Hepatitis C Virus Genotype 1a Research Articles

Molecular characterization of the nonstructural 5A (NS5A) region of hepatitis C virus in Thai blood donors.

Direct acting antivirals (DAAs) have been developed for hepatitis C virus (HCV) therapy, and they are usually effective, however resistance to DAA regimens has also been reported to have a significant impact. Resistance associated substitutions (RASs) in the NS5A region are known to be correlated with failure of DAA therapy. HCV genotypes 3a and 1 are the most prevalent genotypes in Thailand. This study analyzed the type and frequency of RASs associated with DAA failure, focusing on the NS5A region. Serum samples of HCV genotype 3a, 1a, and 1b infection from Thai blood donors were selected. The NS5A region was amplified using reverse transcription-polymerase chain reaction (RT-PCR). A phylogenetic tree was constructed to identify the genotypes of HCV. Nucleotide sequencing and amino acid sequencing were conducted to determine the prevalence of RASs. Construction of the phylogenetic tree indicated that 29 samples were genotype 3a, 11 samples were genotype 1a, and 9 were genotype 1b. Both HCV genotypes 1a and 3a can be categorized into two subclades. Results showed that the NS5A substitutions A30V/K, A62T/V/I/M/P/S/L, and S98G were present in HCV genotype 3a. In HCV genotype 1a, only NS5A RASs H54Y was detected. NS5A amino acid substitutions Q54H and P58L were found in HCV genotype 1b. In conclusion, NS5A RASs at amino acid positions 30, 62, 54, 58, and 98 are present within HCV genotypes 3a and 1. While keeping in mind that additional information was not available on the anonymous blood donors tested in this study, these findings can contribute to understand the NS5A mutation. Further study with known patients under drug treatment is recommended.

Improvement in Thrombocytopenia after Direct Acting Anti-Viral (DAA)Therapy in Patients with Hepatitis C Virus-Related Chronic Liver Disease in Pakistani Population-A Single Centered Study

Background: Hepatitis C Virus (HCV) infection remains a significant global health challenge, often leading to chronic liver diseases such as cirrhosis and associated complications like thrombocytopenia. Directly acting antivirals (DAAs) have revolutionized HCV treatment due to their high efficacy and favorable safety profiles but the impact on thrombocytopenia, particularly in the Pakistani population, has been less studied. Objective: This study aimed to evaluate the effects of DAA therapy on platelet count and other laboratory parameters in chronic HCV patients with thrombocytopenia in Pakistan and to establish correlations between treatment outcomes and baseline laboratory values. Methods: A retrospective observational study was conducted at the Sindh Institute of Urology and Transplantation from January 2018 to December 2022. Patients with chronic HCV genotype 3a infection, compensated cirrhosis, and a baseline platelet count of less than 150 × 10^9/L were included. Exclusion criteria encompassed decompensated liver disease, liver cancer, and other specific conditions. The treatment regimens were Sofosbuvir plus Daclatasvir or Velpatasvir plus Ribavirin over three months. Parameters such as complete blood counts, serum creatinine, liver enzymes, and Child-Turcotte-Pugh (CTP) and Model for End-Stage Liver Disease (MELD) scores were recorded at baseline and post-treatment. Statistical analysis was performed using SPSS version 25, employing paired t-tests and Pearson correlation coefficients. Results: A total of 195 patients were studied, with a mean baseline platelet count of 100.7 × 10^9/L, which significantly increased to 122.2 × 10^9/L post-treatment (p < 0.001). Improvements were also noted in mean serum creatinine (0.96 mg/dL to 0.87 mg/dL; p = 0.009), total bilirubin (1.6 mg/dL to 1.2 mg/dL; p < 0.001), liver enzymes (ALT from 63.9 IU to 45.9 IU; p < 0.001 and AST from 86.8 IU to 59.5 IU; p < 0.001), and MELD scores (11.5 to 9.3; p < 0.001). Hemoglobin levels and total leukocyte counts also showed significant improvements. Conclusion: DAA therapy significantly improves platelet counts and other laboratory parameters in chronic HCV patients with thrombocytopenia, suggesting a positive impact on liver function and patient management. This study highlights the importance of DAAs in the therapeutic regimen for HCV in the Pakistani population, contributing to better clinical outcomes and healthcare practices.

