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1.
J Virol ; 97(10): e0089223, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37772835

RESUMO

IMPORTANCE: The hepatitis C virus is associated with nearly 300,000 deaths annually. At the core of the virus is an RNA-protein complex called the nucleocapsid, which consists of the viral genome and many copies of the core protein. Because the assembly of the nucleocapsid is a critical step in viral replication, a considerable amount of effort has been devoted to identifying antiviral therapeutics that can bind to the core protein and disrupt assembly. Although several candidates have been identified, little is known about how they interact with the core protein or how those interactions alter the structure and thus the function of this viral protein. Our work biochemically characterizes several of these binding interactions, highlighting both similarities and differences as well as strengths and weaknesses. These insights bolster the notion that this viral protein is a viable target for novel therapeutics and will help to guide future developments of these candidate antivirals.


Assuntos
Antivirais , Hepacivirus , Proteínas do Core Viral , Humanos , Antivirais/metabolismo , Antivirais/farmacologia , Hepacivirus/química , Hepacivirus/efeitos dos fármacos , Hepacivirus/metabolismo , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Nucleocapsídeo/antagonistas & inibidores , Nucleocapsídeo/química , Nucleocapsídeo/metabolismo , Proteínas do Core Viral/antagonistas & inibidores , Proteínas do Core Viral/metabolismo , Montagem de Vírus , Replicação Viral , Imagem Individual de Molécula/métodos , Ligação Proteica
2.
Viruses ; 14(12)2022 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-36560772

RESUMO

Chronic hepatitis C virus (HCV) infections are a worldwide medical problem responsible for diverse types of liver diseases. The NS5B polymerase enzyme has become a very interesting target for the development of anti-HCV drugs owing to its fundamental role in viral replication. Here we report the synthesis of a novel series of 1-substituted phenyl-4(1H)-quinazolinone and 2-methyl-1-substituted phenyl-4(1H)-quinazolinone derivatives and evaluate their activity against HCV in HCV subgenomic replicon assays. The biological data revealed that compound 11a showed the highest activity against HCV GT1b at a micromolar concentration (EC50 = 0.984 µM) followed by compound 11b (EC50 = 1.38 µM). Both compounds 11a and 11b had high selectivity indices (SI = CC50/EC50), 160.71 and 71.75, respectively, which make them very interesting candidates for further development of more potent and selective anti-HCV agents.


Assuntos
Antivirais , Inibidores Enzimáticos , Hepacivirus , Humanos , Antivirais/farmacologia , Inibidores Enzimáticos/farmacologia , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica , Quinazolinonas/farmacologia , Relação Estrutura-Atividade , Proteínas não Estruturais Virais , Replicação Viral
3.
Bioorg Med Chem Lett ; 61: 128605, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35123007

RESUMO

Nucleoside analogues represent an historically accomplished class of antiviral drug. Notwithstanding this, new molecular scaffolds are required to overcome their limitations and evolve pharmacophore space within this established field. Herein, we develop concise synthetic access to a new 2'-deoxy-2'-fluoro-2'-C-methyl-4'-thionucleoside chemotype, including the ProTide form of the uridine analogue. Biological evaluation of these materials in the Hepatitis C replicon assay shows little activity for the canonical pyrimidine forms, but the phosphoramidate of 2'-deoxy-2'-fluoro-2'-C-methyl-ß-d-4'-thiouridine has an EC50 of 2.99 µM. Direct comparison to the established Hepatitis C drug Sofosbuvir shows a 100-fold drop in activity upon substituting the furanose chalcogen; the reasons for this are as yet unclear.


Assuntos
Antivirais/farmacologia , Desenho de Fármacos , Hepacivirus/efeitos dos fármacos , Tionucleosídeos/farmacologia , Antivirais/síntese química , Antivirais/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Tionucleosídeos/síntese química , Tionucleosídeos/química , Replicação Viral/efeitos dos fármacos
4.
J Gen Virol ; 103(2)2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35133954

RESUMO

Drug resistance mutations of hepatitis C virus (HCV) negatively impact viral replicative fitness. RNA viruses are known to change their replication behaviour when subjected to suboptimal selection pressure. Here, we assess whether mutation supply in HCV is sufficiently large to allow the selection of its variants during dual or triple direct-acting antiviral (DAA) treatment associated with augmented virus fitness or impairment. We engineered randomly mutagenized full-genome libraries to create a highly diverse population of replication-competent HCV variants in cell culture. These variants exhibited escape when treated with NS5A/NS5B inhibitors (daclatasvir/sofosbuvir), and relapse on treatment with a combination of NS3/NS5A/NS5B inhibitors (simeprevir or paritaprevir/daclatasvir/sofosbuvir). Analysis of the relationship between virus fitness and drug resistance of JFH1-derived NS5A-5B variants showed a significant positive correlation (P=0.003). At the earliest time points, intracellular RNA levels remain unchanged in both the subgenomic replicon and infection assays, whereas extracellular RNA levels increased upto ten-fold compared to wild-type JFH1. Beneficial substitutions hyperstimulated phosphatidylinositol 4-phosphate during DAA treatment, and showed decreased dependence on cyclophilins during cyclosporine A treatment, indicating an interplay of virus-host molecular mechanisms in beneficial substitution selection that may necessitate infectious virus production. This comprehensive study demonstrates a possible role for HCV fitness of overcoming drug-mediated selection pressure.


