VeroE6-eGFP cells) and was used to screen a library of 5676 compounds that passed Phase 1 clinical trials. Eight drugs (nelfinavir, RG-12915, itraconazole, chloroquine, hydroxychloroquine, sematilide, remdesivir, and doxorubicin) were identified as inhibitors of in vitro anti-SARS-CoV-2 activity in VeroE6-eGFP and/or Caco-2 cell lines. However, apart from remdesivir, toxicity and pharmacokinetic data did not support further clinical development of these compounds for COVID-19 treatment.


Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Animais , Humanos , Antivirais/farmacologia , Células CACO-2 , Chlorocebus aethiops , Ensaios de Triagem em Larga Escala , Pandemias
4.
J Med Virol ; 93(6): 3985-3990, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33300183

RESUMO

In AMBER and EMERALD, darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) 800/150/200/10 mg demonstrated high virological response and low virological failure (VF) through week 96. Week 96 resistance analyses are presented. Post-baseline samples for genotyping/phenotyping were analyzed from protocol-defined-VFs with viral load (VL) ≥ 400 copies/ml at failure/later time points. Post-hoc analyses were deep sequencing (AMBER) and HIV-1 proviral DNA sequencing from baseline samples (VL < 50 copies/ml) (EMERALD). Through week 96 across studies, no darunavir, primary protease inhibitor (PI), or tenofovir resistance-associated-mutations (RAMs) occurred in patients continuing (N = 1125) or switching to D/C/F/TAF (N = 715). M184I/V (emtricitabine RAM) was detected in one patient in each arm of AMBER. In EMERALD D/C/F/TAF patients with prior VF and baseline genoarchive data (N = 98), 4% had darunavir RAMs, 36% emtricitabine RAMs, mainly at position 184 (32%), 4% tenofovir RAMs, and 19% ≥3 thymidine-analogue-associated-mutations at screening. The predicted phenotype showed 0% had reduced susceptibility to darunavir, 37% to emtricitabine, and 22% to tenofovir. All achieved VL < 50 copies/ml at week 96/prior discontinuation, with no VF. D/C/F/TAF has a high barrier to resistance; no darunavir, primary PI, or tenofovir RAMs occurred through 96 weeks in AMBER and EMERALD. In EMERALD, baseline archived darunavir, emtricitabine, and tenofovir RAMs in patients with prior VF did not preclude virologic response.


Assuntos
Alanina/uso terapêutico , Fármacos Anti-HIV/uso terapêutico , Cobicistat/uso terapêutico , Darunavir/uso terapêutico , Farmacorresistência Viral Múltipla/genética , Emtricitabina/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Tenofovir/análogos & derivados , Alanina/administração & dosagem , Fármacos Anti-HIV/administração & dosagem , Cobicistat/administração & dosagem , Darunavir/administração & dosagem , Combinação de Medicamentos , Emtricitabina/administração & dosagem , HIV-1/genética , Análise de Sequência de DNA , Comprimidos , Tenofovir/administração & dosagem , Tenofovir/uso terapêutico , Carga Viral/efeitos dos fármacos
5.
J Med Virol ; 93(7): 4454-4460, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33666253

RESUMO

Although vaccination campaigns are currently being rolled out to prevent coronavirus disease (COVID-19), antivirals will remain an important adjunct to vaccination. Antivirals against coronaviruses do not exist, hence global drug repurposing efforts have been carried out to identify agents that may provide clinical benefit to patients with COVID-19. Itraconazole, an antifungal agent, has been reported to have activity against animal coronaviruses. Using cell-based phenotypic assays, the in vitro antiviral activity of itraconazole and 17-OH itraconazole was assessed against clinical isolates from a German and Belgian patient infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Itraconazole demonstrated antiviral activity in human Caco-2 cells (EC50 = 2.3 µM; 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay). Similarly, its primary metabolite, 17-OH itraconazole, showed inhibition of SARS-CoV-2 activity (EC50 = 3.6 µM). Remdesivir inhibited viral replication with an EC50 = 0.4 µM. Itraconazole and 17-OH itraconazole resulted in a viral yield reduction in vitro of approximately 2-log10 and approximately 1-log10 , as measured in both Caco-2 cells and VeroE6-eGFP cells, respectively. The viral yield reduction brought about by remdesivir or GS-441524 (parent nucleoside of the antiviral prodrug remdesivir; positive control) was more pronounced, with an approximately 3-log10 drop and >4-log10 drop in Caco-2 cells and VeroE6-eGFP cells, respectively. Itraconazole and 17-OH itraconazole exert in vitro low micromolar activity against SARS-CoV-2. Despite the in vitro antiviral activity, itraconazole did not result in a beneficial effect in hospitalized COVID-19 patients in a clinical study (EudraCT Number: 2020-001243-15).