Biosensor-based multiple cross displacement amplification platform for visual and rapid identification of hepatitis C virus.

Hepatitis C remains a global health problem, especially in poverty-stricken areas. A rapid and sensitive point-of-care (POC) diagnostic tool is critical for the early detection and timely treatment of hepatitis C virus (HCV) infection. Here, for the first time, we reported a novel molecular diagnostic assay, termed reverse transcription multiple cross displacement amplification integrated with a gold-nanoparticle-based lateral flow biosensor (RT-MCDA-AuNPs-LFB), which was developed for rapid, sensitive, specific, and visual identification of HCV. HCV-RT-MCDA induced rapid isothermal amplification through a specific primer set targeting the 5'untranslated region gene from the major HCV genotypes 1b, 2a, 3b, 6a, and 3a that are prevalent in China. The optimal reaction temperature and time for RT-MCDA-AuNPs-LFB were 68°C and 25 min, respectively. The limit of detection of the assay was 10 copies per test, and the specificity was 100% for the experimental strains. The whole detection procedure, including crude nucleic acid isolation (~5 min), RT-MCDA (68°C, 25 min), and visual AuNPs-LFB result confirmation (less than 2 min), was performed within 35 min. The preliminary results indicated that the HCV-RT-MCDA-AuNPs-LFB assay could be a valuable tool for sensitive, specific, visual, cost-saving, and rapid detection of HCV and has potential as a POC diagnostic platform for field screening and early clinical detection of HCV infection.

Rapid, visual, label-based biosensor platform for identification of hepatitis C virus in clinical applications

ObjectivesIn the current study, for the first time, we reported a novel HCV molecular diagnostic approach termed reverse transcription loop-mediated isothermal amplification integrated with a gold nanoparticles-based lateral flow biosensor (RT-LAMP-AuNPs-LFB), which we developed for rapid, sensitive, specific, simple, and visual identification of HCV.MethodsA set of LAMP primer was designed according to 5’untranslated region (5’UTR) gene from the major HCV genotypes 1b, 2a, 3b, 6a, and 3a, which are prevalent in China. The HCV-RT-LAMP-AuNPs-LFB assay conditions, including HCV-RT-LAMP reaction temperature and time were optimized. The sensitivity, specificity, and selectivity of our assay were evaluated in the current study. The feasibility of HCV-RT-LAMP-AuNPs-LFB was confirmed through clinical serum samples from patients with suspected HCV infections.ResultsAn unique set of HCV-RT-LAMP primers were successfully designed targeting on the 5’UTR gene. The optimal detection process, including crude nucleic acid extraction (approximately 5 min), RT-LAMP reaction (67℃, 30 min), and visual interpretation of AuNPs-LFB results (~ 2 min), could be performed within 40 min without specific instruments. The limit of detection was determined to be 20 copies per test. The HCV-RT-LAMP-AuNPs-LFB assay exhibited high specificity and anti-interference.ConclusionsThese preliminary results confirmed that the HCV-RT-LAMP-AuNPs-LFB assay is a sensitive, specific, rapid, visual, and cost-saving assay for identification of HCV. This diagnostic approach has great potential value for point-of-care (POC) diagnostic of HCV, especially in resource-challenged regions.

In Vitro Study of Garcinia dulcis (Roxb.) Kurz Leaves Extract against Hepatitis C Virus

Garcinia dulcis is a plant commonly used in traditional medicine in tropical regions. It has anti-bacterial, anti-inflammatory, anti-tumor, and anti-malaria properties. Despite its potential benefits, studies on its effectiveness as an antiviral are limited. This study investigated the antiviral properties of G. dulcis leaf extract against the JFH-1 strain genotype 2a as a treatment for Hepatitis C Virus (HCV). Huh7it-1 cells infected with the HCV genotype 2a strain JFH-1 were used to determine the antiviral effect of methanol extracts of G. dulcis leaves (GD-LE). GD-LE antiviral activity was investigated using a focus-forming assay for anti-HCV and 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay for cytotoxicity. A time-of-addition study of anti-HCV was also performed to determine the mode of action of GD-LE. The results showed that GD-LE inhibited HCV replication with an IC50 of 17.06 µg/mL without giving any toxicity to the cells. The mode-of-action of GD-LE was found to inhibit HCV replication in the co-addition and post-infection stages. These findings suggest that GD-LE could be a promising candidate for anti-HCV treatment. However, further study regarding GD-LE bioactive compound isolation needs to be done to prepare an effective antiviral.