Assuntos
Antivirais/farmacologia , Farmacorresistência Viral/efeitos dos fármacos , Hepacivirus , Hepatite C , Quimioterapia Combinada , Hepacivirus/efeitos dos fármacos , Hepacivirus/crescimento & desenvolvimento , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Humanos
5.
Viruses ; 14(2)2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35215901

RESUMO

A hepatitis C virus (HCV) screening and treatment program was conducted in Hungarian prisons on a voluntary basis. After HCV-RNA testing and genotyping for anti-HCV positives, treatments with direct-acting antiviral agents were commenced by hepatologists who visited the institutions monthly. Patients were supervised by the prisons' medical staff. Data were retrospectively collected from the Hungarian Hepatitis Treatment Registry, from the Health Registry of Prisons, and from participating hepatologists. Eighty-four percent of Hungarian prisons participated, meaning a total of 5779 individuals (28% of the inmate population) underwent screening. HCV-RNA positivity was confirmed in 317/5779 cases (5.49%); 261/317 (82.3%) started treatment. Ninety-nine percent of them admitted previous intravenous drug use. So far, 220 patients received full treatment and 41 patients are still on treatment. Based on the available end of treatment (EOT) + 24 weeks timepoint data, per protocol sustained virologic response rate was 96.8%. In conclusion, the Hungarian prison screening and treatment program, with the active participation of hepatologists and the prisons' medical staff, is a well-functioning model. Through the Hungarian experience, we emphasize that the "test-and-treat" principle is feasible and effective at micro-eliminating HCV in prisons, where infection rate, as well as history of intravenous drug usage, are high.


Assuntos
Antivirais/administração & dosagem , Hepacivirus/isolamento & purificação , Hepatite C/tratamento farmacológico , Adolescente , Adulto , Feminino , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/sangue , Hepatite C/diagnóstico , Hepatite C/virologia , Humanos , Hungria , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Prisões/estatística & dados numéricos , Estudos Retrospectivos , Resposta Viral Sustentada , Adulto Jovem
6.
Viruses ; 14(2)2022 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-35215955

RESUMO

Background: The results of long-term renal evolution in HCV-infected patients using sofosbuvir and velpatasvir (SOF/VEL), with or without ribavirin (RBV), are lacking. Aims: We evaluated the renal safety for HCV-infected patients receiving SOF/VEL. Methods: Between 1 June 2019 and 6 July 2020, we included 594 HCV-infected patients receiving SOF/VEL +/- RBV for 12 weeks in Taiwan. Viral eradication rate (defined by sustained virological response at week 12 post-treatment; SVR12) and changes to renal function were considered. Results: SVR12 was achieved in 99.3% (590/594) upon per-protocol analysis. Patients saw improved hepatobiliary function and fibrosis after the start of SOF/VEL therapy. For renal function, those with baseline estimated glomerular filtration rate (eGFR) ≥ 60 (mL/min/1.73 m2) experienced transient on-treatment reduction in renal function that improved upon ending treatment, but recurrent eGFR degradation during one-year follow-up. The use of RBV (OR = 5.200, 95% CI: 1.983-13.634, p = 0.001) was a significant risk factor at SVR24, while diabetes mellitus (OR = 2.765, 95% CI: 1.104-6.922, p = 0.030) and the use of RBV (OR = 3.143, 95% CI: 1.047-9.435, p = 0.041) were identified as significant risk factors of worsening renal function at SVR48. SOF/VEL did not worsen renal function among those with stage 4-5 chronic kidney disease (CKD) who were not receiving dialysis. Conclusions: A trend of decline in eGFR at 1 year after SOF/VEL treatment was observed among diabetic patients with baseline eGFR ≥ 60 (mL/min/1.73 m2) and concomitant use of RBV. The close monitoring of renal function is warranted. Further study should be conducted in order to weigh the risks and benefit of RBV.