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , Furanos/farmacologia , Itraconazol/farmacologia , Pirróis/farmacologia , SARS-CoV-2/efeitos dos fármacos , Triazinas/farmacologia , Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Alanina/farmacologia , Animais , Células CACO-2 , Linhagem Celular Tumoral , Chlorocebus aethiops , Reposicionamento de Medicamentos , Humanos , Células Vero , Replicação Viral/efeitos dos fármacos
6.
Arch Anim Nutr ; 75(4): 237-250, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34251937

RESUMO

Insect meal (IM) produced from edible insects, such as Tenebrio molitor, has been recognised as a potentially suitable protein component in feeding rations for monogastric livestock. While several studies with broilers have shown that animal´s health is not negatively affected by IM, less is known with regard to the influence of IM on metabolism of pigs. The present study investigates whether IM from Tenebrio molitor larvae causes oxidative stress and activates oxidative stress-sensitive signalling pathways in key metabolic tissues of pigs. To address this question, male 5-week-old crossbred pigs were randomly assigned to three groups of 10 pigs each and fed nutrient-adequate, isonitrogenous diets either without (CON) or with 5% IM or 10% IM from Tenebrio molitor larvae for 4 weeks. Concentrations of thiobarbituric acid reactive substances, tocopherols and glutathione in liver, gastrocnemius muscle and/or plasma did not differ between groups. Activities of the antioxidant enzymes catalase (CAT), glutathione peroxidase (GPX) and superoxide dismutase (SOD) in the liver and of GPX and SOD in gastrocnemius muscle were not different between groups, whereas the activity of CAT in skeletal muscle was increased in the two IM-fed groups compared to group CON (p < 0.05). The mRNA levels of most of the target genes of oxidative stress-sensitive signalling pathways, such as nuclear factor-κB, nuclear factor erythroid 2-related factor 2 and endoplasmic reticulum stress-induced unfolded protein response, in liver and gastrocnemius muscle did not differ between the three groups. The present study shows that feeding a diet containing adequate levels of antioxidants, such as vitamin E and selenium, and Tenebrio molitor larvae meal as a protein component neither causes oxidative stress nor activates oxidative stress-sensitive signalling pathways in key metabolic tissues of growing pigs. Based on these observations, IM from Tenebrio molitor larvae can be regarded as a safe source of protein in growing pigs.


Assuntos
Tenebrio , Ração Animal/análise , Animais , Antioxidantes , Galinhas , Dieta/veterinária , Larva , Masculino , Suínos
7.
J Viral Hepat ; 27(11): 1127-1137, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32579776

RESUMO

Four weeks of once-daily oral JNJ-56136379 (JNJ-6379; 25, 75, 150 or 250 mg), a class-N capsid assembly modulator (CAM-N), was well tolerated with potent antiviral activity in treatment-naïve, chronic hepatitis B e antigen-positive and hepatitis B e antigen-negative patients (NCT02662712). Hepatitis B virus (HBV) genome sequence analysis, using HBV DNA next-generation sequence technology, was performed, and impact of substitutions on efficacy was assessed. Analyses focused on HBV core protein amino acid positions associated with JNJ-6379 and/or other CAMs in vitro resistance, and those within the CAM-binding pocket. 31/57 patients had ≥ 1 polymorphism at any of the core amino acid positions of interest, most frequently at positions 38 (32%), 105 (23%) and 109 (14%). None of these polymorphisms are known to reduce JNJ-6379 in vitro activity (fold change [FC] in 50% effective concentration <3.0). Two JNJ-6379-treated patients carried a Y118F baseline core polymorphism known to reduce JNJ-6379 activity in vitro (FC = 6.6) and had HBV DNA declines of 2.77 (75 mg) and 2.19 log10 IU/mL (150 mg) at the end of treatment. One 75 mg JNJ-6379-treated patient had an emerging T109S substitution (FC = 1.8; HBV DNA decline 3.18 log10 IU/mL). A 25 mg JNJ-6379-treated patient had on-treatment enrichment of Y118F variant (HBV DNA decline 2.13 log10 IU/mL). In conclusion, baseline polymorphisms and enrichment of substitutions reducing JNJ-6379 in vitro activity were rare, with no consistent impact on virological response during a 4-week phase 1b study. Emergence of resistance to longer treatments of JNJ-6379 will be evaluated in phase 2 studies.