Genotype Variation of HIV/HCV Co-infections in Karachi, Pakistan

Human Immunodeficiency Virus (HIV) and Hepatitis C Virus (HCV) are among major health issues that affect a large section of the world's population. While HCV affects around 170 million people worldwide, HIV affects 3% of the global population, with 10 million HCV cases documented in Pakistan alone. Co-infection with HIV and HCV results in a variety of genotypic patterns, with significant global heterogeneity in the incidence of spontaneous resolution of hepatitis C and the distribution of HCV genotypes among co-infected individuals. Co-infection is usually transmitted by sexual contact, contaminated blood supplies, and mother-to-child transmission, with high-risk populations like intravenous drug users (IDUs), and men who have sex with men (MSM) having increased vulnerability. This study, conducted in Karachi, Pakistan, aimed to explore the predominant genotypes and viral load of HIV and HCV. The genetic features of the HIV Gag and HCV NS5b genes were examined using genotyping techniques and phylogenetic methodology. The study revealed that out of the 150 individuals examined, 70 were diagnosed with HIV alone, 55 with HCV only, and 25 had both HIV and HCV infections concurrently. Furthermore, genetic analysis demonstrated that HIV-1 subtype A1 was the predominant genotype, with subtype C closely following. In the case of HCV, genotype 3a was the most prevalent in both mono- and co-infected individuals. Notably, individuals with dual infections exhibited limited genotypic variability for each virus. In the case of HIV co-infection, there was an elevation in viral load, while HCV demonstrated lower viremia relative to mono-infection. In conclusion, the study revealed the predominance of HIV-1 subtype A1 and HCV genotype 3a, as well as an elevated level of HIV and a lowered level of HCV in co-infection.

Hepatitis C virus point-of-care microelimination approach in a vulnerable population in the South of Spain.

Since the introduction of direct-acting antivirals, thousands of chronic hepatitis C patients have been successfully treated. However, vulnerable populations have a higher prevalence of hepatitis C virus (HCV) infection and face barriers that impede their access to antivirals. We carried out an HCV microelimination program focused on vulnerable population groups in Malaga. People in drug addiction treatment centers and homeless shelters in Malaga who participated in the program between October 2020 and October 2021 were included. After providing participants with educational information on HCV, a dry drop test (DDT) was used to collect blood for subsequent screening for HCV infection. The participants who were diagnosed with HCV infection were scheduled for comprehensive healthcare assessments, including blood tests, ultrasonography, elastography, and the prescription of antivirals, all conducted in a single hospital visit. Sustained viral response (SVR) was analysed 12 weeks after end of treatment. Of the 417 persons invited to participate, 271 (65%) agreed to participate in the program. These participants were screened for HCV infection and 28 of them were diagnosed with HCV infection (10%). These hepatitis C-infected patients had a mean age of 53 ± 9 years; 86% were males and 93% were or had been drug users. Among 23 patients with HCV infection, HCV genotype 1a predominated (74%). Medical exams showed that 19% (4/21) had advanced fibrosis (F3-4), and 5% (1/21) had portal hypertension. Finally, 23 infected patients received treatment with glecaprevir/pibrentasvir or sofosbuvir/velpatasvir and SVR was confirmed in 22 patients (96%). Drug users and homeless people have a higher prevalence of HCV infection than the general population. The microelimination program with educational activity and screening tools achieved a high participation rate, easy healthcare access, and a high rate of SVR despite the SARS-CoV-2 pandemic.

Hepatitis C virus modified sE2F442NYT as an antigen in candidate vaccine facilitates human immune cell activation.