Assuntos
Antivirais/uso terapêutico , Carbamatos/uso terapêutico , Taxa de Filtração Glomerular/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Sofosbuvir/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Combinação de Medicamentos , Feminino , Seguimentos , Taxa de Filtração Glomerular/fisiologia , Hepacivirus/efeitos dos fármacos , Hepatite C/mortalidade , Hepatite C/fisiopatologia , Humanos , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/mortalidade , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Ribavirina/uso terapêutico , Fatores de Risco , Resposta Viral Sustentada , Taiwan/epidemiologia , Adulto Jovem
7.
Molecules ; 27(3)2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35164341

RESUMO

Terminalia chebula Retz. forms a key component of traditional folk medicine and is also reported to possess antihepatitis C virus (HCV) and immunomodulatory activities. However, information on the intermolecular interactions of phytochemicals from this plant with HCV and human proteins are yet to be established. Thus, by this current study, we investigated the HCV NS3/4A inhibitory and host immune-modulatory activity of phytocompounds from T. chebula through in silico strategies involving network pharmacology and structural bioinformatics techniques. To start with, the phytochemical dataset of T. chebula was curated from biological databases and the published literature. Further, the target ability of the phytocompounds was predicted using BindingDB for both HCV NS3/4A and other probable host targets involved in the immune system. Further, the identified targets were docked to the phytochemical dataset using AutoDock Vina executed through the POAP pipeline. The resultant docked complexes with significant binding energy were subjected to 50 ns molecular dynamics (MD) simulation in order to infer the stability of complex formation. During network pharmacology analysis, the gene set pathway enrichment of host targets was performed using the STRING and Reactome pathway databases. Further, the biological network among compounds, proteins, and pathways was constructed using Cytoscape 3.6.1. Furthermore, the druglikeness, side effects, and toxicity of the phytocompounds were also predicted using the MolSoft, ADVERpred, and PreADMET methods, respectively. Out of 41 selected compounds, 10 were predicted to target HCV NS3/4A and also to possess druglike and nontoxic properties. Among these 10 molecules, Chebulagic acid and 1,2,3,4,6-Pentagalloyl glucose exhibited potent HCV NS3/4A inhibitory activity, as these scored a lowest binding energy (BE) of -8.6 kcal/mol and -7.7 kcal/mol with 11 and 20 intermolecular interactions with active site residues, respectively. These findings are highly comparable with Asunaprevir (known inhibitor of HCV NS3/4A), which scored a BE of -7.4 kcal/mol with 20 key intermolecular interactions. MD studies also strongly suggest that chebulagic acid and 1,2,3,4,6-Pentagalloyl glucose as promising leads, as these molecules showed stable binding during 50 ns of production run. Further, the gene set enrichment and network analysis of 18 protein targets prioritized 10 compounds and were predicted to potentially modulate the host immune system, hemostasis, cytokine levels, interleukins signaling pathways, and platelet aggregation. On overall analysis, this present study predicts that tannins from T. chebula have a potential HCV NS3/4A inhibitory and host immune-modulatory activity. However, further experimental studies are required to confirm the efficacies.


Assuntos
Antivirais/farmacologia , Hepacivirus/enzimologia , Serina Proteases/química , Serina Proteases/metabolismo , Taninos/farmacologia , Terminalia/química , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo , Antivirais/efeitos adversos , Antivirais/química , Benzopiranos/farmacologia , Domínio Catalítico , Simulação por Computador , Glucosídeos/farmacologia , Hepacivirus/efeitos dos fármacos , Taninos Hidrolisáveis/farmacologia , Modelos Moleculares , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Farmacologia em Rede , Extratos Vegetais/farmacologia , Ligação Proteica , Conformação Proteica , Taninos/efeitos adversos , Taninos/química , Proteínas não Estruturais Virais/antagonistas & inibidores
8.
J Mol Biol ; 434(9): 167503, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35183560

RESUMO

Third generation Hepatitis C virus (HCV) NS3/4A protease inhibitors (PIs), glecaprevir and voxilaprevir, are highly effective across genotypes and against many resistant variants. Unlike earlier PIs, these compounds have fluorine substitutions on the P2-P4 macrocycle and P1 moieties. Fluorination has long been used in medicinal chemistry as a strategy to improve physicochemical properties and potency. However, the molecular basis by which fluorination improves potency and resistance profile of HCV NS3/4A PIs is not well understood. To systematically analyze the contribution of fluorine substitutions to inhibitor potency and resistance profile, we used a multi-disciplinary approach involving inhibitor design and synthesis, enzyme inhibition assays, co-crystallography, and structural analysis. A panel of inhibitors in matched pairs were designed with and without P4 cap fluorination, tested against WT protease and the D168A resistant variant, and a total of 22 high-resolution co-crystal structures were determined. While fluorination did not significantly improve potency against the WT protease, PIs with fluorinated P4 caps retained much better potency against the D168A protease variant. Detailed analysis of the co-crystal structures revealed that PIs with fluorinated P4 caps can sample alternate binding conformations that enable adapting to structural changes induced by the D168A substitution. Our results elucidate molecular mechanisms of fluorine-specific inhibitor interactions that can be leveraged in avoiding drug resistance.