Assuntos
Vírus da Hepatite B , Hepatite B Crônica , Antivirais/uso terapêutico , Capsídeo , DNA Viral , Antígenos E da Hepatite B , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Humanos , Resultado do Tratamento
8.
J Nutr ; 149(4): 566-577, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30726942

RESUMO

BACKGROUND: Specific dietary proteins exert strong health-related effects compared with casein. OBJECTIVE: Herein, the hypothesis was tested using screening and conventional biochemical and molecular biological techniques that protein-rich insect meal compared with casein influences metabolic health in hyperlipidemic rats. METHODS: A 4-wk feeding trial with male, 8-wk-old homozygous obese Zucker rats (n = 36) and male, 8-wk-old heterozygous lean Zucker rats (n = 12) was performed. Obese rats were randomly divided into 3 obese groups (OC, OI50, and OI100) of 12 rats each and lean rats served as a lean control group (LC). LC and OC were fed a control diet with 20% casein as protein source, whereas in OI50 and OI100 50% and 100% of the casein, respectively, was replaced isonitrogenously by insect meal from Tenebrio molitor L. All data were analyzed by 1-factor ANOVA, except transcriptomic data which were analyzed by groupwise comparisons with the OC group. RESULTS: Transcript profiling revealed a coordinated inhibition by -17% to -521% and -37% to -859% of genes involved in fatty acid, triacylglycerol (TG), and cholesterol biosynthesis in the livers of OI100 and OI50, respectively, compared with OC (P < 0.05). Enzyme activities of fatty acid synthase, glucose-6 phosphate dehydrogenase, and 3-hydroxy-3-methylglutaryl-coenzyme-A reductase in the liver were 100-150% greater in OC compared with LC, but reduced by 50-60% in OI100 compared with OC (P < 0.05), to the same level as in LC. Liver and plasma concentrations of TG and cholesterol were 250-1000%, 30-800%, and 40-600% higher in OC, OI50, and OI100, respectively, than in LC (P < 0.05), but 40-60% and 20-60% lower in OI100 and OI50, respectively, than in group OC (P < 0.05). Plasma and liver concentrations of homocysteine were 20-30% lower in group OI100 than in group OC (P < 0.05). CONCLUSION: Insect meal exerts pronounced lipid-lowering effects in hyperlipidemic rats and, thus, might be useful for hyperlipidemic individuals.


Assuntos
Ração Animal/análise , Proteínas Alimentares , Insetos , Lipídeos/sangue , Animais , Biologia Computacional , Regulação da Expressão Gênica/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Análise Serial de Proteínas , Distribuição Aleatória , Ratos , Ratos Zucker , Aumento de Peso
9.
Virol J ; 14(1): 101, 2017 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-28569206

RESUMO

BACKGROUND: In study TMC647055HPC2001, a 3-direct-acting-antiviral (DAA) regimen combining NS3/4A protease inhibitor simeprevir (SMV), non-nucleoside NS5B inhibitor TMC647055/ritonavir (RTV) and NS5A inhibitor JNJ-56914845 resulted in high sustained virologic response 12 weeks after actual end of treatment (SVR12) in chronic hepatitis C virus (HCV) genotype 1-infected patients. SVR12 rates were generally lower in the 2-DAA regimen SMV + TMC647055/RTV with or without ribavirin. The objective of this study was to identify and characterise pre-existing and emerging resistance-associated variants (RAVs) in patients enrolled in study TMC647055HPC2001. METHODS: HCV population sequencing analyses were performed on baseline isolates from all patients (n = 90) and post-baseline isolates from patients with virologic failure (n = 22). In addition, deep sequencing and phenotypic analyses were performed on selected baseline and post-baseline isolates. RESULTS: The majority of patients with virologic failure had emerging RAVs to all study drugs at the time of failure: in all 22 patients SMV RAVs emerged at NS3 positions 80, 155, 156 and/or 168, consistent with the known SMV resistance profile. Emerging TMC647055 RAVs at NS5B position 495 were detected in the majority of patients (16/22), and all 5 patients who failed the 3-DAA regimen had emerging JNJ-56914845 RAVs at NS5A positions 30 and/or 31. While at the end of study emerging SMV and TMC647055 RAVs were no longer observed by population sequencing in 40% (8/20) and 62.5% (10/16) of patients with follow-up data available, respectively, emerging JNJ-56914845 RAVs were still detected in all (5/5) patients. CONCLUSIONS: Virologic failure in the 2- and 3-DAA combinations was, in the majority of patients, associated with the emergence of RAVs to all study drugs. While emerging SMV and TMC647055 RAVs became undetectable during follow-up, JNJ-56914845 RAVs in NS5A were still observed at end of study. TRIAL REGISTRATION NUMBER: NCT01724086 (date of registration: September 26, 2012).


Assuntos
Antivirais/uso terapêutico , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Ritonavir/uso terapêutico , Simeprevir/uso terapêutico , Sulfonamidas/uso terapêutico , Carbamatos/uso terapêutico , Farmacorresistência Viral , Técnicas de Genotipagem , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C Crônica/virologia , Humanos , Ribavirina/uso terapêutico , Análise de Sequência de DNA , Falha de Tratamento , Valina/análogos & derivados , Valina/uso terapêutico
10.
J Med Virol ; 88(5): 798-806, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26412111