The rational selection of hepatitis C virus (HCV) vaccine antigen will aid in the prevention of future chronic liver disease burden and associated healthcare costs. We have previously shown that HCV E2 glycoprotein is not highly immunogenic, and the modification of E2 reduced CD81 binding and displayed altered cytokine and protective immune responses in vitro and in a surrogate mouse model. Here, we compared the influence of a parental and a modified sE2F442NYT glycoprotein region from HCV genotype 1a for the activation of peripheral blood mononuclear cell (PBMC)-derived dendritic cells (DCs), CD4+T cells, and B cells. Modified sE2F442NYT, when incubated with DCs, induced a higher number of CD86-positive cells. The sE2F442NYT or parental sE2 encapsulated as mRNA-lipid nanoparticle (sE2F442NYT mRNA-LNP) primed DCs co-cultured with autologous CD4+T cells did not induce CD25 or forkhead box P3 expression. PBMC-derived CD4+T cells treated with sE2F442NYT exhibited enhanced signal transducer and activator of transcription (Stat)1/Stat4 phosphorylation in response to anti-CD3/CD28 stimulation in comparison to parental sE2 treatment and facilitated isotype switching in B cells, leading to the generation of a broader subclass of antibodies. Cells treated with modified sE2F442NYT displayed an increase in activated Stat3 and extracellular signal-regulated kinase (ERK). Likewise, PBMC-derived naïve B cells upon in vitro stimulation with sE2F442NYT induced an increased proliferation, Stat3 and ERK activation, and protein kinase B (Akt) suppression. Thus, the modified sE2F442NYT antigen from HCV facilitates improved DC, CD4+T, and B cell activation compared to parental sE2 to better induce a robust protective immune response, supporting its selection as an HCV candidate vaccine antigen for preclinical and clinical HCV vaccine trials.IMPORTANCEThe nature of an enhanced immune response induced by sE2F442NYT will help in the selection of a broad cross-protective antigen from hepatitis C virus genotypes, and the inclusion of relatively conserved sE1 with sE2F442NYT may further strengthen the efficacy of the candidate vaccine in evaluating it for human use.

Community-Based Point-of-Diagnosis Hepatitis C Treatment for Marginalized Populations

Disparities persist in testing and treatment for hepatitis C virus (HCV), leaving socially marginalized populations less likely to benefit from curative treatment. Linkage services are often insufficient to overcome barriers to navigating the medical system and contextual factors. To determine the feasibility, acceptability, and safety of HCV treatment at the point of HCV infection diagnosis disclosure in a nonclinical community setting. In this single-arm nonrandomized controlled trial conducted between July 1, 2020, and October 31, 2021, street-outreach recruitment targeted people experiencing homelessness and injecting drugs in an urban US community who were eligible for simplified HCV treatment. Study procedures were designed to reflect the community environment and services needed to provide HCV testing, disclosure, and treatment in a nonclinical site. The test-and-treat No One Waits (NOW) model of care provided a 2-week starter pack of 400 mg of sofosbuvir and 100 mg of velpatasvir at time of HCV RNA results disclosure. Participants were transitioned to insurance-provided sofosbuvir-velpatasvir when feasible to complete a 12-week treatment course. The primary end point was sustained virologic response at posttreatment week 12 or later (SVR12). Acceptability end points were treatment initiation and completion. Safety end points were treatment discontinuation because of a late exclusion criterion and adverse events. Of the 492 people (median [IQR] age, 48 [37-58] years; 62 [71%] male) who underwent anti-HCV testing, 246 (50%) tested anti-HCV positive, and 111 (23%) tested HCV RNA positive and were eligible for simplified HCV treatment. Eighty-nine of the 111 eligible participants (80%) returned for confirmatory RNA results, and 87 (98%) accepted and initiated HCV treatment. Seventy (80%) were currently injecting drugs, 83 (97%) had an income below the poverty line, and 53 (61%) were currently unsheltered. Most had HCV genotype 1a (45 [52%]) or 3 (20 [23%]). Sixty-nine (79%) completed 12 weeks of sofosbuvir-velpatasvir treatment, 2 stopped treatment because of low adherence, and 16 were lost to follow-up. Of the 66 participants who completed treatment and had a successful blood draw, 61 (92%) had undetectable HCV RNA at treatment completion. Of the 87 treated patients, 58 achieved SVR12, leading to a treatment response of 67% (95% CI, 56%-76%) among the intention-to-treat group and 84% (95% CI, 73%-92%) among the per-protocol group. There were no adverse events, late exclusions, or deaths. In this nonrandomized controlled trial of HCV treatment at the point of diagnosis, the NOW model of care reduced steps between HCV testing and treatment initiation and resulted in high levels of treatment initiation, completion, and cure. The NOW model of care can expand the current HCV test-and-treat toolkit by reaching a broader population of marginalized communities and expediting curative therapy. ClinicalTrials.gov Identifier: NCT03987503.