Assuntos
Ácidos Aminoisobutíricos , Ciclopropanos , Desenho de Fármacos , Farmacorresistência Viral , Inibidores da HCV NS3-4A Protease , Lactamas Macrocíclicas , Leucina/análogos & derivados , Prolina/análogos & derivados , Quinoxalinas , Sulfonamidas , Proteases Virais , Ácidos Aminoisobutíricos/química , Ácidos Aminoisobutíricos/farmacologia , Ciclopropanos/química , Ciclopropanos/farmacologia , Farmacorresistência Viral/genética , Flúor/química , Inibidores da HCV NS3-4A Protease/química , Inibidores da HCV NS3-4A Protease/farmacologia , Halogenação , Hepacivirus/efeitos dos fármacos , Hepacivirus/enzimologia , Hepacivirus/genética , Humanos , Lactamas Macrocíclicas/química , Lactamas Macrocíclicas/farmacologia , Leucina/química , Leucina/genética , Leucina/farmacologia , Prolina/química , Prolina/genética , Prolina/farmacologia , Quinoxalinas/química , Quinoxalinas/farmacologia , Sulfonamidas/química , Sulfonamidas/farmacologia , Proteases Virais/química , Proteases Virais/genética
9.
PLoS One ; 17(1): e0262267, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35020772

RESUMO

BACKGROUND: The features of hepatitis C virus patients with a sustained virologic response (SVR) who developed hepatocellular carcinoma (HCC) after direct-acting antiviral (DAA) therapy are unclear. METHODS: The study population included 1494 DAA-SVR patients without a history of HCC. The cumulative carcinogenesis rate after the end of treatment (EOT) and factors related to HCC were analyzed. RESULTS: Sixty (4.0%) patients developed HCC during a median observation period of 47.6 months. At four years, the cumulative carcinogenesis rate was 4.7%. A Cox proportional hazards analysis showed that age ≥73 years (hazard ratio [HR]: 2.148), male sex (HR: 3.060), hyaluronic acid (HA) ≥75 ng/mL (HR: 3.996), alpha-fetoprotein at EOT (EOT-AFP) ≥5.3 ng/mL (HR: 4.773), and albumin at EOT (EOT-Alb) <3.9 g/dL (HR: 2.305) were associated with HCC development. Especially, EOT-AFP ≥5.3 ng/mL was associated with HCC development after 3 years from EOT (HR: 6.237). Among patients who developed HCC, AFP did not increase in patients with EOT-AFP <5.3 ng/mL at the onset of HCC. Of these 5 factors, EOT-AFP ≥5.3 ng/mL was scored as 2 points; the others were scored as 1 point. The 4-year cumulative carcinogenesis rate for patients with total scores of 0-2, 3-4, and 5-6 points were 0.6%, 11.9%, and 27.1%, respectively (p<0.001). CONCLUSIONS: EOT-AFP ≥5.3 ng/mL is useful for predicting HCC development after an SVR. However, AFP does not increase in patients with EOT-AFP <5.3 ng/mL at the onset of HCC. The combination of EOT-AFP, age, sex, HA, and EOT-Alb is important for predicting carcinogenesis.


Assuntos
Antivirais/efeitos adversos , Carcinoma Hepatocelular/patologia , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Neoplasias Hepáticas/patologia , Idoso , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/virologia , Feminino , Seguimentos , Hepatite C Crônica/virologia , Humanos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/virologia , Masculino , Prognóstico , Estudos Prospectivos , Fatores de Risco , Taxa de Sobrevida
10.
Viruses ; 14(1)2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-35062302

RESUMO

Difficult-to-treat populations with chronic hepatitis C (CHC), in the era of interferon treatment, included patients with liver cirrhosis, kidney impairment, treatment-experienced individuals, and those coinfected with the human immunodeficiency virus. The current study aimed to determine whether, in the era of direct-acting antivirals (DAA), there are still patients that are difficult-to-treat. The study included all consecutive patients chronically infected with hepatitis C virus (HCV) who started interferon-free therapy between July 2015 and December 2020 in the Department of Infectious Diseases in Kielce. The analyzed real-world population consisted of 963 patients, and most of them were infected with genotype 1 (87.6%) with the predominance of subtype 1b and were treatment-naïve (78.8%). Liver cirrhosis was determined in 207 individuals (21.5%), of whom 82.6% were compensated. The overall sustained virologic response, after exclusion of non-virologic failures, was achieved in 98.4%. The univariable analysis demonstrated the significantly lower response rates in males, patients with liver cirrhosis, decompensation of hepatic function at baseline, documented esophageal varices, concomitant diabetes, body mass index ≥25, and previous ineffective antiviral treatment. Despite an overall very high effectiveness, some unfavorable factors, including male gender, genotype 3 infection, liver cirrhosis, and treatment experience, significantly reduce the chances for a virologic response were identified.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Coinfecção , Quimioterapia Combinada , Feminino , Genótipo , Infecções por HIV/complicações , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Hepatite B/complicações , Hepatite C Crônica/complicações , Hepatite C Crônica/virologia , Humanos , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Resposta Viral Sustentada , Falha de Tratamento , Resultado do Tratamento , Adulto Jovem
11.
J Nat Prod ; 85(1): 284-291, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-34967639