RESUMO

Minority variants (1.0-25.0%) were evaluated by deep sequencing (DS) at baseline and virological failure (VF) in a selection of antiretroviral treatment-naïve, HIV-1-infected patients from the rilpivirine ECHO/THRIVE phase III studies. Linkage between frequently emerging resistance-associated mutations (RAMs) was determined. DS (llIumina®) and population sequencing (PS) results were available at baseline for 47 VFs and time of failure for 48 VFs; and at baseline for 49 responders matched for baseline characteristics. Minority mutations were accurately detected at frequencies down to 1.2% of the HIV-1 quasispecies. No baseline minority rilpivirine RAMs were detected in VFs; one responder carried 1.9% F227C. Baseline minority mutations associated with resistance to other non-nucleoside reverse transcriptase inhibitors (NNRTIs) were detected in 8/47 VFs (17.0%) and 7/49 responders (14.3%). Baseline minority nucleoside/nucleotide reverse transcriptase inhibitor (NRTI) RAMs M184V and L210W were each detected in one VF (none in responders). At failure, two patients without NNRTI RAMs by PS carried minority rilpivirine RAMs K101E and/or E138K; and five additional patients carried other minority NNRTI RAMs V90I, V106I, V179I, V189I, and Y188H. Overall at failure, minority NNRTI RAMs and NRTI RAMs were found in 29/48 (60.4%) and 16/48 VFs (33.3%), respectively. Linkage analysis showed that E138K and K101E were usually not observed on the same viral genome. In conclusion, baseline minority rilpivirine RAMs and other NNRTI/NRTI RAMs were uncommon in the rilpivirine arm of the ECHO and THRIVE studies. DS at failure showed emerging NNRTI resistant minority variants in seven rilpivirine VFs who had no detectable NNRTI RAMs by PS.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Transcriptase Reversa do HIV/genética , Sequenciamento de Nucleotídeos em Larga Escala , Rilpivirina/uso terapêutico , Adulto , Substituição de Aminoácidos , Ensaios Clínicos Fase III como Assunto , Feminino , Humanos , Masculino , Mutação de Sentido Incorreto , Seleção Genética , Fatores de Tempo , Falha de Tratamento
11.
J Hepatol ; 62(5): 1008-14, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25445400

RESUMO

BACKGROUND & AIMS: Simeprevir is an oral hepatitis C virus (HCV) NS3/4A protease inhibitor approved for treatment of chronic HCV infection. Baseline NS3 polymorphisms in all patients and emerging mutations in patients who failed to achieve sustained virologic response (SVR) with simeprevir plus peginterferon/ribavirin (PR) in Phase IIb/III studies are described. METHODS: Baseline sequencing data were available for 2007 genotype 1 (GT1)-infected patients. Post-baseline data were available for 197/245 simeprevir-treated patients who did not achieve SVR. In vitro simeprevir susceptibility was assessed in a transient replicon assay as site-directed mutants or in chimeric replicons with patient-derived NS3 protease sequences. RESULTS: Baseline NS3 polymorphisms at positions associated with reduced in vitro susceptibility to simeprevir (43, 80, 122, 155, 156, and/or 168; EC50 fold change >2.0) were uncommon (1.3% [26/2007]), with the exception of Q80K, which confers ∼10-fold reduction in simeprevir activity in vitro (13.7% [274/2007]; GT1a 29.5% [269/911], GT1b 0.5% [5/1096]). Baseline Q80K had minor effect on initial response to simeprevir/PR, but resulted in lower SVR rates. Overall, 91.4% of simeprevir-treated patients [180/197] without SVR had emerging mutations at NS3 positions 80, 122, 155, and/or 168 at failure (mainly R155K in GT1a with and without Q80K, and D168V in GT1b), conferring high-level resistance in vitro (EC50 fold change >50). Emerging mutations were no longer detectable by population sequencing at study end in 50% [90/180] of patients (median follow-up 28.4weeks). CONCLUSIONS: Simeprevir treatment failure was usually associated with emerging high-level resistance mutations, which became undetectable over time in half of the patients.


Assuntos
Hepacivirus , Hepatite C Crônica , Interferon-alfa/farmacologia , Polietilenoglicóis/farmacologia , Ribavirina/farmacologia , Simeprevir/farmacologia , Proteínas não Estruturais Virais , Antivirais/farmacologia , Método Duplo-Cego , Farmacorresistência Viral/genética , Quimioterapia Combinada/métodos , Feminino , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Proteínas Recombinantes/farmacologia , Fatores de Tempo , Falha de Tratamento , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/genética
12.
Antimicrob Agents Chemother ; 59(12): 7548-57, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26392483

