New hepatitis C therapies: the toolbox, strategies, and challenges

Rationale for Hepatitis C Virus Treatment During Hematopoietic Stem Cell Transplant in the Era of Novel Direct-Acting Antivirals

BACKGROUND AND AIMS

Untreated hepatitis C (HCV) infection in patients undergoing hematopoietic stem cell transplantation (HSCT) can lead to worse outcomes. Traditionally, HSCT patients infected with HCV would wait until after immune reconstitution to receive HCV therapy, as the oncologic urgency of transplant would not allow time for a full preceding treatment course of HCV therapy. However, in the era of newer direct-acting antivirals (DAAs), we propose that concomitant treatment of HCV while undergoing HSCT is safe and feasible, while keeping in mind potential drug-drug interactions.

METHODS

A literature review was performed to summarize the available data on the impact of HCV on patients undergoing HSCT. Drug-drug interactions for DAA's and pertinent HSCT drugs were evaluated using Lexicomp online® and http://hep-druginteractions.org .

RESULTS

During HSCT, HCV appears to be a conditional risk factor for sinusoidal obstruction syndrome and a potential risk factor for graft versus host disease, both of which are associated with increased mortality. HCV reactivation and exacerbation may impact the use of chemotherapeutics, but available studies haven't shown impact specifically on HSCT. Limited case reports exist but demonstrate safe and effective use DAAs during HSCT. These, along with a drug-drug interaction review demonstrate agents such as sofosbuvir/velpatasvir and glecaprevir/pibrentasvir are promising DAAs for use in HSCT.

CONCLUSION

HCV infection may worsen outcomes for patients undergoing HSCT. Concomitant treatment of HCV during HSCT using newer DAAs appears feasible and may improve patient morbidity and mortality, however large-scale studies are needed to further support this practice.

Effects of sustained viral response on lipid in Hepatitis C: a systematic review and meta-analysis

BACKGROUND

Direct-acting Antiviral Agents (DAAs) influence serum lipids of patients with Hepatitis C virus (HCV). This paper presents an analysis of the relevant literature to investigate the effects of DAAs in treating hepatitis C to achieve a sustained viral response (SVR) on lipid parameters.

METHODS

PubMed,Web of science, Embase and Central databases were searched, with a deadline of September 2023. Studies on the effects of sustained viral response on lipid parameters after DAAs treatment for hepatitis C were selected. The required information was extracted from the included studies, and then the Stata 12.0 was used to analyze the data quantitatively.

RESULTS

Of 32 studies, the results showed that total cholesterol (TC) levels increased from the end of treatment (WMD = 20.144, 95%CI = 3.404, 36.884,P = 0.018) to one year after treatment (WMD = 24.900, 95%CI = 13.669, 36.131, P < 0.001). From the end of treatment (WMD = 17.728, 95%CI = 4.375, 31.082, P = 0.009) to one year after treatment (WMD = 18.528, 95%CI = 7.622, 29.433, P < 0.001), the levels of low-density lipoprotein (LDL) were also increased. High-density lipoprotein (HDL) levels were elevated from 4 weeks after treatment (WMD = 6.665, 95%CI = 3.906, 9.424, P < 0.001) to 24 weeks after treatment (WMD = 3.159,95% CI = 0.176, 6.142, P = 0.038). Triglyceride (TG) levels showed no significant change after the treatment.

CONCLUSIONS

Hepatitis C patients who achieved SVR on DAAs showed the increase of lipid levels and the improvement of hepatic inflammation indicators AST and ALT. This may provide evidence-based medical evidence for the follow-up and monitoring of blood lipids and hyperlipidemia treatment.

REGISTRATION

PROSPERO CRD42020180793.

Structure-based virtual screening of natural compounds as inhibitors of HCV using molecular docking and molecular dynamics simulation studies

The hepatitis C virus (HCV), which causes hepatitis C, is a viral infection that damages the liver and causes inflammation in the liver. New potentially effective antiviral drugs are required for its treatment owing to various issues associated with the existing medications, including moderate to severe adverse effects, higher costs, and the emergence of drug-resistant strains. The objective of the current study was to utilize computational techniques to assess the anti-HCV efficacy of certain phytochemicals against tetraspanin (CD81) and claudin 1 (CLDN1) entry proteins. A 200-nanosecond molecular dynamics (MD) simulation was employed to examine the stability of the lead-protein complexes. Free binding energy and molecular docking calculations were conducted utilizing MM/GBSA method, and the selectivity of hit compounds for CD81 and CLDN1 was determined. Five significant CD81 and CLDN1 inhibitors were identified: Petasiphenone, Silibinin, Tanshinone IIA, Taxifolin, and Topaquinone. The MM/GBSA analysis of the compounds revealed high free binding energies. All the identified compounds were stable within the CD81 and CLDN1 binding pockets. This study indicated the promising inhibitory potential of the identified compounds against CD81 and CLDN1 receptors and might develop into potential viral entry inhibitors. However, to validate the chemotherapeutic capabilities of the discovered leads extensive preclinical research is required.Communicated by Ramaswamy H. Sarma.

Construction and characterization of a new hepatitis C virus genotype 6a subgenomic replicon that is prone to render the sofosbuvir resistance

Hepatitis C virus (HCV) infection remains a challenge to human public health despite the development of highly effective direct-acting antivirals (DAAs). Sofosbuvir (SOF), a key component in most DAA-based anti-HCV cocktail regimens, is a potent viral RNA polymerase (NS5B) inhibitor with a high barrier to drug resistance. The serine-to-threonine mutation at NS5B 282 (S282T) confers the SOF resistance, but severely impairs viral replication in most HCV genotypes (GTs) and cannot be stably maintained after the termination of the SOF-based therapies. In this study, we first developed a new HCV GT-6a subgenomic replicon PR58D6. Next, we selected SOF-resistant PR58D6 variants by culturing the replicon cells in the presence of SOF. Interestingly, unlike many other HCV replicons which require additional mutations to compensate for the S282T-inducing fitness loss, S282T alone in PR58D6 is genetically stable and confers the SOF resistance without significantly impairing viral replication. Furthermore, we showed that amino acid residue at NS5B 74 (R74) and 556 (D556) which are conserved in GT 6a HCV contribute to efficient replication of PR58D6 containing S282T. Finally, we showed that the G556D mutation in NS5B could rescue the replication deficiency of the S282T in JFH1, a GT-2a replicon. In conclusion, we showed that a novel GT-6a HCV replicon may easily render SOF resistance, which may call for attention to potential drug resistance during DAA therapies of HCV GT-6a patients.

Evaluation of the effect of direct-acting antiviral agents on melatonin level and lipid peroxidation in chronic hepatitis C patients

Background: Oxidative stress and its end products, such as malondialdehyde (MDA) play a leading role in the pathogenesis of hepatitis C. Melatonin is a hormone that helps regulate circadian rhythms, which likely play a role in infectious diseases in terms of susceptibility, clinical expression, and outcome. Objective: The present study was conducted to assess serum malondialdehyde and melatonin levels in patients with chronic hepatitis C infection before and after the intake of direct-acting antivirals. Method: Forty hepatitis C patients were the subjects of this study. While ten healthy volunteers who matched in age and socioeconomic status served as the control subjects. Malondialdehyde and melatonin were assayed in the serum of the three groups, and the results were statistically analyzed. Results: Hepatitis C patients had significantly higher malondialdehyde (p < 0.001) but significantly lower melatonin (p < 0.001) as compared to the healthy controls. After 12 weeks of treatment with direct-acting antivirals, the malondialdehyde level decreased significantly (p < 0.001) and the melatonin level increased significantly (p < 0.001). A significant negative correlation between malondialdehyde and melatonin was observed. Conclusion: The present findings suggest that treatment of hepatitis C patients with Direct-acting antivirals improves liver function parameters and antioxidant profiles.

Usefulness of aMAP Risk Score for Predicting Recurrence after Curative Treatment for Hepatocellular Carcinoma within Milan Criteria

INTRODUCTION

The aMAP score is a prediction model for hepatocellular carcinoma (HCC) risk in chronic hepatitis patients. This study was conducted to elucidate the utility of this model for predicting initial recurrence of HCC in patients within the Milan criteria after undergoing curative treatment.

METHODS

Patients with naïve HCC within the Milan criteria (n = 1,020) and treated from January 2000 to August 2022 were enrolled. The cohort was divided into two groups according to the aMAP score (high ≥60, low <60) and then compared for recurrence-free survival (RFS) and overall survival (OS).

RESULTS

Comparisons between the high and low groups showed that etiology (HBV:HCV:HBV+HCV:NBNC = 41:79:2:37 vs. 65:589:11:196, p < 0.001), AST (36 vs. 46 IU/L, p < 0.001), and multiple HCC occurrence (15% vs. 22%, p = 0.026) were significantly different. Additionally, median RFS (59.8 vs. 30.9 months; p < 0.001) and median OS (154.1 vs. 83.4 months, p < 0.01) were greater in the low group. As for patients with HCC due to chronic viral hepatitis, there was a significant difference in median RFS between the groups (59.8 vs. 30.6 months, p < 0.001), especially for HCV-positive patients (53.1 vs. 27.2 months, p = 0.002). In patients with HCC due to a nonviral cause, the difference in median RFS between the low (70.9 months) and high (32.0 months) groups was not significant.