RESUMO

We have previously reported that neoechinulin B (1a), a prenylated indole diketopiperazine alkaloid, shows antiviral activities against hepatitis C virus (HCV) via the inactivation of the liver X receptors (LXRs) and the resultant disruption of double-membrane vesicles. In this study, a two-step synthesis of the diketopiperazine scaffold of 1a was achieved by the base-induced coupling of 1,4-diacetyl-3-{[(tert-butyldimethylsilyl)oxy]methyl}piperazine-2,5-dione with aldehydes, followed by the treatment of the resultant coupling products with tetra-n-butylammonium fluoride. Compound 1a and its 16 derivatives 1b-q were prepared using this method. Furthermore, variecolorin H, a related alkaloid, was obtained by the acid treatment of 1a in MeOH. The antiviral evaluation of 1a and its derivatives revealed that 1a, 1c, 1d, 1h, 1j, 1l, and 1o exhibited both anti-HCV and anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) activities. The results of this study indicate that the exomethylene moiety on the diketopiperazine ring is important for the antiviral activities. The antiviral compounds can inhibit the production of HCV and SARS-CoV-2 by inactivating LXRs.


Assuntos
Alcaloides/farmacologia , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Piperazinas/farmacologia , SARS-CoV-2/efeitos dos fármacos , Alcaloides/síntese química , Alcaloides/química , Antivirais/síntese química , Antivirais/química , Linhagem Celular Tumoral , Dicetopiperazinas/química , Dicetopiperazinas/farmacologia , Humanos , Receptores X do Fígado/antagonistas & inibidores , Estrutura Molecular , Piperazinas/síntese química , Piperazinas/química , Relação Estrutura-Atividade , Transcrição Gênica/efeitos dos fármacos
12.
J Biol Chem ; 298(2): 101529, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34953856

RESUMO

Remdesivir (RDV) is a direct-acting antiviral agent that is approved in several countries for the treatment of coronavirus disease 2019 caused by the severe acute respiratory syndrome coronavirus 2. RDV exhibits broad-spectrum antiviral activity against positive-sense RNA viruses, for example, severe acute respiratory syndrome coronavirus and hepatitis C virus, and nonsegmented negative-sense RNA viruses, for example, Nipah virus, whereas segmented negative-sense RNA viruses such as influenza virus or Crimean-Congo hemorrhagic fever virus are not sensitive to the drug. The reasons for this apparent efficacy pattern are unknown. Here, we expressed and purified representative RNA-dependent RNA polymerases and studied three biochemical parameters that have been associated with the inhibitory effects of RDV-triphosphate (TP): (i) selective incorporation of the nucleotide substrate RDV-TP, (ii) the effect of the incorporated RDV-monophosphate (MP) on primer extension, and (iii) the effect of RDV-MP in the template during incorporation of the complementary UTP. We found a strong correlation between antiviral effects and efficient incorporation of RDV-TP. Inhibition in primer extension reactions was heterogeneous and usually inefficient at higher NTP concentrations. In contrast, template-dependent inhibition of UTP incorporation opposite the embedded RDV-MP was seen with all polymerases. Molecular modeling suggests a steric conflict between the 1'-cyano group of the inhibitor and residues of the structurally conserved RNA-dependent RNA polymerase motif F. We conclude that future efforts in the development of nucleotide analogs with a broader spectrum of antiviral activities should focus on improving rates of incorporation while capitalizing on the inhibitory effects of a bulky 1'-modification.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Modelos Moleculares , Vírus de RNA/enzimologia , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Monofosfato de Adenosina/química , Monofosfato de Adenosina/farmacologia , Alanina/química , Alanina/farmacologia , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Hepacivirus/enzimologia , Vírus de RNA de Sentido Negativo/efeitos dos fármacos , Vírus de RNA de Sentido Negativo/enzimologia , Vírus Nipah/efeitos dos fármacos , Vírus Nipah/enzimologia , Vírus de RNA de Cadeia Positiva/efeitos dos fármacos , Vírus de RNA de Cadeia Positiva/enzimologia , Vírus de RNA/efeitos dos fármacos , RNA Viral/metabolismo , RNA Polimerase Dependente de RNA/química , RNA Polimerase Dependente de RNA/metabolismo , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia , Replicação Viral/efeitos dos fármacos
13.
Eur J Med Chem ; 228: 114033, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34883293

RESUMO

A series of novel biaryl amide derivatives were synthesized and evaluated for anti-HCV virus activity. Some significant SARs were uncovered. The intensive structural modifications led to fifteen novel compounds with more potent inhibitory activity compared to the hit compounds IMB 26 and IMB1f. Among them, compound 80 was the most active, with EC50 values almost equivalent to the clinical drug telaprevir (EC50 = 15 nM). Furthermore, it also had a good safety and in vitro and oral pharmacokinetic (oral bioavailability in rats: 34%) profile, suggesting a highly drug-like nature. Compound 80represents a more promising scaffold for anti-HCV virus activity for further study.