RESUMO

Simeprevir (TMC435) is a once-daily, single-pill, oral hepatitis C virus (HCV) NS3 protease inhibitor approved for the treatment of chronic HCV infection. Phenotypic characterization of baseline isolates and isolates from HCV genotype 1-infected patients failing with a simeprevir-based regimen was performed using chimeric replicons carrying patient-derived NS3 protease sequences. Cutoff values differentiating between full susceptibility to simeprevir (≤ 2.0-fold reduction in simeprevir activity) and low-level versus high-level resistance (≥ 50-fold reduction in simeprevir activity) were determined. The median simeprevir fold change in the 50% effective concentration (FC) of pretreatment genotype 1a isolates, with and without Q80K, and genotype 1b isolates was 11, 0.9, and 0.4, respectively. Naturally occurring NS3 polymorphisms that reduced simeprevir activity, other than Q80K, were uncommon in the simeprevir studies and generally conferred low-level resistance in vitro. Although the proportion of patients with failure differed by HCV geno/subtype and/or presence of baseline Q80K, the level of simeprevir resistance observed at failure was similarly high irrespective of type of failure, HCV genotype 1 subtype, and presence or absence of baseline Q80K. At the end of the study, simeprevir activity against isolates that lost the emerging amino acid substitution returned to pretreatment values. Activity of simeprevir against clinical isolates and site-directed mutant replicons harboring the corresponding single or double amino acid substitutions correlated well, showing that simeprevir resistance can be attributed to these substitutions. In conclusion, pretreatment NS3 isolates were generally fully susceptible (FC, ≤ 2.0) or conferred low-level resistance to simeprevir in vitro (FC, >2.0 and <50). Treatment failure with a simeprevir-based regimen was associated with emergence of high-level-resistance variants (FC, ≥ 50).


Assuntos
Antivirais/farmacologia , Farmacorresistência Viral/efeitos dos fármacos , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Simeprevir/farmacologia , Proteínas não Estruturais Virais/genética , Substituição de Aminoácidos , Farmacorresistência Viral/genética , Expressão Gênica , Genótipo , Hepacivirus/enzimologia , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Testes de Sensibilidade Microbiana , Mutagênese Sítio-Dirigida , Proteínas Mutantes Quiméricas/genética , Proteínas Mutantes Quiméricas/metabolismo , Polimorfismo Genético , Inibidores de Proteases/farmacologia , Replicon , Falha de Tratamento , Proteínas não Estruturais Virais/metabolismo
13.
Antimicrob Agents Chemother ; 59(5): 2746-55, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25712364

RESUMO

In treating hepatitis B virus (HBV) and human immunodeficiency virus (HIV) infections, the rapid reselection of resistance-associated variants (RAVs) is well known in patients with repeated exposure to the same class of antiviral agents. For chronic hepatitis C patients who have experienced virologic failure with direct-acting antiviral drugs, the potential for the reselection of persistent RAVs is unknown. Nine patients who received 14 days of telaprevir monotherapy were retreated with telaprevir-based triple therapy 4.3 to 5.7 years later. In four patients with virologic failure with both telaprevir-containing regimens, population-based and deep sequencing (454 GS-FLX) of the NS3 protease gene were performed before and at treatment failure (median coverage, 4,651 reads). Using deep sequencing, with a threshold of 1.0% for variant calling, no isolates were found harboring RAVs at the baseline time points. While population-based sequencing uncovered similar resistance patterns (V36M plus R155K for subtype 1a and V36A for subtype 1b) in all four patients after the first and second telaprevir treatments, deep sequencing analysis revealed a median of 7 (range, 4 to 23) nucleotide substitutions on the NS3 backbone of the resistant strains, together with large phylogenetic differences between viral quasispecies, making the survival of resistant isolates highly unlikely. In contrast, in a comparison of the two baseline time points, the median number of nucleotide exchanges in the wild-type isolates was only 3 (range, 2 to 8), reflecting the natural evolution of the NS3 gene. In patients with repeated direct antiviral treatment, a continuous evolution of HCV quasispecies was observed, with no clear evidence of persistence and reselection but strong signs of independent de novo generation of resistance. Antiviral therapy for chronic viral infections, like HIV, hepatitis B virus (HBV), or hepatitis C virus (HCV), faces several challenges. These viruses have evolved survival strategies and proliferate by escaping the host's immune system. The development of direct-acting antiviral agents is an important achievement in fighting these infections. Viral variants conferring resistance to direct antiviral drugs lead to treatment failure. For HIV/HBV, it is well known that viral variants associated with treatment failure will be archived and reselected rapidly during retreatment with the same drug/class of drugs. We explored the mechanisms and rules of how resistant variants are selected and potentially reselected during repeated direct antiviral therapies in chronically HCV-infected patients. Interestingly, in contrast to HIV and HBV, we could not prove long-term persistence and reselection of resistant variants in HCV patients who failed protease inhibitor-based therapy. This may have important implications for the potential to reuse direct-acting antivirals in patients who failed the initial direct antiviral treatment. (The phase IIIb study described in this paper is registered at ClinicalTrials.gov under registration number NCT01054573.).