Antibody designing against IIIabc junction (JIIIabc) of HCV IRES through affinity maturation; RNA-Antibody docking and interaction analysis.

Hepatitis C virus is a single-stranded RNA based virus which can cause chronic HCV and hepatocellular carcinoma. HCV genotype 3a has relatively higher rate of fibrosis progression, prevalence of steatosis and incidence of HCC. Despite HCVs variation in genomic sequence, the 5' untranslated region containing internal ribosome entry site (IRES) is highly conserved among all genotypes. It is responsible for translation and initiation of the viral protein. In present study, IRES was targeted by designing variants of reported antigen binding fragment (Fab) through affinity maturation approach. Affinity maturation strategy allowed the rational antibody designing with better biophysical properties and antibody-antigen binding interactions. Complementarity determining regions of reported Fab (wild type) were assessed and docked with IRES. Best generated model of Fab was selected and subjected to alanine scanning Three sets of insilico mutations for variants (V) designing were selected; single (1-71), double (a-j) and triple (I-X). Redocking of IRES-Fab variants consequently enabled the discovery of three variants exhibiting better docking score as compared to the wild type Fab. V1, V39 and V4 exhibited docking scores of -446.51, -446.52 and-446.29 kcal/mol respectively which is better as compared to the wild type Fab that exhibited the docking score of -351.23 kcal/mol. Variants exhibiting better docking score were screened for aggregation propensity by assessing the aggregation prone regions in Fab structure. Total A3D scores of wild type Fab, V1, V4 and V39 were predicted as -315.325, -312.727, -316.967 and -317.545 respectively. It is manifested that solubility of V4 and V39 is comparable to wild type Fab. In future, development and invitro assessment of these promising Fab HCV3 variants is aimed.

An amino acid substitution in HCV core antigen limits its use as a reliable measure of HCV infection compared with HCV RNA.

Hepatitis C virus (HCV) is a viral pathogen that causes chronic hepatitis, which can lead to cirrhosis and hepatocellular carcinoma. Detection of HCV RNA is the standard method used to diagnose the disease and monitor antiviral treatment. A quantification assay for the HCV core antigen (HCVcAg) has been proposed as a simplified alternative to the HCV RNA test for predicting active HCV infection, with the aim of achieving the global goal of eliminating hepatitis. The objective of this study was to determine the correlation between HCV RNA and HCVcAg, as well as the impact of amino acid sequence heterogeneity on HCVcAg quantification. Our findings demonstrated a strong positive correlation between HCV RNA and HCVcAg across all HCV genotypes (1a, 1b, 3a, and 6), with correlation coefficients ranging from 0.88 to 0.96 (p < 0.001). However, in some cases, samples with genotypes 3a and 6 exhibited lower HCVcAg levels than expected based on the corresponding HCV RNA values. Upon the core amino acid sequence alignment, it was observed that samples exhibiting low core antigen levels had an amino acid substitution at position 49, where threonine was replaced by either alanine or valine. Core mutation at this position may correlate with one of the epitope regions recognized by anti-HCV monoclonal antibodies. The present findings suggest that the utilization of HCVcAg as a standalone marker for HCV RNA might not provide adequate sensitivity for the detection of HCV infection, especially in cases where there are variations in the amino acid sequence of the core region and a low viral load of HCV RNA.

Retreatment of patients with chronic hepatitis C, subtype 3a, and cirrhosis, who previously failed a regimen containing NS5A inhibitors with sofosbuvir/velpatasvir plus ribavirin for 24 weeks