Assuntos
Amidas/farmacologia , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Amidas/síntese química , Amidas/química , Antivirais/síntese química , Antivirais/química , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade
14.
Antiviral Res ; 197: 105224, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34864126

RESUMO

Despite the excellent antiviral potency of direct-acting antivirals (DAAs) against hepatitis C virus (HCV), emergence of drug-resistant viral mutations remains a potential challenge. Sofobuvir (SOF), a nucleotide analog targeting HCV NS5B - RNA-dependent RNA polymerase (RdRp), constitutes a key component of many anti-HCV cocktail regimens and confers a high barrier for developing drug resistance. The serine to threonine mutation at the amino acid position 282 of NS5B (S282T) is the mostly documented SOF resistance-associated substitution (RAS), but severely hampers the virus fitness. In this study, we first developed new genotype 1b (GT1b) subgenomic replicon cells, denoted PR52D4 and PR52D9, directly from a GT1b clinical isolate. Next, we obtained SOF-resistant and replication-competent PR52D4 replicon by culturing the replicon cells in the presence of SOF. Sequencing analysis showed that the selected replicon harbored two mutations K74R and S282T in NS5B. Reverse genetics analysis showed that while PR52D4 consisting of either single mutation K74R or S282T could not replicate efficiently, the engineering of the both mutations led to a replication-competent and SOF-resistant PR52D4 replicon. Furthermore, we showed that the K74R mutation could also rescue the replication deficiency of the S282T mutation in Con1, another GT1b replicon as well as in JFH1, a GT2a replicon. Structural modeling analysis suggested that K74R might help maintain an active catalytic conformation of S282T by engaging with Y296. In conclusion, we identified the combination of two NS5B mutations S282T and K74R as a novel RAS that confers a substantial resistance to SOF while retains the HCV replication capacity.


Assuntos
Antivirais/farmacologia , Farmacorresistência Viral/genética , Variação Genética , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Replicon/genética , Sofosbuvir/farmacologia , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C/virologia , Humanos , Replicon/efeitos dos fármacos
15.
J Med Virol ; 94(2): 675-682, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34599755

RESUMO

Treatment of hepatitis C virus (HCV) infection with direct-acting antiviral agents (DAAs) in hemodialysis patients requires extensive consideration. At present, studies regarding DAAs for acute HCV infection in such patients are limited. The present study aims to evaluate the efficacy and safety of grazoprevir (GZR) plus elbasvir (EBR) treatment in acute hepatitis C (AHC) patients undergoing hemodialysis. Patients undergoing hemodialysis who had a nosocomial acute HCV infection were enrolled. All patients received GZR 100 mg/EBR 50 mg once daily for 12 weeks and were followed up for 12 weeks. Serum alanine transaminase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), and HCV RNA levels were monitored during treatment and follow-up periods. Sustained virologic response at 12 weeks after treatment cessation and treatment-emergent adverse events (AEs) were assessed. A total of 68 AHC patients were enrolled. All patients were infected with HCV genotype 1b and achieved SVR12. Decreasing ALT, AST, and TBIL were observed over time in the first 4 weeks and became steady thereafter. Forty-eight (70.59%) patients reported at least one AEs. The most common AEs were fatigue, headache, and nausea. Two AHC patients discontinued treatment due to serious but drug-unrelated AEs. In conclusion, GZR/EBR has a high efficacy and safety profile in hemodialysis-dependent patients with genotype 1b AHC.


Assuntos
Antivirais/uso terapêutico , Benzofuranos/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Imidazóis/uso terapêutico , Quinoxalinas/uso terapêutico , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Combinação de Medicamentos , Feminino , Genótipo , Hepacivirus/genética , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Diálise Renal/efeitos adversos , Estudos Retrospectivos , Resposta Viral Sustentada
16.
Gut ; 71(3): 627-642, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33833066

RESUMO

OBJECTIVE: HCV-genotype 4 infections are a major cause of liver diseases in the Middle East/Africa with certain subtypes associated with increased risk of direct-acting antiviral (DAA) treatment failures. We aimed at developing infectious genotype 4 cell culture systems to understand the evolutionary genetic landscapes of antiviral resistance, which can help preserve the future efficacy of DAA-based therapy. DESIGN: HCV recombinants were tested in liver-derived cells. Long-term coculture with DAAs served to induce antiviral-resistance phenotypes. Next-generation sequencing (NGS) of the entire HCV-coding sequence identified mutation networks. Resistance-associated substitutions (RAS) were studied using reverse-genetics. RESULT: The in-vivo infectious ED43(4a) clone was adapted in Huh7.5 cells, using substitutions identified in ED43(Core-NS5A)/JFH1-chimeric viruses combined with selected NS5B-changes. NGS, and linkage analysis, permitted identification of multiple genetic branches emerging during culture adaptation, one of which had 31 substitutions leading to robust replication/propagation. Treatment of culture-adapted ED43 with nine clinically relevant protease-DAA, NS5A-DAA and NS5B-DAA led to complex dynamics of drug-target-specific RAS with coselection of genome-wide substitutions. Approved DAA combinations were efficient against the original virus, but not against variants with RAS in corresponding drug targets. However, retreatment with glecaprevir/pibrentasvir remained efficient against NS5A inhibitor and sofosbuvir resistant variants. Recombinants with specific RAS at NS3-156, NS5A-28, 30, 31 and 93 and NS5B-282 were viable, but NS3-A156M and NS5A-L30Δ (deletion) led to attenuated phenotypes. CONCLUSION: Rapidly emerging complex evolutionary landscapes of mutations define the persistence of HCV-RASs conferring resistance levels leading to treatment failure in genotype 4. The high barrier to resistance of glecaprevir/pibrentasvir could prevent persistence and propagation of antiviral resistance.


Assuntos
Antivirais/farmacologia , Farmacorresistência Viral/genética , Hepacivirus/efeitos dos fármacos , Hepacivirus/fisiologia , Hepatócitos/virologia , Mutação/genética , Benzimidazóis/farmacologia , Técnicas de Cultura de Células , Combinação de Medicamentos , Genótipo , Hepacivirus/genética , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Humanos , Pirrolidinas/farmacologia , Quinoxalinas/farmacologia , Sofosbuvir/farmacologia , Sulfonamidas/farmacologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-33550979

RESUMO

BACKGROUND AND AIM: Eradication of hepatitis C virus (HCV) by direct-acting-antiviral- agents (DAAs) was followed by fibrosis regression, but little is available about hepatic steatosis changes after DAAs. The aim of this work was to assess the prevalence of hepatic steatosis among HCV Egyptian patients and the long term changes occuring after viral eradication. METHODS: This prospective cohort study included 150 HCV patients with significant fibrosis. They were examined by Transient elastography to evaluate liver stiffness measurement (LSM) and hepatic steatosis before treatment, at SVR12 and 1 year after the end of therapy. RESULTS: LSM showed a significant positive correlation to pretreatment of hepatic steatosis. LSM significantly decreased and hepatic steatosis significantly increased both at SVR12 and one year after DAAs. Patients with steatosis showed significantly higher median LSM and controlled attenuation parameter (CAP) values at: baseline, SVR12, and one year after therapy. Also, the pretreatment steatosis and body mass index (BMI) had a significant negative correlation with fibrosis regression one year after therapy in all studied groups. CONCLUSION: Hepatic steatosis is common in HCV Egyptian patients and increases after HCV eradication with DAAs. BMI and CAP values are negatively correlated to hepatic fibrosis regression and positively correlated to steatosis progression one year after DAAs. So, HCV patients with hepatic steatosis may need close follow up for atherosclerotic and HCC risk after DAAs, especially if they are overweight.


Assuntos
Antivirais/uso terapêutico , Fígado Gorduroso/diagnóstico , Fígado Gorduroso/tratamento farmacológico , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Adulto , Antivirais/farmacologia , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Egito/epidemiologia , Técnicas de Imagem por Elasticidade , Fígado Gorduroso/epidemiologia , Fígado Gorduroso/virologia , Feminino , Hepacivirus/fisiologia , Hepatite C/complicações , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Humanos , Cirrose Hepática/diagnóstico , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/epidemiologia , Cirrose Hepática/virologia , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco , Resultado do Tratamento
18.
J Hepatol ; 76(2): 302-310, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34592366

RESUMO

BACKGROUND & AIMS: As the long-term benefits of a sustained virological response (SVR) in HCV-related cirrhosis following direct-acting antiviral (DAA) treatment remain undefined, we assessed the incidence and predictors of liver-related events (LREs), non-liver-related events (NLREs) and mortality in DAA-treated patients with cirrhosis. METHODS: Consecutive patients with cirrhosis and SVR were enrolled in a longitudinal, single-center study, and divided into 3 cohorts: Cohort A (Child-Pugh A without a previous LRE), Cohort B (Child-Pugh B or Child-Pugh A with prior non-hepatocellular carcinoma [HCC] LREs), Cohort C (previous HCC). RESULTS: A total of 636 patients with cirrhosis (median 65 years-old, 58% males, 89% Child-Pugh A) were followed for 51 (8-68) months (Cohort A n = 480, Cohort B n = 89, Cohort C n = 67). The 5-year estimated cumulative incidences of LREs were 10.4% in Cohort A vs. 32.0% in Cohort B (HCC 7.7% vs. 19.7%; ascites 1.4% vs. 8.6%; variceal bleeding 1.3% vs. 7.8%; encephalopathy 0 vs. 2.5%) vs. 71% in Cohort C (HCC only) (p <0.0001). The corresponding figures for NLREs were 11.7% in Cohort A vs. 17.9% in Cohort B vs. 17.5% in Cohort C (p = 0.32). The 5-year estimated probabilities of liver-related vs. non-liver-related deaths were 0.5% vs. 4.5% in Cohort A, 16.2% vs. 8.8% in Cohort B and 12.1% vs. 7.7% in Cohort C. The all-cause mortality rate in Cohort A was similar to the rate expected for the general population stratified by age, sex and calendar year according to the Human Mortality Database, while it was significantly higher in Cohort B. CONCLUSIONS: Patients with cirrhosis and an SVR on DAAs face risks of liver-related and non-liver-related events and mortality; however, their incidence is strongly influenced by pre-DAA patient history. LAY SUMMARY: In this large single-center study enrolling patients with hepatitis C virus (HCV)-related cirrhosis cured by direct-acting antivirals, pre-treatment liver disease history strongly influenced long-term outcomes. In patients with HCV-related cirrhosis, hepatocellular carcinoma was the most frequent liver-related complication after viral cure. Due to improved long-term outcomes, patients with cirrhosis after HCV cure are exposed to a significant proportion of non-liver-related events.


Assuntos
Hepatite C/complicações , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Resposta Viral Sustentada , Idoso , Antivirais/uso terapêutico , Distribuição de Qui-Quadrado , Estudos de Coortes , Feminino , Hepacivirus/efeitos dos fármacos , Hepacivirus/patogenicidade , Hepatite C/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/métodos , Modelos de Riscos Proporcionais
19.
Ann Hepatol ; 27(1): 100545, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34571264

RESUMO

INTRODUCTION AND OBJECTIVES: Hepatitis C virus (HCV) infections in patients with hemophilia lead to the development of hepatocellular carcinoma (HCC) at a relatively younger age than that in patients without hemophilia. Although recent progress in direct-acting-antivirals has facilitated a high rate of sustained virological response (SVR), the clinical influence of HCV eradication in hemophilia patients remains unclear. This study aimed to compare the clinical outcomes of SVR against HCV in patients with and without hemophilia. PATIENTS AND METHODS: The study enrolled 699 patients who achieved SVR after HCV antiviral treatment. Patients were divided into two groups: 78 patients with hemophilia (H group) and 621 patients without hemophilia (NH group). We evaluated patient characteristics, clinical outcomes, and the cumulative incidence of HCC after SVR. RESULTS: Compared with the NH group, patients in the H-group were significantly younger and had a lower hepatic fibrosis score. No difference was found in the incidence of liver-related disease or overall death between the two groups over a mean follow-up period of 7 years. Four patients in the H group and 36 patients in the NH group were diagnosed with HCC after SVR. Multivariate analysis showed that male sex, age, and cirrhosis were significant risk factors for HCC incidence. There was no significant difference in the cumulative incidence of HCC after propensity-score matching adjusting for the risk factors of HCC between the two groups. CONCLUSION: Hemophilia is not a significant risk factor for hepatocarcinogenesis after SVR against HCV.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Hemofilia A/complicações , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Adulto , Idoso , Antivirais/uso terapêutico , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , Feminino , Seguimentos , Hepatite C/complicações , Hepatite C/epidemiologia , Humanos , Incidência , Japão/epidemiologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
20.
Isr Med Assoc J ; 23(12): 794-800, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34954919

RESUMO

BACKGROUND: New direct acting antiviral agent (DAA) therapies are associated with a high sustained virological response rate (SVR) in hepatitis C virus (HCV) patients. The understanding of the impact of SVR on fibrosis stage is limited. OBJECTIVES: To determine the effect of treatment with the DAAs on long-term liver fibrosis stages, as determined by shear-wave elastography (SWE) or FibroTest. METHODS: Fibrosis stage was determined at baseline and at 6-month intervals after end of treatment (EOT), using two-dimensional SWE or FibroTest©; APRI and FIB-4 scores. RESULTS: The study comprised 133 SVR12 patients. After a median follow-up of 15 months (range 6-33), liver fibrosis stage decreased by at least 1 stage in 75/133 patients (56%). Cirrhosis reversal was observed in 24/82 (29%). Repeated median liver stiffness SWE values in cirrhotic patients were 15.1 kPa at baseline (range 10.5-100), 13.4 kPa (range 5.5-51) at 6 months, and 11.4 kPa (range 6.1-35.8) at 12 months after EOT, P = 0.01. During the second year after EOT, no statistically significant differences in liver fibrosis stage in 12, 18, and 24 months were found. Splenomegaly was the only significant negative predictor of liver fibrosis regression during all time points of repetitive noninvasive assessment. CONCLUSIONS: Following successful DAA treatment, the majority of our HCV patients with advanced fibrosis demonstrated significant improvement, as assessed by non-invasive methods. Advanced fibrosis stage was a negative predictor of fibrosis regression. Longer follow-up periods are required to further establish the impact of DAAs treatment in HCV patients with advanced fibrosis.


Assuntos
Antivirais/administração & dosagem , Hepatite C Crônica/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas de Imagem por Elasticidade , Feminino , Seguimentos , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/complicações , Humanos , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Esplenomegalia/epidemiologia , Resposta Viral Sustentada , Fatores de Tempo , Resultado do Tratamento
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