Assuntos
Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepacivirus/patogenicidade , Oligopeptídeos/uso terapêutico , Proteínas não Estruturais Virais/antagonistas & inibidores , Método Duplo-Cego , Hepatite C , Humanos
14.
Gastroenterology ; 146(3): 744-753.e3, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24316262

RESUMO

BACKGROUND & AIMS: We performed an open-label, multicenter, phase 3 study of the safety and efficacy of twice-daily telaprevir in treatment-naive patients with chronic hepatitis C virus (HCV) genotype 1 infection, including those with cirrhosis. METHODS: Patients were randomly assigned to groups treated with telaprevir 1125 mg twice daily or 750 mg every 8 hours plus peginterferon alfa-2a and ribavirin for 12 weeks; patients were then treated with peginterferon alfa-2a and ribavirin alone for 12 weeks if their level of HCV RNA at week 4 was <25 IU/mL or for 36 weeks if their level was higher. The primary objective was to demonstrate noninferiority of telaprevir twice daily versus every 8 hours in producing a sustained virological response 12 weeks after the end of therapy (SVR12) (based on a -11% lower limit of the 95% lower confidence interval for the difference between groups). RESULTS: At baseline, of 740 patients, 85% had levels of HCV RNA ≥800,000 IU/mL, 28% had fibrosis (F3-F4), 14% had cirrhosis (F4), 57% were infected with HCV genotype 1a, and 71% had the non-CC IL28B genotype. Of patients who were treated with telaprevir twice daily, 74.3% achieved SVR12 compared with 72.8% of patients who were treated with telaprevir every 8 hours (difference in response, 1.5%; 95% confidence interval, -4.9% to 12.0%), so telaprevir twice daily is noninferior to telaprevir every 8 hours. All subgroups of patients who were treated with telaprevir twice daily versus those who were treated every 8 hours had similar rates of SVR12. The most frequent adverse events (AEs) in the telaprevir phase were fatigue (47%), pruritus (43%), anemia (42%), nausea (37%), rash (35%), and headache (26%); serious AEs were reported in 9% of patients. Rates of AEs and serious AEs were similar or slightly higher among patients treated with telaprevir every 8 hours. CONCLUSIONS: Based on a phase 3 trial, telaprevir twice daily is noninferior to every 8 hours in producing SVR12, with similar levels of safety and tolerability. These results support use of telaprevir twice daily in patients with chronic HCV genotype 1 infection, including those with cirrhosis. ClinicalTrials.gov, Number: NCT01241760.


Assuntos
Antivirais/administração & dosagem , Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Oligopeptídeos/administração & dosagem , Oligopeptídeos/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Antivirais/efeitos adversos , Relação Dose-Resposta a Droga , Esquema de Medicação , Quimioterapia Combinada , Fadiga/epidemiologia , Feminino , Genótipo , Cefaleia/epidemiologia , Hepacivirus/genética , Hepatite C Crônica/sangue , Humanos , Incidência , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Náusea/epidemiologia , Oligopeptídeos/efeitos adversos , Polietilenoglicóis/efeitos adversos , RNA Viral/sangue , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Ribavirina/efeitos adversos , Resultado do Tratamento
15.
J Clin Microbiol ; 53(4): 1264-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25653396

RESUMO

Protease inhibitor (PI)-based response-guided triple therapies for hepatitis C virus (HCV) infection are still widely used. Noncirrhotic treatment-naive and prior relapser patients receiving telaprevir-based treatment are eligible for shorter, 24-week total therapy if HCV RNA is undetectable at both weeks 4 and 12. In this study, the concordance in HCV RNA assessments between the Roche High Pure System/Cobas TaqMan and Abbott RealTime HCV RNA assays and the impacts of different HCV RNA cutoffs on treatment outcome were evaluated. A total of 2,629 samples from 663 HCV genotype 1 patients receiving telaprevir/pegylated interferon/ribavirin in OPTIMIZE were analyzed using the High Pure System and reanalyzed using Abbott RealTime (limits of detection, 15.1 IU/ml versus 8.3 IU/ml; limits of quantification, 25 IU/ml versus 12 IU/ml, respectively). Overall, good concordance was observed between the assays. Using undetectable HCV RNA at week 4, 34% of the patients would be eligible for shorter treatment duration with Abbott RealTime versus 72% with the High Pure System. However, using <12 IU/ml for Abbott RealTime, a similar proportion (74%) would be eligible. Of the patients receiving 24-week total therapy, 87% achieved a sustained virologic response with undetectable HCV RNA by the High Pure System or <12 IU/ml by Abbott RealTime; however, 92% of the patients with undetectable HCV RNA by Abbott RealTime achieved a sustained virologic response. Using undetectable HCV RNA as the cutoff, the more sensitive Abbott RealTime assay would identify fewer patients eligible for shorter treatment than the High Pure System. Our data confirm the <12-IU/ml cutoff, as previously established in other studies of the Abbott RealTime assay, to determine eligibility for shortened PI-based HCV treatment. (The study was registered with ClinicalTrials.gov under registration no. NCT01241760.).