DISCUSSION

Findings of this retrospective study indicate a significant association of elevated aMAP with worse RFS in patients with HCC caused by chronic viral hepatitis, especially those with HCV. The aMAP score is considered useful to predict not only HCC-carcinogenesis risk but also risk of recurrence following curative treatment.

Real-world experience for the outcomes and costs of treating hepatitis C patients: Results from the German Hepatitis C-Registry (DHC-R)

BACKGROUND & AIMS

With long-term consequences like the development of liver cirrhosis and hepatocellular carcinoma, chronic hepatitis C virus (HCV) infection is associated with a significant health burden. Information on HCV treatment outcomes and costs in routine care is still rare, especially for subgroups. The aim of this study was to analyse the treatment outcomes and costs of subgroups in routine care and to compare them over time with previous analyses.

METHODS

Data were derived from a noninterventional study including a subset of 10298 patients receiving DAAs with genotypes 1 and 3. Sociodemographic, clinical parameters and costs were collected using a web-based data recording system. The total sample was subdivided according to treatment regimen, cirrhosis status as well as present HIV infection and opioid substitution treatment (OST).

RESULTS

95% of all patients achieved SVR. Currently used DAA showed higher SVR-rates and less adverse events (AE) compared to former treatments. Concerning subgroups, cirrhotic patients, HIV-coinfected patients and OST patients showed lower but still high SVR-rates. In comparison, cirrhotic had considerably longer treatment duration and more frequent (serious) AE. Overall, average treatment costs were €48470 and costs per SVR were €51129; for currently used DAAs costs amounted to €30330 and costs per SVR to €31692. After the end of treatment, physical health is similar to the general population in all patients except cirrhotic. Mental health remains far behind in all subgroups, even for currently used DAA.

CONCLUSIONS

Over time, some relevant factors developed positively (SVR-rates, costs, treatment duration, adverse events, health-related quality of life (HRQoL)). Further research on HRQoL, especially on mental health, is necessary to evaluate the differences between subgroups and HRQoL over time and to identify influencing factors.

Mechanisms and Consequences of Genetic Variation in Hepatitis C Virus (HCV)

Chronic infection with hepatitis C virus (HCV) is an important contributor to the global incidence of liver diseases, including liver cirrhosis and hepatocellular carcinoma. Although common for single-stranded RNA viruses, HCV displays a remarkable high level of genetic diversity, produced primarily by the error-prone viral polymerase and host immune pressure. The high genetic heterogeneity of HCV has led to the evolution of several distinct genotypes and subtypes, with important consequences for pathogenesis, and clinical outcomes. Genetic variability constitutes an evasion mechanism against immune suppression, allowing the virus to evolve epitope escape mutants that avoid immune recognition. Thus, heterogeneity and variability of the HCV genome represent a great hindrance for the development of vaccines against HCV. In addition, the high genetic plasticity of HCV allows the virus to rapidly develop antiviral resistance mutations, leading to treatment failure and potentially representing a major hindrance for the cure of chronic HCV patients. In this chapter, we will present the central role that genetic diversity has in the viral life cycle and epidemiology of HCV. Incorporation errors and recombination, both the result of HCV polymerase activity, represent the main mechanisms of HCV evolution. The molecular details of both mechanisms have been only partially clarified and will be presented in the following sections. Finally, we will discuss the major consequences of HCV genetic diversity, namely its capacity to rapidly evolve antiviral and immunological escape variants that represent an important limitation for clearance of acute HCV, for treatment of chronic hepatitis C and for broadly protective vaccines.

Circulating microRNAs as predictors of response to sofosbuvir + daclatasvir + ribavirin in in HCV genotype-4 Egyptian patients

BACKGROUND

MicroRNAs (miRNAs) play an important role in various diseases, including HCV infection, the aim of the current study was to evaluate the potential use of serum miRNAs as biomarkers for diagnosis, prognosis, and prediction of responses to direct acting antivirals (sofosbuvir + daclatasvir + ribavirin) in HCV-4 patients.

METHODS

The serum expression profiles of four liver-associated miRNAs (miRNA-122, 155, 196 and 29) were assessed in 160 HCV-4 patients and 50 healthy controls using real-time PCR prior to therapy.

RESULTS

miR-122 and miR-155 showed upregulation in HCV-4 patients compared to healthy controls while miR-196 and miR-29 showed downregulation in HCV-4 patients. ROC curve analyses revealed that the four-studied miRNAs could be valuable biomarkers for predicting response to DAAs with AUC 0.973 for miR-122, 0.878 for miR-155, 0.808 for miR-29 and 0.874 for miR-196 respectively. Univariate logistic regression analysis revealed that miR-196 level is positive predictor for SVR, whereas miR-122,155 levels are negative predictors of response. Multivariate logistic regression analysis revealed that miR-196 is the most significant in predicting response to treatment (p value = 0.011).

CONCLUSION

To the best of our knowledge, the current study provided the first clinical evidence of the potential use of circulating miRNAs (miR; 122, 155, 196 and 29) as biomarkers of CHC in HCV-4 patients receiving the new DAA regimen (SOF/DAV + RIB), which is a strong motivator for further studies.

Characterisation of a Hepatitis C Virus Subtype 2a Cluster in Scottish PWID with a Suboptimal Response to Glecaprevir/Pibrentasvir Treatment

Direct-acting antivirals (DAAs) have revolutionised the treatment of Hepatitis C virus (HCV), allowing the World Health Organisation (WHO) to set a target of eliminating HCV by 2030. In this study we aimed to investigate glecaprevir and pibrentasvir (GP) treatment outcomes in a cohort of patients with genotype 2a infection.

METHODS

Clinical data and plasma samples were collected in NHS Greater Glasgow & Clyde. Next generation whole genome sequencing and replicon assays were carried out at the MRC-University of Glasgow Centre for Virus Research.

RESULTS

132 cases infected with genotype 2a HCV were identified. The SVR rate for this group was 91% (112/123) following treatment with GP. An NS5A polymorphism, L31M, was detected in all cases of g2a infection, and L31M+R353K in individuals that failed treatment. The results showed that R353K was present in 90% of individuals in the Glasgow genotype 2a phylogenetic cluster but in less than 5% of all HCV subtype 2a published sequences. In vitro efficacy of pibrentasvir against sub-genomic replicon constructs containing these mutations showed a 2-fold increase in IC₅₀ compared to wildtype.

CONCLUSION

This study describes a cluster of HCV genotype 2a infection associated with a lower-than-expected SVR rate following GP treatment in association with the NS5A mutations L31M+R353K.

Targeting non-structural proteins of Hepatitis C virus for predicting repurposed drugs using QSAR and machine learning approaches

Hepatitis C virus (HCV) infection causes viral hepatitis leading to hepatocellular carcinoma. Despite the clinical use of direct-acting antivirals (DAAs) still there is treatment failure in 5–10% cases. Therefore, it is crucial to develop new antivirals against HCV. In this endeavor, we developed the “Anti-HCV” platform using machine learning and quantitative structure–activity relationship (QSAR) approaches to predict repurposed drugs targeting HCV non-structural (NS) proteins. We retrieved experimentally validated small molecules from the ChEMBL database with bioactivity (IC₅₀/EC₅₀) against HCV NS3 (454), NS3/4A (495), NS5A (494) and NS5B (1671) proteins. These unique compounds were divided into training/testing and independent validation datasets. Relevant molecular descriptors and fingerprints were selected using a recursive feature elimination algorithm. Different machine learning techniques viz. support vector machine, k-nearest neighbour, artificial neural network, and random forest were used to develop the predictive models. We achieved Pearson’s correlation coefficients from 0.80 to 0.92 during 10-fold cross validation and similar performance on independent datasets using the best developed models. The robustness and reliability of developed predictive models were also supported by applicability domain, chemical diversity and decoy datasets analyses. The “Anti-HCV” predictive models were used to identify potential repurposing drugs. Representative candidates were further validated by molecular docking which displayed high binding affinities. Hence, this study identified promising repurposed drugs viz. naftifine, butalbital (NS3), vinorelbine, epicriptine (NS3/4A), pipecuronium, trimethaphan (NS5A), olodaterol and vemurafenib (NS5B) etc. targeting HCV NS proteins. These potential repurposed drugs may prove useful in antiviral drug development against HCV.