Background & Aims The use of direct acting antiviral agents (DAAs) in patients with chronic HCV genotype (GT) 3a infection results in sustained virologic response (SVR) rates of 93–98%, but 5–8% of patients experience virologic failure. Methods. We observed 48 patients infected with HCV subtype 3a who failed previous treatment with DAAs, including 43 subjects (89.6%) with liver cirrhosis. Thirty-seven (77%) subjects previously received NS5A inhibitors of the first generation (daclatasvir) and 11 subjects (23%) – of the second generation (velpatasvir). All patients received retreatment with sofosbuvir (SOF)/ velpatasvir (VEL) and ribavirin (RBV) for 24 weeks. We compared SVR12 rates depending on fibrosis stage, presence of NS5A mutation (L31M or A30K and Y93H), and on the generation of previously used NS5A inhibitors. Results. Observed SVR12 rate were: 83,3% (40/48 patients) overall; 100% in patients without cirrhosis (n=5) vs 81,4% (n=35) in those with cirrhosis (n=43) (P=0,01); 86,7% (n=13) with single L31M or A30K(n=15) vs 77,8% (n=21) with Y93H mutation (n=27) (P=0,46), 86,5% (n=32) in patients who previously failed first generation (n=37) vs 72,7% (n=8) in those who failed second generation NS5A inhibitors (n=11) (P=0,35). Conclusions. Retreatment with SOF/VEL+RBV was highly effective and safe in patients with chronic HCV GT3a infection, including those with liver cirrhosis, who previously failed DAA containing NS5A inhibitors. Presence of NS5A RASs L31M, A30K, and Y93H at the baseline, as well as the generation of previously used NS5A inhibitors did not impact SVR12 rates.

ANGPTL4 is a potential driver of HCV-induced peripheral insulin resistance

Chronic hepatitis C (CHC) is associated with the development of metabolic disorders, including both hepatic and extra-hepatic insulin resistance (IR). Here, we aimed at identifying liver-derived factor(s) potentially inducing peripheral IR and uncovering the mechanisms whereby HCV can regulate the action of these factors. We found ANGPTL4 (Angiopoietin Like 4) mRNA expression levels to positively correlate with HCV RNA (r = 0.46, p < 0.03) and HOMA-IR score (r = 0.51, p = 0.01) in liver biopsies of lean CHC patients. Moreover, we observed an upregulation of ANGPTL4 expression in two models recapitulating HCV-induced peripheral IR, i.e. mice expressing core protein of HCV genotype 3a (HCV-3a core) in hepatocytes and hepatoma cells transduced with HCV-3a core. Treatment of differentiated myocytes with recombinant ANGPTL4 reduced insulin-induced Akt-Ser473 phosphorylation. In contrast, conditioned medium from ANGPTL4-KO hepatoma cells prevented muscle cells from HCV-3a core induced IR. Treatment of HCV-3a core expressing HepG2 cells with PPARγ antagonist resulted in a decrease of HCV-core induced ANGPTL4 upregulation. Together, our data identified ANGPTL4 as a potential driver of HCV-induced IR and may provide working hypotheses aimed at understanding the pathogenesis of IR in the setting of other chronic liver disorders.

Identification of novel neutralizing determinants for protection against HCV.

HCV evasion of neutralizing antibodies (nAb) results in viral persistence and poses challenges to the development of an urgently needed vaccine. N-linked glycosylation of viral envelope proteins is a key mechanism for such evasion. To facilitate rational vaccine design, we aimed to identify determinants of protection of conserved neutralizing epitopes. Using a reverse evolutionary approach, we passaged genotype 1a, 1b, 2a, 3a, and 4a HCV with envelope proteins (E1 and E2) derived from chronically infected patients without selective pressure by nAb in cell culture. Compared with the original viruses, HCV recombinants, engineered to harbor substitutions identified in polyclonal cell culture-passaged viruses, showed highly increased fitness and exposure of conserved neutralizing epitopes in antigenic regions 3 and 4, associated with protection from chronic infection. Further reverse genetic studies of acquired E1/E2 substitutions identified positions 418 and 532 in the N1 and N6 glycosylation motifs, localizing to adjacent E2 areas, as key regulators of changes of the E1/E2 conformational state, which governed viral sensitivity to nAb. These effects were independent of predicted glycan occupancy. We show how N-linked glycosylation motifs can trigger dramatic changes in HCV sensitivity to nAb, independent of glycan occupancy. These findings aid in the understanding of HCV nAb evasion and rational vaccine design, as they can be exploited to stabilize the structurally flexible envelope proteins in an open conformation, exposing important neutralizing epitopes. Finally, this work resulted in a panel of highly fit cell culture infectious HCV recombinants.