Assuntos
Antivirais/uso terapêutico , Monitoramento de Medicamentos/métodos , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/uso terapêutico , RNA Viral/sangue , Carga Viral/métodos , Quimioterapia Combinada/métodos , Hepacivirus/genética , Hepatite C Crônica/virologia , Humanos , Interferon-alfa/uso terapêutico , Técnicas de Diagnóstico Molecular/métodos , Estudos Retrospectivos , Ribavirina/uso terapêutico , Resultado do Tratamento
16.
Liver Int ; 35(2): 448-54, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25319731

RESUMO

BACKGROUND & AIMS: Predictors of response to treatment with peginterferon plus ribavirin are well established. In these post-hoc analyses of the REALIZE study, we sought to identify predictors of response for telaprevir-based triple therapy. METHODS: Patients from the REALIZE study with baseline data for all predictors evaluated (including baseline disease characteristics and demographics, prior treatment response and baseline laboratory assessments) were included in the post-hoc analyses (n = 465). Univariate and multivariate analyses were used to evaluate factors predicting treatment outcomes. RESULTS: Sustained viral response (SVR) rates were 86% in prior relapsers, 63% in prior partial responders and 32% in prior null-responders. In the final multivariate analysis, baseline factors predicting SVR were prior response to treatment [Odds ratio (OR) = 2.80; 95% confidence interval (CI), 2.13-3.69], low-density lipoprotein (LDL) (≥2.6 mmol/L) (OR = 2.11; 95% CI, 1.52-2.93), HCV genotype (OR = 0.58; 95% CI, 0.36-0.93), and maximum alanine amino transferase and aspartate amino transferase (OR = 0.62; 95% CI, 0.40-0.97). CONCLUSIONS: Prior response to peginterferon plus ribavirin treatment and LDL levels are the main independent predictive markers of response with telaprevir-based triple therapy.


Assuntos
Biomarcadores/sangue , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Lipoproteínas LDL/sangue , Oligopeptídeos/uso terapêutico , Quimioterapia Combinada , Hepatite C/genética , Humanos , Interferon-alfa/uso terapêutico , Razão de Chances , Polietilenoglicóis/uso terapêutico , RNA Viral/sangue , Proteínas Recombinantes/uso terapêutico , Análise de Regressão , Ribavirina/uso terapêutico , Resultado do Tratamento
17.
PLoS Comput Biol ; 10(8): e1003772, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25101970

RESUMO

For patients infected with hepatitis C virus (HCV), the combination of the direct-acting antiviral agent telaprevir, pegylated-interferon alfa (Peg-IFN), and ribavirin (RBV) significantly increases the chances of sustained virologic response (SVR) over treatment with Peg-IFN and RBV alone. If patients do not achieve SVR with telaprevir-based treatment, their viral population is often significantly enriched with telaprevir-resistant variants at the end of treatment. We sought to quantify the evolutionary dynamics of these post-treatment resistant variant populations. Previous estimates of these dynamics were limited by analyzing only population sequence data (20% sensitivity, qualitative resistance information) from 388 patients enrolled in Phase 3 clinical studies. Here we add clonal sequence analysis (5% sensitivity, quantitative) for a subset of these patients. We developed a computational model which integrates both the qualitative and quantitative sequence data, and which forms a framework for future analyses of drug resistance. The model was qualified by showing that deep-sequence data (1% sensitivity) from a subset of these patients are consistent with model predictions. When determining the median time for viral populations to revert to 20% resistance in these patients, the model predicts 8.3 (95% CI: 7.6, 8.4) months versus 10.7 (9.9, 12.8) months estimated using solely population sequence data for genotype 1a, and 1.0 (0.0, 1.4) months versus 0.9 (0.0, 2.7) months for genotype 1b. For each individual patient, the time to revert to 20% resistance predicted by the model was typically comparable to or faster than that estimated using solely population sequence data. Furthermore, the model predicts a median of 11.0 and 2.1 months after treatment failure for viral populations to revert to 99% wild-type in patients with HCV genotypes 1a or 1b, respectively. Our modeling approach provides a framework for projecting accurate, quantitative assessment of HCV resistance dynamics from a data set consisting of largely qualitative information.


Assuntos
Antivirais , Hepacivirus , Hepatite C , Modelos Biológicos , Oligopeptídeos , Carga Viral/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/uso terapêutico , Biologia Computacional , Farmacorresistência Viral , Quimioterapia Combinada , Hepacivirus/classificação , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Humanos , Oligopeptídeos/farmacologia , Oligopeptídeos/uso terapêutico
18.
Plant Cell Rep ; 34(5): 745-54, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25558819

RESUMO

KEY MESSAGE: Improving Agrobacterium -mediated transformation frequency and event quality by increasing binary plasmid copy number and appropriate strain selection is reported in an elite maize cultivar. Agrobacterium-mediated maize transformation is a well-established method for gene testing and for introducing useful traits in a commercial biotech product pipeline. To develop a highly efficient maize transformation system, we investigated the effect of two Agrobacterium tumefaciens strains and three different binary plasmid origins of replication (ORI) on transformation frequency, vector backbone insertion, single copy event frequency (percentage of events which are single copy for all transgenes), quality event frequency (percentage of single copy events with no vector backbone insertions among all events generated; QE) and usable event quality frequency (transformation frequency times QE frequency; UE) in an elite maize cultivar PHR03. Agrobacterium strain AGL0 gave a higher transformation frequency, but a reduced QE frequency than LBA4404 due to a higher number of vector backbone insertions. Higher binary plasmid copy number positively correlated with transformation frequency and usable event recovery. The above findings can be exploited to develop high-throughput transformation protocols, improve the quality of transgenic events in maize and other plants.