Epidemiology, risk factors, and pathogenesis associated with a superbug: A comprehensive literature review on hepatitis C virus infection

Viral hepatitis is a major public health concern. It is associated with life threatening conditions including liver cirrhosis and hepatocellular carcinoma. Hepatitis C virus infects around 71 million people annually, resultantly 700,000 deaths worldwide. Extrahepatic associated chronic hepatitis C virus accounts for one fourth of total healthcare load. This review included a total of 150 studies that revealed almost 19 million people are infected with hepatitis C virus and 240,000 new cases are being reported each year. This trend is continually rising in developing countries like Pakistan where intravenous drug abuse, street barbers, unsafe blood transfusions, use of unsterilized surgical instruments and recycled syringes plays a major role in virus transmission. Almost 123–180 million people are found to be hepatitis C virus infected or carrier that accounts for 2%–3% of world’s population. The general symptoms of hepatitis C virus infection include fatigue, jaundice, dark urine, anorexia, fever malaise, nausea and constipation varying on severity and chronicity of infection. More than 90% of hepatitis C virus infected patients are treated with direct-acting antiviral agents that prevent progression of liver disease, decreasing the elevation of hepatocellular carcinoma. Standardizing the healthcare techniques, minimizing the street practices, and screening for viral hepatitis on mass levels for early diagnosis and prompt treatment may help in decreasing the burden on already fragmented healthcare system. However, more advanced studies on larger populations focusing on mode of transmission and treatment protocols are warranted to understand and minimize the overall infection and death stigma among masses.

Analysis of the albumin‐bilirubin score as an indicator of improved liver function among hepatitis C virus patients with sustained viral response after direct‐acting antiviral therapy

Background and Aim

To investigate the performance of the albumin‐bilirubin (ALBI) score as an indicator of improved hepatic function using a cohort of hepatitis C virus (HCV) patients with sustained viral response (SVR) after direct‐acting antiviral therapy (DAA).

Methods

HCV patients who achieved SVR after DAAs between 2015 and 2016 were followed for at least 24 months. Changes in ALBI were evaluated in the entire cohort and according to liver function and liver stiffness status at baseline.

Results

Four hundred ninety‐seven patients were enrolled. Exactly 96.92% were in Child–Pugh (CTP) class A, and 42% had grade 2 fibrosis. Median ALBI was −3.02, while 87.7 and 11.3% of patients were in ALBI grades 1 and 2, respectively. ALBI improved significantly over time, particularly in patients who had a worse ALBI at baseline. Exactly 77% of patients initially in ALBI grade 1 and 93.9% of those in ALBI grades 2–3 improved their ALBI score in different amounts. Improved ALBI was observed irrespective of CTP score at baseline. Median ALBI at baseline and after 24 months were −3.03 and −3.27 for CTP 5, 2.02 and −2.88 for CTP 6, and −1.59 and −2.84 for CTP >6. Similarly, a significant improvement in ALBI was observed within each stage of fibrosis at baseline.

Conclusion

ALBI was a good indicator of improved hepatic function in HCV patients with SVR after DAA therapy, able to identify changes even in those patients who started DAA therapy with well‐preserved function and mild fibrosis. This simple, objective, and noninvasive test should be evaluated in other clinical scenarios where liver function is relevant.

Comparative evaluation of the Geenius HCV supplemental assay and Inno-LIA HCV score assay in detecting anti-HCV antibodies

OBJECTIVE

This study compared two assays aimed at confirming the presence of anti-HCV antibodies (Ab) after a positive screening: Geenius HCV supplemental assay (Bio-Rad, Marne la Coquette, France) and the Inno-LIA HCV score assay (Fujirebio, Les Ulis, France).

MATERIAL AND METHODS

A total of 180 archived samples were investigated including 119 samples collected at different stages of HCV infection in 25 hemodialyzed patients who underwent HCV seroconversion, 14 samples from 4 commercial seroconversion panels, 47 Ab positive/HCV-RNA positive blood donations of which 7 showing an single reactivity in confirmatory assays. Samples were investigated and results were interpreted with the two assays according to the manufacturers' instructions.

RESULTS

Overall, Geenius and Inno-LIA were concordant for 84% (151/180) samples: 38 negative, 17 indeterminate and 96 positive. Of the 29 discrepant results, 26 were overclassified with Inno-LIA. HCV seroconversion was detected with Inno-LIA 4 and 7 days prior to Geenius in two panels. The high positive rate observed with Inno-LIA (64%) compared to Geenius (54%) was mainly due to low reactivities considered positive according to interpretation criteria, which could affect specificity.

CONCLUSION

Although HCV supplemental assays are not recommended for the diagnostic of HCV infection, which is primarily based on HCV-RNA testing, both assays are suitable as second line anti-HCV tests when Ab screening is positive and RNA testing cannot be performed. Moreover, Geenius system provides an objective result in less than 30minutes, which is compatible when a rapid diagnostic is required.

Hepatitis C Virus Epidemiology in Lithuania: Situation before Introduction of the National Screening Programme

In 2022, the Lithuanian health authorities decided to pay general practitioners a fee for performing serological tests for hepatitis C virus (HCV) antibodies in the population born from 1945 to 1994 once per life and annual HCV testing for PWID and HIV infected patients. This study aimed to assess trends in HCV-related mortality in the country and the prevalence of HCV infection among patients with liver diseases and evaluate possibilities of screening for HCV infection at a primary health care center. Age-standardized mortality rates in 2010–2020 were calculated for deaths caused by chronic hepatitis C and some liver diseases. Data on HCV infection among patients with liver cirrhosis, cancer and transplant patients were collected from the tertiary care hospital Kauno Klinikos. The prevalence of anti-HCV and risk factors of HCV infection was assessed among patients registered with the health care center in Klaipeda, where a pilot study of screening was performed. No steady trend in mortality was observed. Analysis of medical documentation showed that 40.5% of patients with liver cirrhosis, 49.7% with cancers and 36.9% of transplant patients were HCV infected. Over the year, 4867 patients were screened in the primary health care center. Positive anti-HCV prevalence was 1.7% (2.1% in men and 1.3% in women). Blood transfusion and being a blood donor before 1993 also having tattoos were associated with higher odds of HCV infection. The study revealed the active participation of individuals in HCV screening.

Hesperidin identified from Citrus extracts potently inhibits HCV genotype 3a NS3 protease

Background

Hepatitis C virus infection is the main cause of liver ailments across the globe. Several HCV genotypes have been identified in different parts of the world. Effective drugs for combating HCV infections are available but not affordable, particularly to infected individuals from resource-limited countries. Hence, cost-effective drugs need to be developed against important HCV drug targets. As Citrus fruits naturally contain bioactive compounds with antiviral activities, the current study was designed to identify antiviral inhibitors from Citrus fruit extracts against an important drug target, NS3 protease, of HCV genotype 3a which is found predominantly in South Asian countries.

Methods

The full-length NS3 protease alone and the NS3 protease domain in fusion with the cognate NS4A cofactor were expressed in Escherichia coli, and purified by chromatographic techniques. Using the purified protein as a drug target, Citrus extracts were evaluated in a FRET assay, and active ingredients, identified using ESI–MS/MS, were docked to observe the interaction with active site residues of NS3. The best interacting compound was further confirmed through the FRET assay as the inhibitor of NS3 protease.

Results

Fusion of the NS3 protease domain to the NS4A cofactor significantly improved the purification yield, and NS3-NS4A was functionally more active than the full-length NS3 alone. The purified protein (NS3-NS4A) was successfully employed in a validated FRET assay to evaluate 14 Citrus fruit extracts, revealing that the mesocarp extract of Citrus paradisi, and whole fruit extracts of C. sinesis, C. aurantinum, and C. reticulata significantly inhibited the protease activity of HCV NS3 protease (IC₅₀ values of 5.79 ± 1.44 µg/mL, 37.19 ± 5.92 µg/mL, 42.62 ± 6.89 µg/mL, and 57.65 ± 3.81 µg/mL, respectively). Subsequent ESI-MSⁿ analysis identified a flavonoid, hesperidin, abundantly present in all the afore-mentioned Citrus extracts. Importantly, docking studies suggested that hesperidin interacts with active site residues, and acts as a potent inhibitor of NS3 protease, exhibiting an IC₅₀ value of 11.34 ± 3.83 µg/mL.

Conclusions

A FRET assay was developed using NS3-NS4A protease, which was successfully utilized for the evaluation of Citrus fruit extracts. Hesperidin, a compound present in the Citrus extracts, was identified as the main flavonoid, which can serve as a cost-effective potent inhibitor of NS3 protease, and could be developed as a drug for antiviral therapy against HCV genotype 3a.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-022-03578-1.

Review of human pegivirus: Prevalence, transmission, pathogenesis, and clinical implication

Human pegivirus (HPgV-1), previously known as GB virus C (GBV-C) or hepatitis G virus (HGV), is a single-stranded positive RNA virus belonging to the genus Pegivirus of the Flaviviridae family. It is transmitted by percutaneous injuries (PIs), contaminated blood and/or blood products, sexual contact, and vertical mother-to-child transmission. It is widely prevalent in general population, especially in high-risk groups. HPgV-1 viremia is typically cleared within the first 1–2 years of infection in most healthy individuals, but may persist for longer periods of time in immunocompromised individuals and/or those co-infected by other viruses. A large body of evidences indicate that HPgV-1 persistent infection has a beneficial clinical effect on many infectious diseases, such as acquired immunodeficiency syndrome (AIDS) and hepatitis C. The beneficial effects seem to be related to a significant reduction of immune activation, and/or the inhabitation of co-infected viruses (e.g. HIV-1). HPgV-1 has a broad cellular tropism for lymphoid and myeloid cells, and preferentially replicates in bone marrow and spleen without cytopathic effect, implying a therapeutic potential. The paper aims to summarize the natural history, prevalence and distribution characteristics, and pathogenesis of HPgV-1, and discuss its association with other human viral diseases, and potential use in therapy as a biovaccine or viral vector.

Insights Into the Coinfections of Human Immunodeficiency Virus-Hepatitis B Virus, Human Immunodeficiency Virus-Hepatitis C Virus, and Hepatitis B Virus-Hepatitis C Virus: Prevalence, Risk Factors, Pathogenesis, Diagnosis, and Treatment

Human immunodeficiency virus, hepatitis B virus, and hepatitis C virus are three blood-borne viruses that can cause major global health issues by increasing severe morbidity. There is a high risk of coinfection with these viruses in individuals because of their same transmission routes through blood using shared needles, syringes, other injection equipment, sexual transmission, or even vertical transmission. Coinfection can cause various liver-related illnesses, non-hepatic organ dysfunction, followed by death compared to any of these single infections. The treatment of coinfected patients is complicated due to the side effects of antiviral medication, resulting in drug resistance, hepatotoxicity, and a lack of required responses. On the other hand, coinfected individuals must be treated with multiple drugs simultaneously, such as for HIV either along with HBV or HCV and HBV and HCV. Therefore, diagnosing, treating, and controlling dual infections with HIV, HBV, or HCV is complicated and needs further investigation. This review focuses on the current prevalence, risk factors, and pathogenesis of dual infections with HIV, HBV, and HCV. We also briefly overviewed the diagnosis and treatment of coinfections of these three blood-borne viruses.

High success rates for the use of ombitasvir/paritaprevir/ritonavir containing regimens in treatment of naïve and experienced chronic hepatitis C genotype 4: Real world results

INTRODUCTION AND AIMS

Treatment of hepatitis C virus (HCV) genotype 4 patient with fixed dose combination of ombitasvir-paritaprevir-ritonavir plus ribavirin (OBV/rPTV/RBV) has been proven efficacy and safety in many clinical trials. The current study reports the efficacy and safety of OBV/rPTV/RBV (for treatment-naïve), and OBV/rPTV/RBV/sofosbuvir (SOF) (for treatment-experienced), in chronic HCV genotype 4 patients in real life settings.

METHODS

Prospective cohort study including all adult chronic HCV genotype 4 patients who were scheduled to receive OBV/rPTV/RBV ± SOF for 12 or 24 weeks in New Cairo Viral Hepatitis Treatment Center. The primary efficacy endpoint was a virologic response at posttreatment week 12 (SVR12). Changes in hematological parameters, liver biochemical profile and fibrosis-4 index (FIB-4), as well as clinical and laboratory adverse events (AEs) across follow up visits (week 4, end of treatment [EOT], and SVR12), were recorded.

RESULTS

Our study included 325 patients (age; 47.63 ± 12.63 years, 55.38% [n = 180] men). Most of the included patients (89.85%, n = 292) were treatment naïve and only 7% (n = 23) had liver cirrhosis. Overall, SVR12 was attained by 98.44% (316 of 321) of the patients; 97.15% (307 of 316) of patients who received 12 weeks of OBV/rPTV/RBV ± SOF and 100% (9 of 9) of patients who received 24 weeks of OBV/rPTV/RBV as assessed by modified intention to treat analysis. There was a significant improvement of baseline alanine aminotransferase, aspartate aminotransferase, hemoglobin, FIB-4 at SVR12 (P < 0.05). The most common reported AEs were anemia (n = 106), fatigue (n = 41) and elevated indirect bilirubin (n = 37).

CONCLUSION

OBV/rPTV/RBV (±SOF) is a highly effective therapy for chronic HCV patients in real life settings.

Virus-Like Particles Containing the E2 Core Domain of Hepatitis C Virus Generate Broadly Neutralizing Antibodies in Guinea Pigs

A vaccine to prevent hepatitis C virus (HCV) infection is urgently needed for use alongside direct-acting antiviral drugs to achieve elimination targets. We have previously shown that a soluble recombinant form of the glycoprotein E2 ectodomain (residues 384 to 661) that lacks three variable regions (Δ123) is able to elicit a higher titer of broadly neutralizing antibodies (bNAbs) than the parental form (receptor-binding domain [RBD]). In this study, we engineered a viral nanoparticle that displays HCV glycoprotein E2 on a duck hepatitis B virus (DHBV) small surface antigen (S) scaffold. Four variants of E2-S virus-like particles (VLPs) were constructed: Δ123-S, RBD-S, Δ123A7-S, and RBDA7-S; in the last two, 7 cysteines were replaced with alanines. While all four E2-S variant VLPs display E2 as a surface antigen, the Δ123A7-S and RBDA7-S VLPs were the most efficiently secreted from transfected mammalian cells and displayed epitopes recognized by cross-genotype broadly neutralizing monoclonal antibodies (bNMAbs). Both Δ123A7-S and RBDA7-S VLPs were immunogenic in guinea pigs, generating high titers of antibodies reactive to native E2 and able to prevent the interaction between E2 and the cellular receptor CD81. Four out of eight animals immunized with Δ123A7-S elicited neutralizing antibodies (NAbs), with three of those animals generating bNAbs against 7 genotypes. Immune serum generated by animals with NAbs mapped to major neutralization epitopes located at residues 412 to 420 (epitope I) and antigenic region 3. VLPs that display E2 glycoproteins represent a promising vaccine platform for HCV and could be adapted to large-scale manufacturing in yeast systems.

IMPORTANCE There is currently no vaccine to prevent hepatitis C virus infection, which affects more than 71 million people globally and is a leading cause of progressive liver disease, including cirrhosis and cancer. Broadly neutralizing antibodies that recognize the E2 envelope glycoprotein can protect against heterologous viral infection and correlate with viral clearance in humans. However, broadly neutralizing antibodies are difficult to generate due to conformational flexibility of the E2 protein and epitope occlusion. Here, we show that a VLP vaccine using the duck hepatitis B virus S antigen fused to HCV glycoprotein E2 assembles into virus-like particles that display epitopes recognized by broadly neutralizing antibodies and elicit such antibodies in guinea pigs. This platform represents a novel HCV vaccine candidate amenable to large-scale manufacture at low cost.

Does Hepatitis C Virus Treatment by Directly Acting Antivirals Obligate Shifting Patients with Type 2 Diabetes from Oral Hypoglycemic Drugs to Insulin Therapy?

PURPOSE

The aim of the present work was to investigate whether hepatitis C virus treatment by directly acting antivirals obligate shifting patients with type 2 diabetes from oral hypoglycemic drugs to insulin therapy.

METHODS

This was a prospective study including 92 treatment-naïve patients with chronic hepatitis C virus infection and type 2 diabetes who were eligible for treatment with directly acting antivirals (sofosbuvir + daclatasvir ± ribavirin). Patients in the study were divided into two groups; group 1 included 22 patients on insulin therapy and group 2 included 70 patients on oral antidiabetic medications. Patients were advised to keep on their anti-diabetic treatment.

RESULTS

All our patients achieved sustained virologic response with significantly lower HbA_1c 12 weeks after the end of therapy (p. values 0.001 for group 1 and group 2). There was no statistically significant difference in HbA_1c level post-treatment between both groups (p. value 0.352).

CONCLUSION

Achievement of sustained virologic response using interferon free, directly acting antivirals-based regimen was associated with significantly lower HbA_1c 12 weeks after the end of therapy. The type of treatment used for type 2 diabetes (oral drugs or insulin) did not affect improved glycemic control observed after achieving sustained virologic response.

Aptamer-Based Antibacterial and Antiviral Therapy against Infectious Diseases

Nucleic acid aptamers are single-stranded DNA or RNA molecules selected in vitro that can bind to a broad range of targets with high affinity and specificity. As promising alternatives to conventional anti-infective agents, aptamers have gradually revealed their potential in the combat against infectious diseases. This article provides an overview on the state-of-art of aptamer-based antibacterial and antiviral therapeutic strategies. Diverse aptamers targeting pathogen-related components or whole pathogenic cells are summarized according to the species of microorganisms. These aptamers exhibited remarkable in vitro and/or in vivo inhibitory effect for pathogenic invasion, enzymatic activities, or viral replication, even for some highly drug-resistant strains and biofilms. Aptamer-mediated drug delivery and controlled drug release strategies are also included herein. Critical technical barriers of therapeutic aptamers are briefly discussed, followed by some future perspectives for their implementation into clinical utility.

Reported Barriers to Hepatitis C Treatment among Pregnant and Early-Parenting Mothers Undergoing Substance Use Disorder Treatment in One U.S. State

Nationwide, the prevalence of the hepatitis C virus (HCV) has risen in recent years. At least 90% of infected persons must be treated to achieve global elimination targets. The current study aimed to explore barriers to, and facilitators of, direct-acting antiviral (DAA) HCV treatment uptake amongst pregnant and early-parenting women undergoing comprehensive substance use treatment. Twenty participants with documented HCV antibody positivity were recruited from two substance use treatment centers in central Kentucky. Semi-structured interviews were conducted to explore knowledge about HCV, previous experiences, and intentions to seek care. Themes were extracted using an inductive analytical approach. Most participants were aware of the dangers posed by HCV infection. However, there was a high degree of misinformation about transmission mechanisms and treatment eligibility requirements. Low priority for HCV treatment also surfaced as a barrier to treatment uptake. Participants reported being unable to seek care due to time and resource limitations in the presence of a highly demanding treatment process. Findings from the current study suggest that more work is needed to eliminate residual barriers that limit access to HCV treatment among pregnant and early-parenting women in treatment for substance use disorder.

Oral Zinc Supplementation Decreases the Risk of HCC Development in Patients With HCV Eradicated by DAA

We have reported that the plasma zinc concentration gradually decreases with the progression of fibrosis and is related to hepatocellular carcinoma (HCC) development. The aim of this study was to examine the impact of the zinc concentration on HCC development (study 1) and the relationship between zinc intake and HCC development (study 2) in patients with hepatitis C virus (HCV) eradicated by direct‐acting antivirals (DAAs). A total of 599 sustained virological response (SVR) patients treated with DAAs without a history of HCC were retrospectively analyzed in this study. Eighty patients received supplemental zinc (Zn treatment group), and 519 patients did not receive zinc (no Zn treatment group). In study 1, the cumulative incidence rate of HCC was compared between the Zn treatment group and the no Zn treatment group. In study 2, the risk factors for HCC development were examined in the no Zn treatment group. In study 1, in the Zn treatment group, HCC did not develop during follow‐up, and the cumulative risk of HCC was significantly lower in the Zn treatment group than in the no Zn treatment group (P = 0.048). In study 2, the 1‐year and 3‐year cumulative incidence rates of HCC were 1.8% and 5.6%, respectively. The risk factors for HCC identified by multivariate analysis were male sex, cirrhosis, low platelet count before treatment, and low serum zinc concentration 12 weeks after the end of DAA therapy. Conclusion: The Zn concentration is related to HCC development in patients with HCV eradicated by DAA therapy. Oral zinc supplementation is recommended as a means of suppressing HCC development in patients who have achieved SVR.

Prevalence, diagnosis, and treatment of hepatitis C in Mainland China

Infection with the hepatitis C virus (HCV) is a major cause of liver disease and hepatocellular carcinoma in China. Rapid economic development has had an enormous impact on the epidemiology and treatment of hepatitis C. The prevalence of anti-HCV antibodies in Mainland China is approximately 0.91%, and use of injected drugs has become the main route of HCV transmission in China. Reimbursement for 3 direct-acting antivirals (DAAs) has been approved by the National Medical Insurance scheme in China, which ensures the accessibility of treatment for an HCV infection. To improve the awareness of treatments for hepatitis C among medical personnel and the rate of in-hospital screening for HCV, the Chinese Medical Association has formulated guidelines for the diagnosis and treatment of hepatitis C and a process of in-hospital screening for hepatitis C in China. These efforts have standardized the screening, diagnosis, treatment, and management of hepatitis C. Based on the international strategy for micro-elimination of hepatitis C, China has also screened and treated groups at risk of hepatitis C infection, and this has reduced the number of the infected. The current review describes the status of and issues with the prevalence, diagnosis, and treatment of hepatitis C in Mainland China as part of the global effort to eliminate viral hepatitis by 2030.

Micro-Elimination: Updated Pathway to Global Elimination of Hepatitis C in Small Communities and Industrial Settings during the COVID 19 Pandemic

BACKGROUND

In response to the goal of the World Health Organisation to eliminate hepatitis C virus infections by 2030, Romania is striving for national elimination. An already successful micro-elimination project was expanded to test-and-treat specific populations and at-risk groups. The aim of this project was to identify the individuals with HCV infection in disadvantaged regions who do not have proper medical care access.

MATERIALS AND METHODS

Our two-arm interventional cross-sectional study used rapid anti-HCV antibody testing on two population groups from the Romanian southwestern region of Oltenia, approached between September 2020 and May 2021. The first group consisted of predominantly over 40 years old individuals, recruited through five family doctors from two medium-sized towns (community lot-CL). We approached a second group, aged 18-65, through 11 medical offices of five large factories in the same region (industry lot, IL). A 12-items questionnaire was given to each participant, to determine risk factors and record demographic data. Eligible patients initiated antiviral therapy using direct-acting antivirals (DAAs).

RESULTS

We enrolled 15,383 individuals between all 16 locations. The overall prevalence by antibody testing was 0.77% (119 cases). Of these, 57 subsequently received treatment with DAAs. We identified blood transfusions as a risk factor within the CL. Participants in the IL reported a relatively high risk for the following situations: sharing of personal hygiene belongings with another person, performing previous blood transfusions, dental interventions and previous surgery.

CONCLUSIONS

In this global context, the use of micro-elimination allows interventions to be faster and more efficient. This is possible by targeting smaller and specific HCV risk groups.

Values and preferences for hepatitis C self-testing among the general population and healthcare workers in Rwanda

Background

In 2018, Rwanda launched a 5-year hepatitis C virus (HCV) elimination plan as per the World Health Organization global targets to eliminate HCV by 2030. To improve awareness of HCV status, strategies are needed to ensure easy access to HCV testing by as-yet unreached populations. HCV-self-testing, an innovative strategy, could further increase HCV testing uptake. This assessment explores perceptions around HCV self-testing among members of the public and healthcare workers in Rwanda.

Methods

A qualitative study was undertaken in Masaka District Hospital, comprising individual interviews, group interviews and participatory action research (PAR) activities. Purposive and snowball sampling methods guided the selection of informants. Informed consent was obtained from all participants. A thematic analysis approach was used to analyse the findings.

Results

The participants comprised 36 members of the public and 36 healthcare workers. Informants appreciated HCV self-testing as an innovative means of increasing access to HCV testing, as well as an opportunity to test privately and subsequently autonomously decide whether to seek further HCV care. Informants further highlighted the need to make HCV self-testing services free of charge at the nearest health facility. Disadvantages identified included the lack of pre/post-test counselling, as well as the potential psychosocial harm which may result from the use of HCV self-testing.

Conclusion

HCV self-testing is perceived to be an acceptable method to increase HCV testing in Rwanda. Further research is needed to assess the impact of HCV self-testing on HCV cascade of care outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06773-6.

Hepatitis C virus E2 envelope glycoprotein produced in Nicotiana benthamiana triggers humoral response with virus-neutralizing activity in vaccinated mice

Chronic infection with hepatitis C virus (HCV) remains a leading cause of liver-related pathologies and a global health problem, currently affecting more than 71 million people worldwide. The development of a prophylactic vaccine is much needed to complement the effective antiviral treatment available and achieve HCV eradication. Current strategies focus on increasing the immunogenicity of the HCV envelope glycoprotein E2, the major target of virus-neutralizing antibodies, by testing various expression systems or manipulating the protein conformation and the N-glycosylation pattern. Here we report the first evidence of successful production of the full-length HCV E2 glycoprotein in Nicotiana benthamiana, by using the Agrobacterium-mediated transient expression technology. Molecular and functional analysis showed that the viral protein was correctly processed in plant cells and achieved the native folding required for binding to CD81, one of the HCV receptors. N-glycan analysis of HCV-E2 produced in N. benthamiana and mammalian cells indicated host-specific trimming of mannose residues and possibly, protein trafficking. Notably, the plant-derived viral antigen triggered a significant immune response in vaccinated mice, characterized by the presence of antibodies with HCV-neutralizing activity. Together, our study demonstrates that N. benthamiana is a viable alternative to costly mammalian cell cultures for the expression of complex viral antigens and supports the use of plants as cost-effective production platforms for the development of HCV vaccines.

The contribution of bovines to human health against viral infections

In the last 40 years, novel viruses have evolved at a much faster pace than other pathogens. Viral diseases pose a significant threat to public health around the world. Bovines have a longstanding history of significant contributions to human nutrition, agricultural, industrial purposes, medical research, drug and vaccine development, and livelihood. The life cycle, genomic structures, viral proteins, and pathophysiology of bovine viruses studied in vitro paved the way for understanding the human counterparts. Calf model has been used for testing vaccines against RSV, papillomavirus vaccines and anti-HCV agents were principally developed after using the BPV and BVDV model, respectively. Some bovine viruses-based vaccines (BPIV-3 and bovine rotaviruses) were successfully developed, clinically tried, and commercially produced. Cows, immunized with HIV envelope glycoprotein, produced effective broadly neutralizing antibodies in their serum and colostrum against HIV. Here, we have summarized a few examples of human viral infections for which the use of bovines has contributed to the acquisition of new knowledge to improve human health against viral infections covering the convergence between some human and bovine viruses and using bovines as disease models. Additionally, the production of vaccines and drugs, bovine-based products were covered, and the precautions in dealing with bovines and bovine-based materials.

Knowledge among patients with Hepatitis C initiating on direct-acting antiviral treatment in rural Rwanda: A prospective cohort study

Background

Curative direct-acting antiviral treatment (DAA) has made it plausible to implement hepatitis C elimination interventions. However, poor hepatitis C knowledge among patients could impede the effectiveness of screening and treatment programs.

Objective

We assessed knowledge on hepatitis C among rural Rwandans initiating DAA treatment for hepatitis C in a prospective cohort.

Methods

We administered 15 true-false statements before treatment initiation and during one follow-up visit occurring either 1 or 2 months after treatment initiation. We assessed the average number of correct responses per patient, the proportion of correct responses to individual statements, pre-treatment predictors of knowledge, and whether post-initiation knowledge was associated with time since treatment initiation, quality of care, or adherence.

Results

Among 333 patients who answered knowledge questions before treatment initiation, 325 (97.6%) were re-assessed at a post-initiation visit. Pre-initiation, 72.1% knew hepatitis C was curable, 61.9% knew that hepatitis C could cause liver damage or cancer, and 42.3% knew that people with hepatitis C could look and feel fine. The average number of correct responses was 8.1 out of 15 (95% CI: 7.8–8.5), but was significantly lower among those with low educational attainment or with low literacy. Post-initiation, correct responses increased by an average of 2.0 statements (95% CI: 1.6, 2.4, p-value <0.001). Many patients still mistakenly believed that hepatitis C could be transmitted through kissing (66.5%), eating utensils (44.1%), handshakes (34.8%), and hugs (34.8%). Post-initiation knowledge is inversely associated with self-reported quality of care and unassociated with self-reported adherence.

Conclusion

Although knowledge improved over time, key gaps persisted among patients. Accessible public education campaigns targeted to low-literacy populations emphasizing that hepatitis C can be asymptomatic, has severe consequences, and is curable could promote participation in mass screening campaigns and linkage to care. Visual tools could facilitate clinician-provided patient education.

Liver and cardiovascular mortality after hepatitis C virus eradication by DAA: Data from RESIST-HCV cohort

Real-world evidence on the course of Hepatitis C Virus (HCV) chronic liver disease after Sustained Virologic Response (SVR) obtained with direct-acting antiviral drugs (DAAs) are still limited, and the effects on mortality remain unclear. We evaluated the post-treatment survival of 4307 patients in the RESIST-HCV cohort (mean age 66.3 ± 11.6 years, 56.9% males, 24.7% chronic hepatitis, 66.9% Child-Pugh A cirrhosis and 8.4% Child-Pugh B cirrhosis) treated with DAAs between March 2015 and December 2016 and followed for a median of 73 weeks (range 16-152). Proportional cause-specific hazard regression for competing risks was used to evaluate the survival and to assess the predictors of liver and cardiovascular death. Overall, 94.7% of patients achieved SVR while 5.3% were HCV RNA-positive at last follow-up. Sixty-three patients (1.4%) died during the observation period. SVR was associated with a decreased risk of liver mortality (hazard ratio,HR0.09, beta -2.37, p < .001). Also, platelet count (HR 0.99, beta-0.01, p = .007) and albumin value (HR 0.26, beta -1.36 p = .001) were associated with liver mortality by competing risk analysis. SVR was associated with a reduced risk of cardiovascular mortality regardless of presence of cirrhosis (HR 0.07, beta-2.67, p < .001). Presence of diabetes (HR 3.45, beta 1.24, p = .014) and chronic kidney disease class ≥3 (HR 3.60, beta 1.28, p = 0.016) were two factors independently associated with higher risk of cardiovascular mortality. Patients with SVR to a DAA therapy have a better liver and cardiovascular survival, and the effects of HCV eradication are most evident in patients with compensated liver disease.

A Review of Hepatitis B Virus and Hepatitis C Virus Immunopathogenesis

Despite the advances in therapy, hepatitis B virus (HBV) and hepatitis C virus (HCV) still represent a significant global health burden, both as major causes of cirrhosis, hepatocellular carcinoma, and death worldwide. HBV is capable of incorporating its covalently closed circular DNA into the host cell's hepatocyte genome, making it rather difficult to eradicate its chronic stage. Successful viral clearance depends on the complex interactions between the virus and host's innate and adaptive immune response. One encouraging fact on hepatitis B is the development and effective distribution of the HBV vaccine. This has significantly reduced the spread of this virus. HCV is a RNA virus with high mutagenic capacity, thus enabling it to evade the immune system and have a high rate of chronic progression. High levels of HCV heterogeneity and its mutagenic capacity have made it difficult to create an effective vaccine. The recent advent of direct acting antivirals has ushered in a new era in hepatitis C therapy. Sustained virologic response is achieved with DAAs in 85-99% of cases. However, this still leads to a large population of treatment failures, so further advances in therapy are still needed. This article reviews the immunopathogenesis of HBV and HCV, their properties contributing to host immune system avoidance, chronic disease progression, vaccine efficacy and limitations, as well as treatment options and common pitfalls of said therapy.

Structural perspectives on HCV humoral immune evasion mechanisms

The molecular mechanisms of hepatitis C virus (HCV) persistence and pathogenesis are poorly understood. The design of an effective HCV vaccine is challenging despite a robust humoral immune response against closely related strains of HCV. This is primarily because of the huge genetic diversity of HCV and the molecular evolution of various virus escape mechanisms. These mechanisms are steered by the presence of a high mutational rate in HCV, structural plasticity of the immunodominant regions on the virion surface of diverse HCV genotypes, and constant amino acid substitutions on key structural components of HCV envelope glycoproteins. Here, we review the molecular basis of neutralizing antibody (nAb)-mediated immune response against diverse HCV variants, HCV-steered humoral immune evasion strategies and explore the essential structural elements to consider for designing a universal HCV vaccine. Structural perspectives on key escape pathways mediated by a point mutation within the epitope, allosteric modulation of the epitope by distant mutations and glycan shift on envelope glycoproteins will be highlighted (abstract graphic).

Changes of liver stiffness measured by magnetic resonance elastography during direct-acting antivirals treatment in patients with chronic hepatitis C

Almost all patients achieved sustained virological response (SVR) by direct-acting antivirals (DAA) therapy, but it is not clear as to what extent DAA therapy affects changes in liver fibrosis after achieving SVR. In this study, we investigated the changes of liver stiffness by magnetic resonance elastogaraphy (MRE) during DAA therapy. A total of 308 patients were enrolled in the study. Liver stiffness was measured twice before and after DAA treatment using MRE and time-course change of liver stiffness was investigated. The median (interquartile range) values for liver stiffness were 4.2 (3.2-6.1) kPa at baseline and 3.3 (2.6-4.8) kPa at SVR, demonstrating a significant improvement (p < .01). A total of 44% of patients had no improvement in liver stiffness despite achieving SVR. In patients with advanced fibrosis (lower level of albumin [Alb] or histological fibrosis stage F4), it was difficult to improve liver stiffness. Except for Alb, there were no blood tests associated with nonimprovement in liver stiffness, making these cases difficult to predict. In conclusion, despite obtaining SVR, improvement in liver stiffness could not be obtained in some cases, especially in patients with advanced fibrosis. In these patients, liver stiffness must be followed even if SVR is obtained.

HCV virology and diagnosis

Hepatitis C virus (HCV) infection is a major cause of severe liver disease including chronic hepatitis, cirrhosis and hepatocellular carcinoma. The HCV burden in public health is estimated at about 71 million people worldwide by World Health Organization (WHO) with at least 400,000 people that died every year from HCV disease [1]. New hepatitis C treatments with oral direct-acting antivirals (DAAs) showing high rates of response, with short treatment duration [2] have been available. HCV can now be eradicated with minimal side effects. Unfortunately, there is no vaccine yet available, but the development of a safe prophylactic vaccine remains a medical priority [3]. For this purpose, Hepatitis B-C subviral envelope particles can be produced by industrialized procedure. It seems to be very promising as this HBV-HCV vaccine candidate has been shown to elicit a broadly cross neutralizing activity against HCV [4]. Despite this revolution in the HCV-treatment, one of major challenge to achieve a global eradication of HCV remains to reduce the under diagnosis. The low rate of diagnosis is a major obstacle in resources limited countries and is mainly due to the cost of molecular tools, that are essential to diagnose and follow chronic HCV infection. In another hand, the mild clinical symptoms observed in HCV chronic disease, may explain that the majority of HCV infected individuals are unaware of their infection, because HCV testing is not generalized, like it is for HIV. HCV was discovered in 1989 after many years of work, by several researchers, who recently obtained the Nobel price [5-7]. This major discovery allowed the description of the HCV genome and later on of the virus replication and cell cycle, and also, importantly, the development of diagnostic tests for the detection of HCV antibodies (Ab) and RNA who were a priority in transfusion. In this review, we will try to get into the virology and cell biology of HCV. Thereafter, we will discuss the different categories of laboratory tests to diagnose/explore HCV infected subjects.

Global research status of gastroenterology and hepatology: A bibliometrics study

BACKGROUND

There are no reports on global research status of gastroenterology and hepatology (GI). This study was conducted to reveal the current global research status and trends in GI.

METHODS

Articles published during 2009 to 2018 in international GI journals were retrieved from the PubMed database. The top 20 countries by output were determined. The gross domestic product (GDP) of each country was also retrieved to figure out the correlation between outputs in GI and economy. The 5 highest-ranking countries were compared in the number of total articles, articles per capita, articles published in top journals, the accumulated impact factor (IF), and average IF. Total articles and articles per capita of the 5 countries were conducted time-trend analysis. The frequently-used terms in titles and abstracts of articles published in 2009 and 2018 were retrieved to conduct co-occurrence analysis to figure out the change of research highlights in GI.

RESULTS

A total of 120,267 articles were included, of which 116,485 articles were from 20 highest-output countries. There was a positive correlation between output and GDP (r = 0.921, P < .001). The USA, Japan, China, Italy, and the UK were the 5 highest-ranking countries. The USA was the largest contributor with 26,215 articles, accounting for 17.4% of the total, but with no significant increasing trend (P = .122). Other 4 countries all showed increasing trends (all P < .001). For articles per capita, Italy ranked 1st among the 5 countries with 1591.0 articles per 10 million. The USA showed a decreasing trend (P = .026), other 4 countries all showed increasing trends (all P < .001). The UK had the highest average IF (6.685). For change of research highlights, it is more inclined to research of endoscopy, inflammatory bowel diseases, and nonalcoholic fatty liver disease.

CONCLUSION

It is delightful that the global research output in GI field would be continuingly increased as the major highest-output countries showed increasing trends. However, the developing countries fell behind both in quantity and quality when compared with developed countries.

A Lay-User Assessment of Hepatitis C Virus Self-Testing Device Usability and Interpretation in Johannesburg, South Africa

Only 20% of people with hepatitis C virus (HCV) know their status. In low-income countries diagnosis is under 10%. Self-testing for HCV antibodies (HCVST) could expand the coverage of HCV testing services. Currently, there are no stringent regulatory authority (SRA) approved HCVSTs, therefore lay-user usability of three prototype kits was assessed. This was a cross-sectional observational study conducted with 171 (CareStart n = 60, Bioline n = 52, First Response n = 59) participants. Participants were given one of the three HCVST kits with only instructions for use (IFU) and asked to perform the test in front of a professional trained in rapid diagnostic tests (RDT). Usability indices were calculated based on the correctness of performing each step of the product-specific process followed by contrived results interpretation and a post-test interview. The usability index was 93.9% for CareStart, 90.7% for Bioline and 94.9% for First Response. Most errors were on incorrect handwashing, sample collection and transfer to the test device. An average of 93.1% of contrived results were correctly interpreted, with most errors related to interpreting invalid results. Most participants (n = 167) stated they would visit a clinic after a positive result. With negative results, nearly half (28/60 (46.7%)) stated they should condomize, while just over two-thirds of participants that used Bioline (35/52 (67.3%)) and First Response (38/59 (64.4%)) said they should re-test. Most participants (n = 162) found the devices easy to use. Participants liked that self-testing was fast, private and convenient, however there were some confusion with IFU steps and pictures, finger-pricking with the lancet, collecting blood after the finger-prick, and transferring the sample/buffer. Prototype HCVST kits exhibit high usability and result interpretation by lay-users, and should be considered for SRA approval.

Acceptability and Usability of HCV Self-Testing in High Risk Populations in Vietnam

HIV self-testing has emerged as a safe and effective approach to increase the access to and uptake of HIV testing and treatment, especially for key populations. Applying self-testing to hepatitis C virus (HCV) may also offer an additional way to address low coverage of HCV testing and to accelerate elimination efforts. To understand the potential for HCV self-testing (HCVST), an observational study was conducted to assess the acceptability and usability of the OraQuick^® HCV Self-Test (prototype) among people who inject drugs (PWID) and men who have sex with men (MSM) in Thai Nguyen, a province in northern Vietnam. A total of 105 PWID and 104 MSM were eligible and agreed to participate in the study. Acceptability, defined as the proportion of participants among eligible subjects who agreed to participate in the study, was 92.9% in PWID and 98.6% in MSM. Compared to MSM, PWID were older (median age: 45 vs. 22 years; p < 0.0001) and had a lower education level (high school and college: 38.1% vs. 100%; p < 0.0001). HCVST usability was high among MSM with fewer observed mistakes, difficulties, or participants requiring assistance (33.7%, 28.8%, and 17.3%, respectively) compared to PWID (62.9%, 53.3%, and 66.7%, respectively; all p < 0.0001)). Inter-reader and inter-operator agreement were good in both groups (Kappa coefficient range: 0.61–0.99). However, the concordance between HCVST and study staff -read or performed HCV testing was lower among PWID than MSM (inter-reader concordance 88.6% vs. 99.0% and inter-operator concordance 81.9% vs. 99%). Overall, HCVST was highly acceptable with moderate to high usability among PWID and MSM in Thai Nguyen. Efforts to provide support and assistance may be needed to optimize performance, particularly for PWID populations and for those who are older and with lower literacy or education levels.

A real-life study on the impact of direct-acting antivirals in the treatment of chronic hepatitis C in liver transplant recipients at two university centers in Northeastern Brazil

The efficacy of direct-acting antivirals (DAAs) in the treatment of chronic hepatitis C (CHC) in liver transplant recipients is poorly understood, and several factors, including immunosuppression, drug interactions, elevated viraemia, and intolerance to ribavirin (RBV), can reduce cure rates. We conducted a real-life study on liver transplant recipients with CHC treated with a combination of sofosbuvir (SOF) and daclatasvir (DCV) or simeprevir (SIM), with or without RBV, followed-up for 12 to 24 weeks. The treatment effectiveness was assessed by determining the sustained virological response (SVR) rates at 12 or 24 weeks after the treatment cessation. Eighty-four patients were evaluated, with a mean age of 63.4 ± 7.4 years, HCV genotype 1 being the most prevalent (63.1%). Nineteen patients (22.7%) had mild fibrosis (METAVIR < F2) and 41 (48.8%) significant fibrosis (METAVIR ≥ F2). The average time between liver transplantation and the start of treatment was 4 years (2.1-6.6 years). The SOF + DCV regimen was used in 58 patients (69%). RBV in combination with DAAs was used in seven patients (8.3%). SVR was achieved in 82 patients (97.6%), and few relevant adverse events could be attributed to DAA therapy, including a patient who stopped treatment due to a headache. There was a significant reduction in ALT, AST, GGT and FA levels, or the APRI index after 4 weeks of treatment, which remained until 12/24 weeks post-treatment. DAA treatment of CHC in liver-transplanted patients achieved a high SVR rate and resulted in the normalization of serum levels of liver enzymes.

Required concentration index quantifies effective drug combinations against hepatitis C virus infection

Successful clinical drug development requires rational design of combination treatments based on preclinical data. Anti-hepatitis C virus (HCV) drugs exhibit significant diversity in antiviral effect. Dose-response assessments can be used to determine parameters profiling the diverse antiviral effect during combination treatment. In the current study, a combined experimental and mathematical approaches were used to compare and score different combinations of anti-HCV treatments. A “required concentration index” was generated and used to rank the antiviral profile of possible double- and triple-drug combinations against HCV genotype 1b and 2a. Rankings varied based on target HCV genotype. Interestingly, multidrug (double and triple) treatment not only augmented antiviral activity, but also reduced genotype-specific efficacy, suggesting another advantage of multidrug treatment. The current study provides a quantitative method for profiling drug combinations against viral genotypes, to better inform clinical drug development.

Differential Roles for Diploid and Polyploid Hepatocytes in Acute and Chronic Liver Injury

Hepatocytes are the primary functional cells of the liver that perform essential roles in homeostasis, regeneration, and injury. Most mammalian somatic cells are diploid and contain pairs of each chromosome, but there are also polyploid cells containing additional sets of chromosomes. Hepatocytes are among the best described polyploid cells, with polyploids comprising more than 25 and 90% of the hepatocyte population in humans and mice, respectively. Cellular and molecular mechanisms that regulate hepatic polyploidy have been uncovered, and in recent years, diploid and polyploid hepatocytes have been shown to perform specialized functions. Diploid hepatocytes accelerate liver regeneration induced by resection and may accelerate compensatory regeneration after acute injury. Polyploid hepatocytes protect the liver from tumor initiation in hepatocellular carcinoma and promote adaptation to tyrosinemia-induced chronic injury. This review describes how ploidy variations influence cellular activity and presents a model for context-specific functions for diploid and polyploid hepatocytes.

Facial and bilateral lower extremity edema due to drug-drug interactions in a patient with hepatitis C virus infection and benign prostate hypertrophy: A case report

BACKGROUND

New direct-acting antivirals (DAAs)-based anti-hepatitis C virus (HCV) therapies are highly effective in patients with HCV infection. However, safety data are lacking regarding HCV treatment with DAAs and drugs for comorbidities.

CASE SUMMARY

Herein, we reported a case of HCV-infection in a 46-year-old man with benign prostatic hypertrophy. The patient received sofosbuvir/velpatasvir as well as methadone maintenance therapy for drug abuse. The viral load became negative at week 1 post treatment. He developed facial and bilateral lower extremity edema 48 h after starting receiving tamsulosin. Edema disappeared 10 d after treatment with oral furosemide and spironolactone.

CONCLUSION

In conclusion, this is the first case of an acute edema in the course of treatment with new DAAs, methadone and tamsulosin. These agents are useful in clinical management of patients with HCV infection, particularly in men with benign prostatic hypertrophy. Clinicians should be aware of potential drug-drug interactions in this subset of patients.

Reversal of T Cell Exhaustion in Chronic HCV Infection

The long-term consequences of T cell responses’ impairment in chronic HCV infection are not entirely characterized, although they may be essential in the context of the clinical course of infection, re-infection, treatment-mediated viral clearance and vaccine design. Furthermore, it is unclear whether a complete reinvigoration of HCV-specific T cell response may be feasible. In most studies, attempting to reverse the effects of compromised immune response quality by specific blockades of negative immune regulators, a restoration of functional competence of HCV-specific T cells was shown. This implies that HCV-induced immune dysfunction may be reversible. The advent of highly successful, direct-acting antiviral treatment (DAA) for chronic HCV infection instigated investigation whether the treatment-driven elimination of viral antigens restores T cell function. Most of studies demonstrated that DAA treatment may result in at least partial restoration of T cell immune function. They also suggest that a complete restoration comparable to that seen after spontaneous viral clearance may not be attained, pointing out that long-term antigenic stimulation imprints an irreversible change on the T cell compartment. Understanding the mechanisms of HCV-induced immune dysfunction and barriers to immune restoration following viral clearance is of utmost importance to diminish the possible long-term consequences of chronic HCV infection.

Quadruple Therapy Offers High SVR Rates in Patients with HCV Genotype 4 with Previous Treatment Failure

BACKGROUND AND AIMS

Direct-acting antivirals (DAAs) have made a revolution in hepatitis C virus (HCV) treatment with promising reduction of HCV infection and disease morbidities. However, unfortunately, treatment failure still occurs in about 5-15% of patients treated with DAA-based combination regimens. The primary aim of the study was to assess the efficacy and safety of a quadruple regimen of (sofosbuvir, daclatasvir, and simeprevir with a weight-based ribavirin) in chronic HCV DAAs-experienced patients.

METHODS

This observational, open-label prospective study was carried out on 103 genotype 4 hepatitis C virus-infected patients who failed to achieve SVR12 after sofosbuvir-daclatasvir with or without ribavirin. Patients were treated for three months with sofosbuvir (400 mg), daclatasvir (60 mg), and simeprevir (150 mg) with a weight-based ribavirin dosage (1000-1200 mg/d). Response to treatment was determined by quantitative PCR for HCV at 3 months after the end of treatment (SVR12), and adverse events during the treatment were recorded.

RESULTS

SVR was achieved in 100 patients (97.1%) at week 12 after treatment. No dangerous or life-threatening adverse events were recorded.

CONCLUSIONS

Retreatment of HCV genotype 4 patients with quadruple therapy is a good therapeutic option and achieves high response rates with minimal side effects.

High sustained viral response among HCV genotype 3 patients with advanced liver fibrosis: real-world data of HCV elimination program in Georgia

Objective

In 2015, Georgia launched HCV elimination program. Initially, patients with advanced liver disease were treated with sofosbuvir-based regimen—the only DAA available for all genotypes. Purpose of the study was assessing real-world data of treatment outcome among patients with HCV GEN3 and advanced liver fibrosis with sofosbuvir-based regimens.

Results

Totally 1525 genotype 3 patients were eligible for analysis; most (72.6%) were aged > 45 years, majority were males (95.1%), and all (100%) had advanced liver disease (F3 or F4 by METAVIR score based on elastography). Of those who received sofosbuvir/ribavirin (SOF/RBV) for 24 weeks, 79.3% achieved SVR, while 96.5% who received sofosbuvir/pegylated interferon/ribavirin (SOF/PEG/RBV) for 12 weeks achieved SVR (p < 0.01). Among patients with liver cirrhosis (defined as F4) overall cure rate was 85.7% as opposed to 96.4% for those with F3. Females were more likely to be cured (98.7% vs 89.7%; OR = 8.54). Patients aged 31–45 years had higher likelihood of achieving SVR compared to patients aged 46-60 years (95.7% vs 87.4%; OR = 0.32,). Independent predictors of SVR were treatment with SOF/PEG/RBV (aOR = 6.72) and lower fibrosis stage (F3) (aOR = 4.18). Real-world experience among HCV GEN3 patients with advanced liver fibrosis and treated by sofosbuvir regimen w/o PEGIFN, demonstrated overall high SVR rate.

Effect of treatment with direct antiviral agents (DAAs) on glycemic control in patients with type 2 diabetes mellitus & hepatitis C virus genotype 4

BACKGROUND AND AIMS

It is widely recognized that chronic hepatitis C is a metabolic disease that is strongly associated with type 2 diabetes mellitus (T2DM) and insulin resistance (IR). The evidence behind the effect of Direct Anti-Viral Agents (DAAs) therapy on T2DM is conflicting. The aim of the present study was to evaluate the effect of treatment with DAAs on glycemic control in patients with type-2 diabetes mellitus and chronic hepatitis C virus genotype 4.

METHODS

This study was a prospective study that conducted on 100 patients with chronic hepatitis C and Type-2 diabetes mellitus, selected from Kafr El-Sheikh Liver Research Center treated with Direct Anti-Viral Agents (DAAs) during the period from September 1, 2017 to last of August 2018. All patients in the study were subjected to the following: Full history taking stressing on the age, gender, previous treatment; clinical examination and laboratory investigations. HBA1C was assessed before and after DAAs treatment.

RESULTS

In the present study, there was a significant decrease of baseline fasting blood glucose levels after treatment when compared with before treatment. Also, there was a significant decrease of 2 h post prandial blood glucose after treatment when compared with before treatment. There was significant decrease of HBA1c levels after treatment when compared with before treatment.

CONCLUSIONS

DAAs treatment significantly improved the fasting blood glucose and help better glycemic control. This study augments the importance and the benefits of new Direct Anti-Viral Agents interferon free regimens in diabetic HCV infected patients.

Cost-effectiveness of second-generation direct-acting antiviral agents in chronic HCV infection: a systematic literature review

BACKGROUND

Our objectives were to review the economic modelling methods and cost-effectiveness of second-generation direct-acting antiviral agents for the treatment of chronic HCV infection.

METHODS

A systematic literature search was performed in February 2017 using Scopus and OVID to review relevant publications between 2011 to present. Two independent reviewers screened potential papers.

RESULTS

The database search resulted in a total of 1,536 articles; after deduplication, title/abstract and full text screening, 67 studies were included for qualitative analysis. The vast majority of studies were conducted in high-income countries (n=59) and used Markov-based modelling techniques (n=60). Most of the analyses utilized long-term time horizons; 58 studies calculated lifetime costs and outcomes. The examined treatments were heterogenic among the studies; seven analyses did not directly evaluate treatments (just with screening or genotype testing). The examined treatments (n=60) were either dominant (23%), or cost-effective at base case (57%) or in given subgroups (18%). Only one (2%) study reported that the assessed treatment was not cost-effective with the given setting and price.

CONCLUSIONS

Despite their high initial therapeutic costs, second-generation direct-acting antiviral agents were found to be cost-effective to treat chronic HCV infection. Studies were predominantly conducted in higher income countries, although we have limited information on cost-effectiveness in low- and middle-income countries, where assessment of cost-effectiveness is even more essential due to more limited health-care resources and potentially higher public health burden due to unsafe medical interventions.

Dissection of two drug-targeted regions of Hepatitis C virus subtype 4a infecting Egyptian patients

Recently, treatment of HCV infection has been improved after the development of direct acting antivirals (DAAs) which target different viral proteins (NS3-4A, NS5A and NS5B). The activity and effectiveness of these DAAs are affected by the presence of resistance associated substitutions (RASs). This study aimed to characterize HCV genotypes circulating among Egyptian HCV patients, to dissect the full sequences of HCV NS3-4A and NS5B regions, and to characterize RASs associated with NS3-4A and NS5B inhibitors in HCV treatment-naïve patients. Genotyping of 80 HCV samples from treatment-naïve patients was done using restriction fragment length polymorphism and phylogenetic analysis based on some full NS5B sequences. Results showed the prevalence of HCV subtype 4a. Twenty four new full sequences of NS3-4A and NS5B regions of subtype 4a were deposited in the GenBank database. In general, the substitutions associated with NS3-4A-targeting drugs were absent predicting possible responsiveness of Egyptian HCV patients to these drugs. In addition, the absence of amino acid substitutions associated with resistance to Sofosbuvir may predict good response to treatment with Sofosbuvir. Some amino acid substitutions associated with resistance to different classes of non-nucleoside inhibitors were detected. Further investigations on treated Egyptian HCV patients may evaluate the effectiveness of the massively used drugs. Many predicted T-cell-binding epitopes in NS3-4A and NS5B regions were found to be highly conserved in the currently studied isolates; a finding that might be important for HCV vaccine development. We demonstrated potential NS3 epitopes that could be used in engineering T cells against HCV epitopes.