The effect of genotype variation and M423 resistance mutations to the binding of phosphonomidate-based inhibitor IDX17119 with the thumb-II domain of Hepatitis C virus RdRp: an integrated molecular dynamics and binding free energy study

ABSTRACT The IDX17119 is a phosphonomidate-based pan-genotypic non-nucleoside inhibitor of Hepatitis C Virus (HCV) NS5B RdRp thumb-II domain. IDX17119 exhibits significant antiviral activity against HCV genotype (GT) 1a, 2a, 3a and 4a. The molecular docking analysis was performed to understand the binding and intermolecular interactions of the IDX17119 molecule at the thumb-II domain of 1a, 2a, 3a and 4a GT NS5B RdRps. The molecular dynamics simulation has been performed to determine the stability of the ligand–protein complexes. We found GT 1a complex is relatively stable compared with other drug-receptor complexes. The binding free energy calculations and free energy decomposition analysis were carried out for all the complexes, the result revealed that the increase in the unfavourable polar contribution affects the binding of IDX17119 with GT 2a NS5B RdRp compared with all other complexes. In addition to this, the effect of mutation at M423 site (M423T/V) alters the conformation and activity of the IDX17119 molecule.

S3264 A Hepatitis C (HCV) Infection Treatment Dilemma

Introduction: HIV/HCV coinfection increases liver-related morbidity and mortality. This special population should be prioritized for treatment. Currently available direct-acting antivirals (DAAs) are safe and effective, but there are many drug interactions (DIs) to consider. Carbamazepine (CBZ) is contraindicated with all available DAAs. Patients that require treatment for HCV but cannot stop CBZ do not have a clear treatment option. Patients may be transitioned to newer antiepileptics that do not have the same contraindications, but some patients are unwilling or unable to change medications. Case Description/Methods: Patient is a 59-year-old man with well-controlled HIV on HAART, well-controlled trigeminal neuralgia on CBZ, anemia, and non-cirrhotic (FibroScan 12 kPa), treatment naïve, chronic HCV genotype 1a. Due to DIs between DAAs and CBZ, multiple attempts were made to discontinue CBZ but were unsuccessful. Neurosurgery offered surgical gamma knife management, but up to 40% of patients still require CBZ post-procedure. An initial plan for daclatasvir (DAC)-sofosbuvir (SOF)-ribavirin (RBV) was proposed, but DAC is no longer available in the US. Patient was followed conservatively but developed thrombocytopenia and progression of fibrosis (FibroScan 14.7kPa). Given worsening liver condition, shared decision-making was performed, and patient completed 16 weeks of Glecaprevir (GLE)/pibrentasvir (PIB) + SOF 400mg with 4 weeks of ezetimibe 10mg stopping when the viral load was undetectable. Patient was instructed to start the ezetimibe with the GLE/PIB + SOF but was hesitant to take it due to adverse reaction to statins in the past. At 4 weeks of treatment, HCV viral load was still detectable. Patient was re-educated on the purpose of the ezetimibe and reassured it was not a statin. He took it from week 4-8 of treatment. At week 8, HCV viral load was undetectable. Patient achieved SVR 12 and showed improvement of his FibroScan score to 9.6 kPa. Discussion: GLE/PIB is pangenotypic, has a high barrier to resistance, and has been proven safe and effective in combination with SOF + RBV in MAGELLAN 3 for 16 weeks duration. Patient has history of anemia, making RBV undesirable. Ezetimibe blocks the NPC1L receptor which potentially inhibits HCV entry into the hepatocyte. HCV relies on cell-to-cell transmission, so we chose to add ezetimibe 10mg daily until HCV not detected. There is a need for larger studies to determine the applicability of this case study to other patients.

Persistent Transmission of HCV among Men Who Have Sex with Men despite Widespread Screening and Treatment with Direct-Acting Antivirals.

Background: In the Netherlands, unrestricted access to direct-acting antivirals (DAAs) halved the incidence of acute hepatitis C virus (HCV) infections among HIV-infected men who have sex with men (MSM). To develop strategies that can further reduce the spread of HCV, it is important to understand the transmission dynamics of HCV. We used phylogenetic analysis of a dense sample of MSM to provide insight into the impact of unrestricted access to DAAs on HCV transmission in the Netherlands and in Belgium. Methods: We included 89 MSM that were recently infected with HCV genotype 1a in ten Dutch and one Belgian HIV treatment centers. Sequences were generated using next gene sequencing and Sanger sequencing. Maximum likelihood phylogenetic analysis (general time reversible model) was performed on concatenated NS5A and NS5B sequences and a reference set of 389 highly similar control sequences selected from GenBank. A cluster was based on a minimum bootstrap support of 90% and a 3% genetic distance threshold. Results: We found that 78 (88%) of individuals were part of seven major clusters. All clusters included individuals from across the study region, however, different cities were part of different clusters. In three clusters, HIV-negative MSM clustered with sequences from HIV-positive MSM. All clusters that were observed before the introduction of DAAs persisted after unrestricted access to DAAs became available. Conclusion: Recently acquired HCV infections among MSM in the Netherlands and Belgium are strongly clustered and therefore highly suitable for targeted prevention strategies, such as contact tracing and partner notification. Importantly, despite an HCV incidence reduction after high DAA uptake and continuously monitoring, HCV transmission persisted in the same clusters.

High real-world effectiveness of 12-week elbasvir/grazoprevir without resistance testing in the treatment of patients with HCV genotype 1a infection in Norway

Background and aims The recommended treatment duration of hepatitis C virus (HCV) genotype 1a (GT1a) infection with elbasvir/grazoprevir (EBR/GZR) in the presence of a high baseline viral load and resistance associated substitutions (RAS) is 16 weeks with ribavirin added. The objective of this study was to evaluate the real-world effectiveness of 12 weeks of EBR/GZR without ribavirin and regardless of baseline viral load and RAS testing. Method This retrospective, observational cohort study was performed at five Norwegian hospitals that did not systematically utilize RAS testing. All adult patients with chronic HCV GT1a and compensated liver disease who had received 12 weeks of EBR/GZR without ribavirin and baseline RAS testing, were included. The primary endpoint was sustained virologic response at week 12 (SVR12), or if not available, at week 4 (SVR4). Results We included 433 patients and attained SVR data on 388. The mean age was 45.7 years (22–73 years). 67.2% were male. HIV co-infection was present in 3.8% (16/424) and cirrhosis in 4% (17/424). The viral load was >800 000 IU/mL in 55.0% (235/427) of patients. Overall SVR was achieved in 97.2% (377/388). SVR was achieved in 98.3% (169/172) of those with viral load ≤800 000 IU/mL and in 96.2% (202/210) of those with viral load >800 000 IU/mL. Conclusion We observed high SVR rates among patients with HCV GT1a infection treated with EBR/GZR for 12 weeks without ribavirin, with no regard to baseline viral load and no RAS testing.

Partial nonstructural 3 region analysis of hepatitis C virus genotype 3a.

The hepatitis C virus (HCV) is a major cause of illness around the world. HCV genotype 3a is the most prevalent genotype in Thailand. Direct-acting antiviral (DAA) drugs are available for treatment, and these drugs target the NS3, NS5A, and NS5b proteins of HCV. However, HCV variants that are resistant to NS3 protease inhibitors have been found during treatment. This resistance can be naturally occurring or in response to treatment. The purpose of this study is to analyze the codon positions of the main mutation of the partial NS3 gene region of HCV genotype 3a. In order to detect mutations and confirm the genotype of HCV genotype 3a, the nucleotide sequencing and amino acid portion of NS3 were analyzed. Twenty-six samples were successfully sequenced and clustered within two sub-clades defined as 3a-1 and 3a-2. Through amino acid mutation analysis, the variations were detected at codon positions 122 (3.8%), 132 (84.6%), 168 (100%), 170 (92.3%), 174 (100%), and 175 (100%). In conclusion, mutations at positions 168, 170, 174, and 175 of the NS3 region are common within the HCV genotype 3a. This information should be useful in the development of effective anti-viral drugs that can successfully treat HCV infection.

Inactivated genotype 1a, 2a and 3a HCV vaccine candidates induced broadly neutralising antibodies in mice

ObjectiveA prophylactic vaccine is needed to control the HCV epidemic, with genotypes 1–3 causing >80% of worldwide infections. Vaccine development is hampered by HCV heterogeneity, viral escape including protection of...