Assuntos
Agrobacterium tumefaciens/genética , Plasmídeos/genética , Transformação Genética , Zea mays/genética , Agrobacterium tumefaciens/fisiologia , Variações do Número de Cópias de DNA , DNA Bacteriano/genética , Vetores Genéticos , Plantas Geneticamente Modificadas , Origem de Replicação , Especificidade da Espécie , Transgenes
19.
J Infect Dis ; 210(12): 1871-80, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24943725

RESUMO

BACKGROUND: Population sequencing (PS) has shown that telaprevir-resistant variants are not typically detectable at baseline (prevalence, ≤5% of patients), and most variants present at the time of treatment failure are no longer detectable at the end of the study. METHODS: To gain insight into the evolution of telaprevir-resistant variants, their baseline prevalence and persistence after treatment was investigated using a more sensitive, deep-sequencing (DS) technique in a large number of treatment-experienced patients from the REALIZE study who were infected with hepatitis C virus genotype 1. RESULTS: Before treatment initiation, telaprevir-resistant variants (T54A, T54S, or R155K in 1%-2% of the viral population) were detected by DS in a fraction (2%) of patients for whom PS failed to detect resistance; these variants were not necessarily detected at the time of treatment failure. Of 49 patients in whom telaprevir-resistant variants were detected by PS at the time of treatment failure but not at the end of the study, DS revealed the presence of variants (V36A/L/M, T54S, or R155K in 1%-36% of the viral population) in 16 patients (33%) at the end of the study. CONCLUSIONS: Similar to PS findings, DS analysis revealed that the frequency of telaprevir-resistant variants before treatment was also low, and variants detected at the time of treatment failure were no longer detectable in the majority of patients during follow-up.


Assuntos
Antivirais/uso terapêutico , Proteínas de Transporte/genética , Hepacivirus/enzimologia , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/uso terapêutico , Proteínas não Estruturais Virais/genética , Farmacorresistência Viral , Hepacivirus/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Taxa de Mutação , Prevalência
20.
N Engl J Med ; 364(25): 2417-28, 2011 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-21696308

RESUMO

BACKGROUND: Up to 60% of patients with hepatitis C virus (HCV) genotype 1 infection do not have a sustained virologic response to therapy with peginterferon alfa plus ribavirin. METHODS: In this randomized, phase 3 trial, we evaluated the addition of telaprevir to peginterferon alfa-2a plus ribavirin in patients with HCV genotype 1 infection who had no response or a partial response to previous therapy or who had a relapse after an initial response. A total of 663 patients were assigned to one of three groups: the T12PR48 group, which received telaprevir for 12 weeks and peginterferon plus ribavirin for a total of 48 weeks; the lead-in T12PR48 group, which received 4 weeks of peginterferon plus ribavirin followed by 12 weeks of telaprevir and peginterferon plus ribavirin for a total of 48 weeks; and the control group (PR48), which received peginterferon plus ribavirin for 48 weeks. The primary end point was the rate of sustained virologic response, which was defined as undetectable HCV RNA 24 weeks after the last planned dose of a study drug. RESULTS: Rates of sustained virologic response were significantly higher in the two telaprevir groups than in the control group among patients who had a previous relapse (83% in the T12PR48 group, 88% in the lead-in T12PR48 group, and 24% in the PR48 group), a partial response (59%, 54%, and 15%, respectively), and no response (29%, 33%, and 5%, respectively) (P<0.001 for all comparisons). Grade 3 adverse events (mainly anemia, neutropenia, and leukopenia) were more frequent in the telaprevir groups than in the control group (37% vs. 22%). CONCLUSIONS: Telaprevir combined with peginterferon plus ribavirin significantly improved rates of sustained virologic response in patients with previously treated HCV infection, regardless of whether there was a lead-in phase. (Funded by Tibotec and Vertex Pharmaceuticals; REALIZE ClinicalTrials.gov number, NCT00703118.).


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Oligopeptídeos/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Inibidores de Serina Proteinase/uso terapêutico , Adulto , Idoso , Antivirais/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/efeitos adversos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/efeitos adversos , Polietilenoglicóis/efeitos adversos , RNA Viral/sangue , Proteínas Recombinantes , Recidiva , Retratamento , Ribavirina/efeitos adversos , Análise de Sequência de DNA , Inibidores de Serina Proteinase/efeitos adversos , Carga Viral , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA