Global epidemiology and genotype distribution of the hepatitis C virus infection

Antiretroviral Use in the CEASE Cohort Study and Implications for Direct-Acting Antiviral Therapy in Human Immunodeficiency Virus/Hepatitis C Virus Coinfection

Background.  Interferon-free direct-acting antiviral (DAA) regimens for hepatitis C virus (HCV) provide a major advance in clinical management, including in human immunodeficiency virus (HIV)/HCV coinfection. Drug-drug interactions (DDIs) with combination antiretroviral therapy (cART) require consideration. This study aimed to characterize the cART regimens in HIV/HCV-coinfected individuals and assess the clinical significance of DDIs with DAAs in a real-world cohort. Methods.  This analysis included participants enrolled in CEASE-D, a prospective cohort of HIV/HCV-coinfected individuals in Sydney, Australia, between July 2014 and December 2015. A simulation of potential DDIs between participants' cART and interferon-free DAA regimens was performed using www.hep-druginteractions.org and relevant prescribing information. Results.  In individuals on cART with HCV genotype (GT) 1 and 4 (n = 128), category 3 DDIs (contraindicated or not recommended) were noted in 0% with sofosbuvir/ledipasvir, 0% with sofosbuvir plus daclatasvir, 17% with sofosbuvir/velpatasvir, 36% with ombitasvir/paritaprevir/ritonavir ± dasabuvir, 51% with grazoprevir/elbasvir, and 51% with sofosbuvir plus simeprevir; current cART regimens were suitable for coadministration in 100%, 100%, 73%, 64%, 49%, and 49%, respectively. In individuals with HCV GT 2 or 3 (n = 53), category 3 DDIs were evident in 0% with sofosbuvir plus daclatasvir, 0% with sofosbuvir and ribavirin, and 13% with sofosbuvir/velpatasvir; current cART regimens were suitable in 100%, 100%, and 81%, respectively. Conclusions.  Potential DDIs are expected and will impact on DAA prescribing in HIV/HCV coinfection. Sofosbuvir in combination with an NS5A inhibitor or ribavirin appeared to be the most suitable regimens in this cohort. Evaluation of potential DDIs is required to prevent adverse events or treatment failure.

Hepatitis C virus seroprevalence in adults in Africa: a systematic review and meta-analysis

With the introduction of more efficient treatments for hepatitis C virus (HCV), improved epidemiological information is required at the country level to allow evidence-based policymaking for elaboration of national strategies and HCV resources planning. We present a systematic review with meta-analysis of HCV seroprevalence data in adults in African countries. We conducted a systematic review of all HCV seroprevalence estimates reported in African countries from 2000 to 2014 in MEDLINE, AJOL and grey literature. We assessed studies performed in the general population and among blood donors, pregnant women and HIV-positive patients. A meta-regression analysis was used to provide adjusted estimates of HCV seroprevalence in the general adult population in each country, accounting for the heterogeneity in sample age structure and population types in the included studies. We identified 775 national-level estimations, among which 184 were included. Estimates of HCV seroprevalence were produced for 38 countries, in addition to the results from nationwide representative surveys available in Egypt and Libya. Next to Egypt, which clearly stands out, the highest levels of seroprevalence were found in Middle Africa (e.g. Cameroon, Gabon and Angola) and some West African countries (e.g. Burkina Faso, Benin), and the largest absolute numbers of infected adults were found in Nigeria, Ethiopia and Democratic Republic of Congo. This study exposes the diversity of HCV epidemiology among African countries. Egypt and several countries of West and Middle Africa present a HCV burden that will require strong governmental commitment to promote efficient preventive and curative interventions.

Performance of the New Aptima HCV Quant Dx Assay in Comparison to the Cobas TaqMan HCV2 Test for Use with the High Pure System in Detection and Quantification of Hepatitis C Virus RNA in Plasma or Serum

Quantitating the level of hepatitis C virus (HCV) RNA is the standard of care for monitoring HCV-infected patients during treatment. The performances of commercially available assays differ for precision, limit of detection, and limit of quantitation (LOQ). Here, we compare the performance of the Hologic Aptima HCV Quant Dx assay (Aptima) to that of the Roche Cobas TaqMan HCV test, version 2.0, using the High Pure system (HPS/CTM), considered a reference assay since it has been used in trials defining clinical decision points in patient care. The assays' performance characteristics were assessed using HCV RNA reference panels and plasma/serum from chronically HCV-infected patients. The agreement between the assays for the 3 reference panels was good, with a difference in quantitation values of <0.5 log. High concordance was demonstrated between the assays for 245 clinical samples (kappa = 0.80; 95% confidence interval [CI], 0.720 to 0.881); however, Aptima detected and/or quantitated 20 samples that HPS/CTM did not detect, while Aptima did not detect 1 sample that was quantitated by HPS/CTM. For the 165 samples quantitated by both assays, the values were highly correlated (R= 0.98;P< 0.0001). The linearity of quantitation from concentrations of 1.4 to 6 log was excellent for both assays for all HCV genotypes (GT) tested (GT 1a, 1b, 2b, and 3a) (R(2)> 0.99). The assays had similar levels of total and intra-assay variability across all genotypes at concentrations from 1,000 to 25 IU/ml. Aptima had a greater analytical sensitivity, quantitating more than 50% of replicates at 25-IU/ml target. Aptima showed performance characteristics comparable to those of HPS/CTM and increased sensitivity, making it suitable for use as a clinical diagnostic tool on the fully automated Panther platform.

Toward a simple risk assessment screening tool for HCV infection in Egypt

Asymptomatic patients with HCV infection identified through screening program could benefit not only from treatment but also from other interventions such as counseling to maintain health and avoid risk behaviors. This might prevent the spread of infection and result in significant public health benefits. However, mass screening would quickly deplete resources. This work aims to develop a brief HCV risk assessment questionnaire that inquires initially about a wide range of risk factors found to be potentially associated with HCV infection in order to identify the few most significant questions that could be quickly used to facilitate cost-effective HCV case-finding in the general population in Egypt. An exhaustive literature search was done to include all reported HCV risk factors that were pooled in a 65 item questionnaire. After an initial pilot study, a case-control study was performed that included 1,024 cases and 1,046 controls. In a multivariable model, a list of independent risk factors were found to be significant predictors for being HCV seropositive among two age strata (<45 and >45 years) for each gender. A simplified model that assigned values of the odds ratio as a weight for each factor present predicted HCV infection with high diagnostic accuracy. Attaining the defined cut-off value of the total risk score enhances the effectiveness of screening. HCV risk factors in the Egyptian population vary by age and gender. An accurate prediction screening tool can be used to identify those at high risk who may benefit most from HCV serologic testing. These results are to be further validated in a large scale cross-sectional study to assess the wider use of this tool. J. Med. Virol. 88:1767-1775, 2016. © 2016 Wiley Periodicals, Inc.

A Predictive Model for Selecting Patients with HCV Genotype 3 Chronic Infection with a High Probability of Sustained Virological Response to Peginterferon Alfa-2a/Ribavirin

Background

Access to direct-acting antiviral agents (DAAs) is restricted in some settings; thus, the European Association for the Study of the Liver recommends dual peginterferon/ribavirin (PegIFN/RBV) therapy wherever DAAs are unavailable. HCV genotype (GT) 3 infection is now the most difficult genotype to eradicate and PegIFN/RBV remains an effective option. The goal of this study was to devise a simple predictive score to identify GT3 patients with a high probability of achieving a sustained virologic response (SVR) with PegIFN alfa-2a/RBV therapy.

Methods

Relationships between baseline characteristics and SVR were explored by multiple logistic regression models and used to develop a simple scoring system to predict SVR using data from 1239 treatment-naive GT3 patients who received PegIFN alfa-2a/RBV for 24 weeks in two large observational cohort studies.

Results

The score was validated using a database of 473 patients. Scores were assigned for six factors as follows: age (years) (≤40: 2 points; >40 but ≤55: 1); bodyweight (kg) (<70: 2; ≥70 but <90: 1); no cirrhosis/transition to cirrhosis (2); ALT ≤2.5 x ULN (1); platelets (10⁹/L) (>200: 2; ≥100 but <200: 1); HCV RNA (<400,000 IU/mL: 1). The points are summed to arrive at a score ranging from 0‒10 where higher scores indicate higher chances of SVR; 141, 123, 203, 249, 232, and 218 patients had total scores of 0‒4, 5, 6, 7, 8, and 9–10, respectively, among whom SVR rates were 45%, 62%, 72%, 76%, 84%, and 89%. Among 622 patients who had scores of 6‒10 and HCV RNA <50 IU/mL by treatment week 4 the SVR rate was 86% (532/622).

Conclusions

A simple baseline scoring system involving age, bodyweight, cirrhosis status, ALT level, platelet count and HCV RNA level can be used to identify treatment-naive Caucasian patients with HCV GT3 infection with a high probability of SVR with PegIFN alfa-2a/RBV therapy.

Recent advances in managing chronic HCV infection: focus on therapy in patients with severe liver disease

Chronic hepatitis C virus (HCV) infection still represents a major public health problem, as it is thought to be responsible for more than 350,000 deaths around the globe on a yearly basis. Fortunately, successful eradication of the virus has been associated with improved clinical outcome and reduced mortality rates. In the past few years, treatment has improved considerably by the implementation of direct-acting antivirals (DAAs). From 2014 onwards, sofosbuvir, simeprevir, daclatasvir, ledipasvir, paritaprevir, ombitasvir, and dasabuvir have been approved by the US Food and Drug Administration (FDA) and European Medicines Agency (EMA). Regimens with various combinations of these new drugs, without the use of interferon (IFN), proved to be very effective and well tolerated, even among patients with advanced liver disease. Moreover, treatment duration could be shortened to 12 weeks in the majority of patients. The high costs of these DAAs, however, limit the availability of IFN-free therapy worldwide. Even in wealthy countries, it is deemed necessary to prioritize DAA treatment in order to limit the immediate impact on the health budget. As patients with advanced liver disease are in most need of HCV clearance, many countries decided to treat those patients first. In the current review, we focus on the currently available IFN-free treatment options for patients with cirrhosis. We discuss the virological efficacy as well as the clinical relevance of these regimens among this specific patient population.

A Protease Inhibitor with Induction Therapy with Natural Interferon-β in Patients with HCV Genotype 1b Infection

The restoration of innate immune responses has potential as a novel therapeutic strategy for chronic hepatitis C (CHC). We compared the efficacy and safety of induction therapy (IT) with natural interferon-β (n-IFN-β) followed by pegylated-IFN-α/ribavirin (PR) alone (group A, n = 30) and IT with a protease inhibitor (PI) (simeprevir or vaniprevir)/PR (group B, n = 13) in CHC patients with genotype 1b and high viral loads. During IT with nIFN-β, virologic response rates in group A and group B were 10% and 8% (p = 0.6792) at week 4, 30% and 16% (p = 0.6989) at week 12 and 47% and 20% (p = 0.0887) at week 24 respectively. During and after the treatment with PR alone or PI/PR, virologic response rates in groups A and B were 50% and 82% (p = 0.01535) at week 4, 53% and 91% (p = 0.006745) at week 8, 57% and 91% (p = 0.001126) at week 12, 57% and 100% (p < 0.001845) at the end of the treatment and 57% and 80% (p < 0.005166) after treatment cessation. IT with PI/PR linked to the restoration of innate immune response was tolerated well, overcame virological breakthrough, enhanced early virologic responses, and resulted in a sustained virologic response in difficult-to-treat CHC patients. IT with PI/PR is beneficial for treating difficult-to-treat CHC patients.

Relative Importance of Hepatitis B and C Viruses in Hepatocellular Carcinoma in EMRO Countries and the Middle East: A Systematic Review

CONTEXT

Hepatocellular carcinoma (HCC) is the second most common cancer-related death worldwide. Although many factors including dietary aflatoxin B1 (AFB1) and alcoholic and non-alcoholic fatty liver diseases can lead to HCC, globally most HCC cases are due to hepatitis B virus (HBV) and hepatitis C virus (HCV). Considering the importance of these viral factors in most HCC cases and relative lack of literature from eastern Mediterranean region office of world health organization (EMRO) countries and the Middle East, we decided to perform this systematic review to find distribution of viral etiology of HCC in these regions.

EVIDENCE ACQUISITION

In this systemic review, we included all studies from 1 January 1989 to 1 September 2015 with at least 20 samples that measured HBV surface antigen (HBsAg) and antibodies to HCV (anti-HCV). The authors searched MEDLINE, Embase, Popline, Web of Science and WHO indexed databases. We searched the following MeSH terms; hepatocellular carcinoma, hepatitis B virus and hepatitis C virus or hepacvirus. Only studies using second- and third-generation HCV assays were included. Only articles studying HCC patients from EMRO countries and the Middle East were analyzed. Duplicate results that reported the same cases more than once were found and omitted. Studies in English and Farsi were reviewed. If the study was eligible, we recorded the following data; the first author, publication year and journal, study population and number and percentage of patients with different serologic statuses.

RESULTS

We found 44 studies from 12 countries in EMRO and the Middle East. HCC cases from Iran, Lebanon, Turkey and Yemen were mainly due to HBV, while those of North African nations (Egypt, Tunisia, Morocco, Algeria and Somalia) in addition to Saudi Arabia and Pakistan were mostly HCV related. Sudan showed a high seronegativity and HBV infection in its HCC cases. Unfortunately, some countries from EMRO and the Middle East did not have eligible studies.

CONCLUSIONS

HBV and HCV are important culprits of HCC in EMRO countries and the Middle East and different nations need different strategies to tackle them accordingly. Countries with high rates of HBV such as Turkey should continue their HBV vaccination and also increase sanitation. Nations with high HCV rates such as Egypt should maintain their blood product monitoring in addition to increased sanitation, especially regarding injection drug users (IDU).

Impact of eradicating hepatitis C virus on the work productivity of chronic hepatitis C (CH-C) patients: an economic model from five European countries

CH-C negatively affects work productivity (WP), creating a large economic burden. The aim of this study was to model the impact of sustained virologic response (SVR) on WP in CHC genotype 1 (GT1) patients in five European countries (EU5). Work Productivity and Activity Index-Specific Health Problem questionnaire was administered to patients across the ION clinical trials (n = 629 European patients). The analysis modelled a population of GT1 CHC patients over one year, who had been either not treated or treated with LDV/SOF. Sensitivity analyses assessed the possibility that CHC patients' labour costs were lower than the general population's and presented results by fibrosis stage. Before initiation of treatment, EU patients with CHC GT1 exhibited absenteeism and presenteeism impairments of 3.54% and 9.12%, respectively. About 91.8% of EU patients in the ION trials achieved SVR and improved absenteeism and presenteeism impairments by 16.3% and 19.5%, respectively. Monetizing these data, treatment with LDV/SOF resulted in an annual productivity gain of €435 million and a weighted average per-employed patient (PEP) gain of €900 in the EU5. PEP gains from treatment are projected to be higher in cirrhotic than in noncirrhotic patients. If CHC patients are assumed to earn 20% less than the general population, gains of €348 million (€720 PEP) annually are projected. CHC results in a significant economic burden to European society. Due to improvements in WP, SVR with treatment could provide substantial economic gains, partly offsetting the direct costs related to its widespread use.

Identification of hepatitis C virus genotype 3 by a commercial assay challenged by natural polymorphisms detected in Spain from patients with diverse origins

BACKGROUND

Hepatitis C virus (HCV) genotyping is crucial in clinical practise for determining the type and duration of antiviral therapy. Between 2009 and 2014, 24 (7.95%) of all HCV genotype 3 (HCV-3) cases obtained indeterminate results via the RealTime HCV Genotype II assay (Abbott) at a tertiary care center in Spain. HCV-3 is the second most common genotype worldwide. Moreover, it has been associated with a higher risk of liver disease progression and a lower response to the latest antivirals.

OBJECTIVE

Given the clinical significance of accurately identifying HCV-3, we aimed to characterize the genetic diversity of the HCV 5' untranslated region (5' UTR), the target of genotyping assays, by ultradeep pyrosequencing (UDPS).

STUDY DESIGN

For the 24 indeterminate samples, the 5' UTR-core was amplified and subjected to UDPS with the 454/GS-Junior platform (Roche). The genotype/subtype of each identified haplotype was assigned by phylogenetic analysis. For comparison, three additional samples correctly identified as HCV-3 by the real-time assay were also analyzed.

RESULTS

HCV genotyping based on 5' UTR-core UDPS was in agreement with NS5B Sanger sequencing in all cases, confirming the absence of mixed infections and recombination events. The generated 5' UTR sequences proved the presence of one to three polymorphisms at the probe-binding site of the Abbott assay, thereby differentiating indeterminate from correctly genotyped HCV-3 samples.

CONCLUSIONS

The observed naturally occurring polymorphisms provide insight into regional differences observed with genotype 3, their impact on genotyping assay performance, and potential improvement and designing options.

Hepatitis C Virus Epidemiology in Djibouti, Somalia, Sudan, and Yemen: Systematic Review and Meta-Analysis

OBJECTIVES

To characterize hepatitis C virus (HCV) epidemiology and assess country-specific population-level HCV prevalence in four countries in the Middle East and North Africa (MENA) region: Djibouti, Somalia, Sudan, and Yemen.

METHODS

Reports of HCV prevalence were systematically reviewed as per PRISMA guidelines. Pooled HCV prevalence estimates in different risk populations were conducted when the number of measures per risk category was at least five.

RESULTS

We identified 101 prevalence estimates. Pooled HCV antibody prevalence in the general population in Somalia, Sudan and Yemen was 0.9% (95% confidence interval [95%CI]: 0.3%-1.9%), 1.0% (95%CI: 0.3%-1.9%) and 1.9% (95%CI: 1.4%-2.6%), respectively. The only general population study from Djibouti reported a prevalence of 0.3% (CI: 0.2%-0.4%) in blood donors. In high-risk populations (e.g., haemodialysis and haemophilia patients), pooled HCV prevalence was 17.3% (95%CI: 8.6%-28.2%) in Sudan. In Yemen, three studies of haemodialysis patients reported HCV prevalence between 40.0%-62.7%. In intermediate-risk populations (e.g.. healthcare workers, in patients and men who have sex with men), pooled HCV prevalence was 1.7% (95%CI: 0.0%-4.9%) in Somalia and 0.6% (95%CI: 0.4%-0.8%) in Sudan.

CONCLUSION

National HCV prevalence in Yemen appears to be higher than in Djibouti, Somalia, and Sudan as well as most other MENA countries; but otherwise prevalence levels in this subregion are comparable to global levels. The high HCV prevalence in patients who have undergone clinical care appears to reflect ongoing transmission in clinical settings. HCV prevalence in people who inject drugs remains unknown.

Hepatitis C Virus Epidemiology in Djibouti, Somalia, Sudan, and Yemen: Systematic Review and Meta-Analysis

OBJECTIVES

To characterize hepatitis C virus (HCV) epidemiology and assess country-specific population-level HCV prevalence in four countries in the Middle East and North Africa (MENA) region: Djibouti, Somalia, Sudan, and Yemen.

METHODS

Reports of HCV prevalence were systematically reviewed as per PRISMA guidelines. Pooled HCV prevalence estimates in different risk populations were conducted when the number of measures per risk category was at least five.

RESULTS

We identified 101 prevalence estimates. Pooled HCV antibody prevalence in the general population in Somalia, Sudan and Yemen was 0.9% (95% confidence interval [95%CI]: 0.3%-1.9%), 1.0% (95%CI: 0.3%-1.9%) and 1.9% (95%CI: 1.4%-2.6%), respectively. The only general population study from Djibouti reported a prevalence of 0.3% (CI: 0.2%-0.4%) in blood donors. In high-risk populations (e.g., haemodialysis and haemophilia patients), pooled HCV prevalence was 17.3% (95%CI: 8.6%-28.2%) in Sudan. In Yemen, three studies of haemodialysis patients reported HCV prevalence between 40.0%-62.7%. In intermediate-risk populations (e.g.. healthcare workers, in patients and men who have sex with men), pooled HCV prevalence was 1.7% (95%CI: 0.0%-4.9%) in Somalia and 0.6% (95%CI: 0.4%-0.8%) in Sudan.

CONCLUSION

National HCV prevalence in Yemen appears to be higher than in Djibouti, Somalia, and Sudan as well as most other MENA countries; but otherwise prevalence levels in this subregion are comparable to global levels. The high HCV prevalence in patients who have undergone clinical care appears to reflect ongoing transmission in clinical settings. HCV prevalence in people who inject drugs remains unknown.

Hepatitis C Virus Epidemiology in Djibouti, Somalia, Sudan, and Yemen: Systematic Review and Meta-Analysis

OBJECTIVES

To characterize hepatitis C virus (HCV) epidemiology and assess country-specific population-level HCV prevalence in four countries in the Middle East and North Africa (MENA) region: Djibouti, Somalia, Sudan, and Yemen.

METHODS

Reports of HCV prevalence were systematically reviewed as per PRISMA guidelines. Pooled HCV prevalence estimates in different risk populations were conducted when the number of measures per risk category was at least five.

RESULTS

We identified 101 prevalence estimates. Pooled HCV antibody prevalence in the general population in Somalia, Sudan and Yemen was 0.9% (95% confidence interval [95%CI]: 0.3%-1.9%), 1.0% (95%CI: 0.3%-1.9%) and 1.9% (95%CI: 1.4%-2.6%), respectively. The only general population study from Djibouti reported a prevalence of 0.3% (CI: 0.2%-0.4%) in blood donors. In high-risk populations (e.g., haemodialysis and haemophilia patients), pooled HCV prevalence was 17.3% (95%CI: 8.6%-28.2%) in Sudan. In Yemen, three studies of haemodialysis patients reported HCV prevalence between 40.0%-62.7%. In intermediate-risk populations (e.g.. healthcare workers, in patients and men who have sex with men), pooled HCV prevalence was 1.7% (95%CI: 0.0%-4.9%) in Somalia and 0.6% (95%CI: 0.4%-0.8%) in Sudan.

CONCLUSION

National HCV prevalence in Yemen appears to be higher than in Djibouti, Somalia, and Sudan as well as most other MENA countries; but otherwise prevalence levels in this subregion are comparable to global levels. The high HCV prevalence in patients who have undergone clinical care appears to reflect ongoing transmission in clinical settings. HCV prevalence in people who inject drugs remains unknown.

Analysis of HCV-6 isolates among Asian-born immigrants in North America reveals their high genetic diversity and a new subtype

We characterized full-length genomes for 15 HCV-6 isolates, all from Asian immigrants living in North America. Among these isolates, nine were novel variants showing >15% nucleotide differences from their nearest relatives, representing lineages distinct from known subtypes. The other six were classified into subtypes 6c, 6h, 6q, 6r, and 6s. The partial sequences were also determined for five additional HCV-6 isolates, three from the US and two from Canada. The latter two were assigned to new subtype 6xf as they were found to classify with two other isolates for which we recently reported their full-length genomes. We further analyzed partial Core-E1 sequences of 100 HCV-6 isolates sampled in North America, seven from the US and 93 from Canada and all from Asian immigrants except for four from Caucasians. These 100 isolates belonged to 20 assigned subtypes and 16 unclassified lineages showing great genetic diversity and enhanced significance to public health.

Decreasing Hepatitis C Virus Infection in Thailand in the Past Decade: Evidence from the 2014 National Survey

Hepatitis C virus (HCV) infection affects ≥ 180 million individuals worldwide especially those living in developing countries. Recent advances in direct-acting therapeutics promise effective treatments for chronic HCV carriers, but only if the affected individuals are identified. Good treatment coverage therefore requires accurate epidemiological data on HCV infection. In 2014, we determined the current prevalence of HCV in Thailand to assess whether over the past decade the significant number of chronic carriers had changed. In total, 5964 serum samples from Thai residents between 6 months and 71 years of age were obtained from 7 provinces representing all 4 geographical regions of Thailand and screened for the anti-HCV antibody. Positive samples were further analyzed using RT-PCR, sequencing, and phylogenetic analysis to identify the prevailing HCV genotypes. We found that 56 (0.94%) samples tested positive for anti-HCV antibody (mean age = 36.6±17.6 years), while HCV RNA of the core and NS5B subgenomic regions was detected in 23 (41%) and 19 (34%) of the samples, respectively. The seropositive rates appeared to increase with age and peaked in individuals 41–50 years old. These results suggested that approximately 759,000 individuals are currently anti-HCV-positive and that 357,000 individuals have viremic HCV infection. These numbers represent a significant decline in the prevalence of HCV infection. Interestingly, the frequency of genotype 6 variants increased from 8.9% to 34.8%, while the prevalence of genotype 1b declined from 27% to 13%. These most recent comprehensive estimates of HCV burden in Thailand are valuable towards evidence-based treatment coverage for specific population groups, appropriate allocation of resources, and improvement in the national public health policy.

Applicability of Hepatitis C Virus RNA Viral Load Thresholds for 8-Week Treatments in Patients With Chronic Hepatitis C Virus Genotype 1 Infection

BACKGROUND

Interferon-free treatment of chronic hepatitis C virus (HCV) genotype 1 infection may be shortened to 8 weeks in treatment-naive, noncirrhotic patients with baseline HCV RNA levels of <4 or <6 million (M) IU/mL based on post-hoc analyses of phase 3 trial data. The applicability of these viral load thresholds in clinical practice is unknown.

METHODS

Pretreatment and on-treatment serum samples (n = 740) from patients with HCV genotype 1 infection were included for HCV RNA analysis with 2 widely used assays, Cobas AmpliPrep/CobasTaqMan (CAP/CTM) and Abbott RealTime HCV (ART) assays.

RESULTS

HCV RNA levels were significantly higher with CAP/CTM than with ART (overall difference, +0.11 log10 IU/mL; P < .001). In treatment-naive, noncirrhotic patients, discordance rates around the clinical cutoffs at 4M and 6M IU/mL were 23% and 18%, respectively. The mean differences between assays in discordant samples were 0.38 (4M) and 0.41 (6M) log10 IU/mL, respectively. Overall, 87% and 95% of treatment-naive, noncirrhotic patients, respectively, had baseline HCV RNA levels below 4M and 6M IU/mL with ART. These rates were significantly higher than those measured with CAP/CTM (64% and 78%, respectively; P < .001). Finally, discordance rates around the proposed thresholds in 2 consecutive samples of the same patient were in the range of 1%-2% for ART and 13%-17% for CAP/CTM.

CONCLUSIONS

Selection of patients for 8-week regimens on the basis of a single HCV RNA determination may not be reliable because viral load levels around the proposed clinical thresholds show significant interassay and intrapatient variability.

New prospects for the treatment and prevention of hepatitis C in children

PURPOSE OF REVIEW

Combined pegylated interferon-α and ribavirin remains the standard therapy for pediatric hepatitis C virus (HCV) infections in 2016, but direct-acting antivirals (DAAs) with greatly improved efficacy and safety are now approved for adults. Here we review the major classes of DAAs and their anticipated use for treatment and potentially prevention of HCV in children.

RECENT FINDINGS

Currently approved DAAs target the viral protease, polymerase, and NS5A, a protein involved in viral replication and assembly. In combination, DAAs have lifted sustained virologic response rates in adults to more than 90% for multiple HCV genotypes, and the rich DAA pipeline promises further improvements. Clinical trials of interferon-free DAA regimens have been initiated for children ages 3-17 years. In 2016, the first efficacy trial of a preventive HCV vaccine is also underway. While awaiting a vaccine, there is hope that increased DAA utilization may prevent pediatric HCV infections by shrinking the pool of infectious persons.

SUMMARY

Interferon-free DAA regimens have revolutionized therapy for HCV-infected adults and, pending results of pediatric trials, will likely do the same for HCV-infected children. If widely deployed, DAA therapies may also help to reduce the number of new vertically and horizontally acquired pediatric infections.

The importance of resistance to direct antiviral drugs in HCV infection in clinical practice

Treatment of chronic hepatitis C virus (HCV) infection with direct-acting antiviral agents (DAA) is associated with high rates of sustained virologic response. Remaining factors associated with treatment failure include advanced stages of liver fibrosis, response to previous antiviral therapy and viral factors such as baseline viral load and suboptimal interaction of the DAA with the target based on viral variants. Heterogeneity within NS3, NS5A, and NS5B areas interacting with DAAs exist between HCV geno- and subtypes as well as HCV isolates of the same geno- and subtype and amino acid polymorphisms associated with suboptimal efficacy of DAAs are termed resistance-associated variants (RAVs). RAVs may be associated with virologic treatment failure. However, virologic treatment failure typically occurs only if other negative predictive host or viral factors are present at the same time, susceptibility to additional antiviral agents is reduced or duration of treatment is suboptimal. In this review geno- and phenotypic resistance testing as well as clinical data on the importance of RAVs for conventional triple therapies with sofosbuvir, simeprevir, and daclatasvir and available interferon-free DAA combinations are discussed.

New approaches in the treatment of hepatitis C

About 130-170 million people, is estimated to be infected with the hepatitis C virus (HCV). Chronic HCV infection is one of the leading causes of liver-related death and in many countries it is the primary reason for having a liver transplant. The main aim of antiviral treatment is to eradicate the virus. Until a few years ago the only treatment strategy was based on the combination of pegylated interferon and ribavirin (PEG/RBV). However, in genotypes 1 and 4 the rates of viral response did not surpass 50%, reaching up to 80% in the rest. In 2011 approval was given for the first direct acting antiviral agents (DAA), boceprevir and telaprevir, for treatment of genotype 1, in combination with traditional dual therapy. This strategy managed to increase the rates of sustained viral response (SVR) in both naive patients and in retreated patients, but with greater toxicity, interactions and cost, as well as being less safe in patients with advanced disease, in whom this treatment can trigger decompensation or even death. The recent, accelerated incorporation since 2013 of new more effective DAA, with pan-genomic properties and excellent tolerance, besides increasing the rates of SVR (even up to 100%), has also created a new scenario: shorter therapies, less toxicity and regimens free of PEG/RBV. This has enabled their almost generalised applicability in all patients. However, it should be noted that most of the scientific evidence available is based on expert opinion, case-control series, cohort studies and phase 2 and 3 trials, some with a reduced number of patients and select groups. Few data are currently available about the use of these drugs in daily clinical practice, particularly in relation to the appearance of side effects and interactions with other drugs, or their use in special populations or persons with the less common genotypes. This situation suggests the need for the generalised implementation of registries of patients receiving antiviral therapy. The main inconvenience of these new drugs is their high cost. This necessitates selection and prioritization of candidate patients to receive them, via strategies established by the various national organs, in accordance with the recommendations of scientific societies.

Vertically acquired hepatitis C virus infection: Correlates of transmission and disease progression

The worldwide prevalence of hepatitis C virus (HCV) infection in children is 0.05%-0.4% in developed countries and 2%-5% in resource-limited settings, where inadequately tested blood products or un-sterile medical injections still remain important routes of infection. After the screening of blood donors, mother-to-child transmission (MTCT) of HCV has become the leading cause of pediatric infection, at a rate of 5%. Maternal HIV co-infection is a significant risk factor for MTCT and anti-HIV therapy during pregnancy seemingly can reduce the transmission rate of both viruses. Conversely, a high maternal viral load is an important, but not preventable risk factor, because at present no anti-HCV treatment can be administered to pregnant women to block viral replication. Caution is needed in adopting obstetric procedures, such as amniocentesis or internal fetal monitoring, that can favor fetal exposure to HCV contaminated maternal blood, though evidence is lacking on the real risk of single obstetric practices. Mode of delivery and type of feeding do not represent significant risk factors for MTCT. Therefore, there is no reason to offer elective caesarean section or discourage breast-feeding to HCV infected parturients. Information on the natural history of vertical HCV infection is limited. The primary infection is asymptomatic in infants. At least one quarter of infected children shows a spontaneous viral clearance (SVC) that usually occurs within 6 years of life. IL-28B polymorphims and genotype 3 infection have been associated with greater chances of SVC. In general, HCV progression is mild or moderate in children with chronic infection who grow regularly, though cases with marked liver fibrosis or hepatic failure have been described. Non-organ specific autoantibodies and cryoglobulins are frequently found in children with chronic infection, but autoimmune diseases or HCV associated extrahepatic manifestations are rare.

Sofosbuvir treatment and hepatitis C virus infection

Hepatitis C virus (HCV) infection is a serious problem worldwide. The use of interferon-based therapy has made HCV eradication challenging. The recent appearance of direct-acting antiviral agents (DAAs) has changed HCV therapy. Combining the use of DAAs with peginterferon and ribavirin has improved treatment efficacy. Furthermore, the combination of different orally administered DAAs has enabled interferon-free therapy with much higher efficacy and safety. In particular, sofosbuvir, a nucleotide-based NS5B inhibitor, prevents HCV RNA synthesis by acting as a "chain terminator". Treatment with sofosbuvir has attained an extremely high rate of sustained virologic response. The current review summarizes the efficacy and safety of sofosbuvir therapy.

Use of Hepatitis C Virus (HCV) Immunoglobulin G Antibody Avidity as a Biomarker to Estimate the Population-Level Incidence of HCV Infection

BACKGROUND

Sensitive methods are needed to estimate the population-level incidence of hepatitis C virus (HCV) infection.

METHODS

We developed an HCV immunoglobulin G (IgG) antibody avidity assay by modifying the Ortho 3.0 HCV enzyme-linked immunoassay and tested 997 serum or plasma samples from 568 people who inject drugs enrolled in prospective cohort studies. Avidity-based testing algorithms were evaluated by their (1) mean duration of recent infection (MDRI), defined as the average time an individual is identified as having been recently infected, according to a given algorithm; (2) false-recent rate, defined as the proportion of samples collected >2 years after HCV seroconversion that were misclassified as recent; (3) sample sizes needed to estimate incidence; and (4) power to detect a reduction in incidence between serial cross-sectional surveys.

RESULTS

A multiassay algorithm (defined as an avidity index of <30%, followed by HCV viremia detection) had an MDRI of 147 days (95% confidence interval [CI], 125-195 days), and the false-recent rates were 0.7% (95% CI, .2%-1.8%) and 7.6% (95% CI, 4.2%-12.3%) among human immunodeficiency virus (HIV)-negative and HIV-positive persons, respectively. In various simulated high-risk populations, this algorithm required <1000 individuals to estimate incidence (relative standard error, 30%) and had >80% power to detect a 50% reduction in incidence.

CONCLUSIONS

Avidity-based algorithms have the capacity to accurately estimate HCV infection incidence and rapidly assess the impact of public health efforts among high-risk populations. Efforts to optimize this method should be prioritized.

Advances in the management of HIV/HCV coinfection

HCV coinfection has emerged as a major cause of non-AIDS-related morbidity and mortality in HIV-positive patients. As a consequence of the availability of modern combined antiretroviral therapy regimens, for optimally managed HIV/HCV-coinfected patients, the rates of liver fibrosis progression and the risk of liver-related events are increasingly similar to those of HCV-monoinfected patients. Moreover, our understanding of modulators of liver disease progression has greatly improved. In addition to immune status, endocrine, metabolic, genetic and viral factors are closely interrelated and might be important determinants of liver disease progression. In the last decade, a variety of serologic and radiographic tests for noninvasive liver disease staging have been extensively validated and are commonly used in HIV/HCV-coinfected patients. Sustained virologic response prevents end-stage liver disease, hepatocellular carcinoma, and death, with an even greater effect size in HIV-positive compared to HIV-negative patients. As interferon-free regimens achieve comparable rates of sustained virologic response in HIV-negative and HIV-positive patients, HIV/HCV-coinfected patients should from now on be referred to as a special, rather than a difficult-to-treat, population. Our comprehensive review covers all relevant aspects of HIV/HCV coinfection. Beginning with the changing epidemiology, it also provides new insights into the natural history of this condition and gives an overview on non-invasive techniques for the staging of liver disease. Furthermore, it outlines current recommendations for the treatment of acute hepatitis C and summarizes the unprecedented advances in the field of chronic hepatitis C therapy.

Effectiveness of needle/syringe programmes and opiate substitution therapy in preventing HCV transmission among people who inject drugs

This is the protocol for a review and there is no abstract. The objectives are as follows: To assess the impact of needle/syringe programmes with and without opiate substitution therapy (OST) on the incidence of HCV infection among people who inject drugs (PWID).To assess the effect of OST alone on the incidence of HCV infection among PWID.

RESEARCH QUESTIONS

How effective are needle/syringe programmes (NSP) with and without the use of OST for reducing HCV incidence among PWID?How effective is OST alone for reducing HCV incidence among PWID?How does the effect of NSP and OST vary according to duration of treatment (i.e. for NSPs weekly attendance versus monthly)?How does the effect of NSP vary according to the type of service (fixed site versus mobile; high coverage versus low coverage)?How does the effect of OST vary according to the dosage of OST, type of substitution used and adherence to treatment?

Mericitabine and Either Boceprevir or Telaprevir in Combination with Peginterferon Alfa-2a plus Ribavirin for Patients with Chronic Hepatitis C Genotype 1 Infection and Prior Null Response: The Randomized DYNAMO 1 and DYNAMO 2 Studies

Most patients with chronic hepatitis C virus (HCV) genotype 1 infection who have had a previous null response (<2-log10 reduction in HCV RNA by treatment week 12) to peginterferon/ribavirin (PegIFN/RBV) do not achieve a sustained virological response (SVR) when re-treated with a first-generation HCV protease inhibitor (PI) administered in combination with PegIFN/RBV. We studied the incremental benefits associated with adding mericitabine (nucleoside analog inhibitor of HCV polymerase) to PI plus PegIFN alfa-2a/RBV-based therapy in two double-blind randomized multicenter phase 2 trials (with boceprevir in DYNAMO 1, and with telaprevir in DYNAMO 2). The primary endpoint in both trials was SVR, defined as HCV RNA <25 IU/mL 12 weeks after the end of treatment (SVR12). Overall, the addition of mericitabine to PI plus PegIFN alfa-2a/RBV therapy resulted in SVR12 rates of 60-70% in DYNAMO 1 and of 71-96% in DYNAMO 2. SVR12 rates were similar in patients infected with HCV genotype 1a and 1b in both trials. The placebo control arms in both studies were stopped because of high rates of virological failure. Numerically lower relapse rates were associated with longer treatment with mericitabine (24 versus 12 weeks), telaprevir-containing regimens, and regimens that included 48 weeks of PegIFN alfa-2a/RBV therapy. No mericitabine resistance mutations were identified in any patient in either trial. The addition of mericitabine did not add to the safety burden associated with either telaprevir or boceprevir-based regimens. These studies demonstrate increased SVR rates and reduced relapse rates in difficult-to-treat patients when a nucleoside polymerase inhibitor with intermediate antiviral potency is added to regimens containing a first-generation PI.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01482403 and ClinicalTrials.gov NCT01482390.

Sofosbuvir plus ribavirin for the treatment of patients with chronic genotype 1 or 6 hepatitis C virus infection in Hong Kong

BACKGROUND

In Hong Kong, most patients with hepatitis C virus (HCV) have either genotype 6a or 1b infection.

AIM

To evaluate the efficacy and safety of sofosbuvir with ribavirin in treatment-naïve patients in Hong Kong with HCV genotype 1 or 6.

METHODS

In an open-label study, patients were randomised to sofosbuvir 400 mg once daily plus ribavirin 1000-1200 divided twice daily for 12 (n = 10), 16 (n = 11) or 24 (n = 10) weeks. The primary endpoint was the percentage of patients with HCV RNA < LLOQ (lower limit of quantification, 25 IU/mL) 12 weeks after cessation of therapy (SVR12).

RESULTS

All 31 patients (20 HCV genotype 1 and 11 genotype 6) had HCV RNA < LLOQ by Week 4 of treatment and at their last on-treatment visit. SVR12 rates were high in all treatment groups: 100% (10/10) for 12 weeks, 100% (11/11) for 16 weeks and 90% (9/10) for 24 weeks of therapy. The only patient who did not reach SVR12 had genotype 1 HCV and relapsed at post-treatment Week 4. Sofosbuvir with ribavirin was generally well tolerated. The most common adverse events were malaise (13%) and upper respiratory tract infection (13%), followed by anaemia (10%). No patients experienced serious adverse events. One patient discontinued treatment at Week 16 because of an adverse event. The event, upper respiratory tract infection, was not considered treatment related by the investigator. This subject achieved SVR12.

CONCLUSIONS

The all-oral regimen sofosbuvir plus ribavirin is effective in treatment-naïve patients in Hong Kong with genotype 1 or 6 HCV.

TRIAL REGISTRATION NUMBER

NCT02021643.

The 5th Canadian Symposium on Hepatitis C Virus: We Are Not Done Yet-Remaining Challenges in Hepatitis C

Hepatitis C virus (HCV) affects approximately 268,000 Canadians and results in more years of life lost than any other infectious disease in the country. Both the Canadian Institutes of Health Research (CIHR) and the Public Health Agency of Canada (PHAC) have identified HCV-related liver disease as a priority and supported the establishment of a National Hepatitis C Research Network. In 2015, the introduction of new interferon- (IFN-) free therapies with high cure rates (>90%) and few side effects revolutionized HCV therapy. However, a considerable proportion of the population remains undiagnosed and treatment uptake remains low in Canada due to financial, geographical, cultural, and social barriers. Comprehensive prevention strategies, including enhanced harm reduction, broader screening, widespread treatment, and vaccine development, are far from being realized. The theme of the 2016 symposium, "We're not done yet: remaining challenges in Hepatitis C," was focused on identifying strategies to enhance prevention, diagnosis, and treatment of HCV to reduce disease burden and ultimately eliminate HCV in Canada.

Interferon lambda 4 genotypes and resistance-associated variants in patients infected with hepatitis C virus genotypes 1 and 3

Single-nucleotide polymorphisms (SNPs) in the interferon lambda 4 (IFNL4) gene are predictors for treatment success in patients with hepatitis C virus (HCV) infection. For direct-acting antiviral combinations only weak association with IFNL4 SNPs was observed. Little is known about potential selections of resistance-associated variants (RAVs) by the IFNL4 genotype. This study analyzed the prevalence of RAVs to currently approved direct-acting antivirals in a large European population in correlation to SNPs in IFNL4. Samples of 633 patients chronically infected with HCV genotypes 1a (n = 259), 1b (n = 323), and 3 (n = 51) were genotyped for rs12979860 (formerly known as IL28B) and rs368234815. RAVs in NS3, NS5A, and NS5B were detected by population-based sequencing. In addition, IFNL4 SNPs and NS5A RAVs were analyzed including deep sequencing (n = 109) in an independent replication cohort of HCV genotype 1-infected patients (n = 201). No significant correlation was found between IFNL4 SNPs and rare and common RAVs within NS3 and NS5B. In contrast, the NS5A RAV Y93H was detected frequently in HCV genotype 1b (14%) and significantly associated with the beneficial IFNL4 SNPs (P < 0.001 and P = 0.002, respectively). Moreover, the presence of Y93H in HCV genotype 1b patients was significantly associated with the second site variant T83M (P < 0.001). Independent factors significantly associated with the presence of Y93H were IFNL4 genotype and high baseline viral load.

CONCLUSION

The NS5A RAV Y93H is significantly associated with the presence of beneficial IFNL4 SNPs and a high baseline viral load in HCV genotype 1-infected patients, which may explain a lack of correlation or even an inverse correlation of treatment response with IFNL4 genotype in some NS5A inhibitor containing IFN-free regimens.

Efficacy and Safety of Ribavirin with Sofosbuvir Plus Ledipasvir in Patients with Genotype 1 Hepatitis C: A Meta-Analysis

BACKGROUND

Sofosbuvir and ledipasvir with or without ribavirin (RBV) regimens (SLR vs. SL) have exhibited promising results for the treatment of patients with hepatitis C virus (HCV) genotype 1 infection.

AIM

To comprehensively compare the efficacy and safety of the SL and SLR regimen for the treatment of chronic HCV genotype 1 infections.

METHODS

The Cochrane Library, PubMed, Web of Science, and EMBASE databases were searched. Only RCTs that compared the efficacy and safety of SL or SLR regimen for the treatment of chronic HCV genotype 1 infection were included. The primary outcome measures were the sustained virological response weeks 12 (SVR12) post-treatment and adverse events (AEs).

RESULTS

Seven studies comprising 2601 patients were included. Compared with the SL regimen, SLR yielded a similar probability of having an SVR12 (RR 1.002, 95 % CI 0.998, 1.017, P = 0.780). Based on subgroup analyses, the addition of RBV to the 8-week SL regimen improved the SVR12 rate. However, the SLR regimen for 12 or 24 weeks did not show a superior SVR12 rate regardless of treatment history and the presence or absence of cirrhosis. The pooled incidence of AEs was higher in patients that received the SLR treatment regimen (RR 1.140, 95 % CI 1.095, 1.187, P = 0.000).

CONCLUSIONS

The 12-week or 24-week SL regimen with a low incidence of AEs is as effective and well tolerated as the SLR regimen for the treatment of patients with chronic HCV genotype 1 infection.

Sofosbuvir and Velpatasvir for HCV Genotype 2 and 3 Infection

BACKGROUND

In phase 2 trials, treatment with the combination of the nucleotide polymerase inhibitor sofosbuvir and the NS5A inhibitor velpatasvir resulted in high rates of sustained virologic response in patients chronically infected with hepatitis C virus (HCV) genotype 2 or 3.

METHODS

We conducted two randomized, phase 3, open-label studies involving patients who had received previous treatment for HCV genotype 2 or 3 and those who had not received such treatment, including patients with compensated cirrhosis. In one trial, patients with HCV genotype 2 were randomly assigned in a 1:1 ratio to receive sofosbuvir-velpatasvir, in a once-daily, fixed-dose combination tablet (134 patients), or sofosbuvir plus weight-based ribavirin (132 patients) for 12 weeks. In a second trial, patients with HCV genotype 3 were randomly assigned in a 1:1 ratio to receive sofosbuvir-velpatasvir for 12 weeks (277 patients) or sofosbuvir-ribavirin for 24 weeks (275 patients). The primary end point for the two trials was a sustained virologic response at 12 weeks after the end of therapy.

RESULTS

Among patients with HCV genotype 2, the rate of sustained virologic response in the sofosbuvir-velpatasvir group was 99% (95% confidence interval [CI], 96 to 100), which was superior to the rate of 94% (95% CI, 88 to 97) in the sofosbuvir-ribavirin group (P=0.02). Among patients with HCV genotype 3, the rate of sustained virologic response in the sofosbuvir-velpatasvir group was 95% (95% CI, 92 to 98), which was superior to the rate of 80% (95% CI, 75 to 85) in the sofosbuvir-ribavirin group (P<0.001). The most common adverse events in the two studies were fatigue, headache, nausea, and insomnia.

CONCLUSIONS

Among patients with HCV genotype 2 or 3 with or without previous treatment, including those with compensated cirrhosis, 12 weeks of treatment with sofosbuvir-velpatasvir resulted in rates of sustained virologic response that were superior to those with standard treatment with sofosbuvir-ribavirin. (Funded by Gilead Sciences; ASTRAL-2 ClinicalTrials.gov number, NCT02220998; and ASTRAL-3, NCT02201953.).

Sofosbuvir and Velpatasvir for HCV Genotype 1, 2, 4, 5, and 6 Infection

BACKGROUND

A simple treatment regimen that is effective in a broad range of patients who are chronically infected with the hepatitis C virus (HCV) remains an unmet medical need.

METHODS

We conducted a phase 3, double-blind, placebo-controlled study involving untreated and previously treated patients with chronic HCV genotype 1, 2, 4, 5, or 6 infection, including those with compensated cirrhosis. Patients with HCV genotype 1, 2, 4, or 6 were randomly assigned in a 5:1 ratio to receive the nucleotide polymerase inhibitor sofosbuvir and the NS5A inhibitor velpatasvir in a once-daily, fixed-dose combination tablet or matching placebo for 12 weeks. Because of the low prevalence of genotype 5 in the study regions, patients with genotype 5 did not undergo randomization but were assigned to the sofosbuvir-velpatasvir group. The primary end point was a sustained virologic response at 12 weeks after the end of therapy.

RESULTS

Of the 624 patients who received treatment with sofosbuvir-velpatasvir, 34% had HCV genotype 1a, 19% genotype 1b, 17% genotype 2, 19% genotype 4, 6% genotype 5, and 7% genotype 6. A total of 8% of patients were black, 19% had cirrhosis, and 32% had been previously treated for HCV. The rate of sustained virologic response among patients receiving sofosbuvir-velpatasvir was 99% (95% confidence interval, 98 to >99). Two patients receiving sofosbuvir-velpatasvir, both with HCV genotype 1, had a virologic relapse. None of the 116 patients receiving placebo had a sustained virologic response. Serious adverse events were reported in 15 patients (2%) in the sofosbuvir-velpatasvir group and none in the placebo group.

CONCLUSIONS

Once-daily sofosbuvir-velpatasvir for 12 weeks provided high rates of sustained virologic response among both previously treated and untreated patients infected with HCV genotype 1, 2, 4, 5, or 6, including those with compensated cirrhosis. (Funded by Gilead Sciences; ClinicalTrials.gov number, NCT02201940.).

Network Analysis of the Chronic Hepatitis C Virome Defines Hypervariable Region 1 Evolutionary Phenotypes in the Context of Humoral Immune Responses

Hypervariable region 1 (HVR1) of hepatitis C virus (HCV) comprises the first 27 N-terminal amino acid residues of E2. It is classically seen as the most heterogeneous region of the HCV genome. In this study, we assessed HVR1 evolution by using ultradeep pyrosequencing for a cohort of treatment-naive, chronically infected patients over a short, 16-week period. Organization of the sequence set into connected components that represented single nucleotide substitution events revealed a network dominated by highly connected, centrally positioned master sequences. HVR1 phenotypes were observed to be under strong purifying (stationary) and strong positive (antigenic drift) selection pressures, which were coincident with advancing patient age and cirrhosis of the liver. It followed that stationary viromes were dominated by a single HVR1 variant surrounded by minor variants comprised from conservative single amino acid substitution events. We present evidence to suggest that neutralization antibody efficacy was diminished for stationary-virome HVR1 variants. Our results identify the HVR1 network structure during chronic infection as the preferential dominance of a single variant within a narrow sequence space.

IMPORTANCE

HCV infection is often asymptomatic, and chronic infection is generally well established in advance of initial diagnosis and subsequent treatment. HVR1 can undergo rapid sequence evolution during acute infection, and the variant pool is typically seen to diverge away from ancestral sequences as infection progresses from the acute to the chronic phase. In this report, we describe HVR1 viromes in chronically infected patients that are defined by a dominant epitope located centrally within a narrow variant pool. Our findings suggest that weakened humoral immune activity, as a consequence of persistent chronic infection, allows for the acquisition and maintenance of host-specific adaptive mutations at HVR1 that reflect virus fitness.

Awareness of the severity of liver disease re-examined using software-combined biomarkers of liver fibrosis and necroinflammatory activity

BACKGROUND

Effective antiviral treatment (direct-acting antiviral agents (DAAs)), the requirement for a fibrosis score to support DDA reimbursement and a screening strategy, such as the USA baby boomer campaign, should lead to an increased awareness of liver disease severity.

OBJECTIVE

To compare the awareness of liver disease severity between the USA and France, two countries with similar access to hepatitis C virus (HCV) and hepatitis B virus (HBV) treatments, similar rules for treatment reimbursement and similar availability of validated fibrosis tests, but with different policies, as France has no screening.

METHOD

The global database of the FibroTest-ActiTest, including 1,085,657 subjects between 2002 and 2014, was retrospectively analysed. Awareness was defined as the test prescription rate and was compared between the USA and France, according to year of birth, gender and dates of DAA availability and screening campaign (2013-2014).

RESULTS

In the USA 252,688 subjects were investigated for HCV, with a dramatic increase (138%) in the test rate in 2013-2014 (119,271) compared with 2011-2012 (50,031). In France 470,762 subjects were investigated (subjects with HCV and other disease) and the rates were stable. In USA 82.4% of subjects and in France 84.6% were classified as either the highest or lowest priority. The most striking difference was the higher test rate in women born between 1935 and 1944 in France 30,384/200,672 (15.1%) compared with the USA 8035/97,079 (8.3%) (OR=1.98 (95% CI 1.93 to 2.03) p<0.0001). This resulted in twice as many cases of cirrhosis being detected, 2.6% (5191/200,672 women) and 1.3% (1303/97,079), respectively, despite the same prevalence of cirrhosis in this age group (17.1% vs 16.2%) and without any clear explanation as to why they had not been included in the USA screening.

CONCLUSIONS

This study highlighted in the USA the association between awareness of liver disease and both the HCV campaign and DAA availability. In comparison with France, there was a dramatically lower awareness of cirrhosis in the USA for women born between 1935 and 1944.

Impact of IL28B, APOH and ITPA Polymorphisms on Efficacy and Safety of TVR- or BOC-Based Triple Therapy in Treatment-Experienced HCV-1 Patients with Compensated Cirrhosis from the ANRS CO20-CUPIC Study

BACKGROUND

Human genetic factors influence the outcome of pegylated interferon and ribavirin hepatitis C therapy. We explored the role of IL28B, APOH and ITPA SNPs on the outcomes of triple therapy including telaprevir or boceprevir in patients with compensated cirrhosis chronically infected with HCV-1.

PATIENTS AND METHODS

A total of 256 HCV-1 Caucasian treatment-experienced patients with compensated cirrhosis from the ANRS CO20-CUPIC cohort were genotyped for a total of 10 candidate SNPs in IL28B (rs12979860 and rs368234815), APOH (rs8178822, rs12944940, rs10048158, rs52797880, rs1801689 and rs1801690) and ITPA (rs1127354 and rs7270101). We tested the association of IL28B and APOH SNPs with sustained virological response and of ITPA SNPs with anemia related phenotypes by means of logistic regression assuming an additive genetic model.

RESULTS

None of the six APOH SNPs were associated with sustained virological response. The favorable alleles of the IL28B SNPs rs12979860 and rs368234815 were associated with sustained virological response (rs12979860: OR = 2.35[1.50-3.70], P = 2x10(-4)). Refined analysis showed that the effect of IL28B SNPs on sustained virological response was restricted to prior PegIFN/RBV relapse (OR = 3.80[1.82-8.92], P = 8x10(-4)). We also confirmed the association between ITPA low activity alleles and protection against early hemoglobin decline in triple therapy (P = 2x10(-5)).

CONCLUSION

Our results suggest that the screening of rs12979860 may remain interesting for decision making in prior relapse HCV-1 Caucasian patients with compensated cirrhosis eligible for a telaprevir- or boceprevir-based therapy.

Discovery of a Novel Human Pegivirus in Blood Associated with Hepatitis C Virus Co-Infection

Hepatitis C virus (HCV) and human pegivirus (HPgV), formerly GBV-C, are the only known human viruses in the Hepacivirus and Pegivirus genera, respectively, of the family Flaviviridae. We present the discovery of a second pegivirus, provisionally designated human pegivirus 2 (HPgV-2), by next-generation sequencing of plasma from an HCV-infected patient with multiple bloodborne exposures who died from sepsis of unknown etiology. HPgV-2 is highly divergent, situated on a deep phylogenetic branch in a clade that includes rodent and bat pegiviruses, with which it shares <32% amino acid identity. Molecular and serological tools were developed and validated for high-throughput screening of plasma samples, and a panel of 3 independent serological markers strongly correlated antibody responses with viral RNA positivity (99.9% negative predictive value). Discovery of 11 additional RNA-positive samples from a total of 2440 screened (0.45%) revealed 93–94% nucleotide identity between HPgV-2 strains. All 12 HPgV-2 RNA-positive cases were identified in individuals also testing positive for HCV RNA (12 of 983; 1.22%), including 2 samples co-infected with HIV, but HPgV-2 RNA was not detected in non-HCV-infected individuals (p<0.0001), including those singly infected by HIV (p = 0.0075) or HBV (p = 0.0077), nor in volunteer blood donors (p = 0.0082). Nine of the 12 (75%) HPgV-2 RNA positive samples were reactive for antibodies to viral serologic markers, whereas only 28 of 2,429 (1.15%) HPgV-2 RNA negative samples were seropositive. Longitudinal sampling in two individuals revealed that active HPgV-2 infection can persist in blood for at least 7 weeks, despite the presence of virus-specific antibodies. One individual harboring both HPgV-2 and HCV RNA was found to be seronegative for both viruses, suggesting a high likelihood of simultaneous acquisition of HCV and HPgV-2 infection from an acute co-transmission event. Taken together, our results indicate that HPgV-2 is a novel bloodborne infectious virus of humans and likely transmitted via the parenteral route.

To date, only one human hepacivirus (HCV) and one human pegivirus (HPgV-1/GBV-C) in the family Flaviviridae are known to exist. Using unbiased metagenomic next-generation sequencing, we discovered and assembled the genome of a novel pegivirus from plasma corresponding to an HCV-infected patient who died from unknown sepsis. This virus, provisionally named human pegivirus 2 (HPgV-2), is highly divergent, sharing <32% amino acid identity with its nearest relatives, a bat and rodent pegivirus. Identification and sequencing of 11 additional HPgV-2 viruses, revealing 93–94% identity between strains, as well as documented antibody responses using multiple markers, confirm that HPgV-2 is a bona fide novel infectious virus of humans. Several lines of evidence, including (1) a documented history of multiple bloodborne exposures in the index patient, (2) parallel detection of HPgV-2 and HCV RNA in an individual during the "window period" between infection and the appearance of detectable antibody, and (3) a tight observed association between HPgV-2 and HCV co-infection, suggest that HPgV-2 is an infectious agent capable of bloodborne transmission.

A method for rapid detection and genotype identification of hepatitis C virus 1-6 by one-step reverse transcription loop-mediated isothermal amplification

OBJECTIVE

Hepatitis C virus (HCV) is probably the leading cause of liver cirrhosis and hepatocellular carcinoma globally. Diagnostic tools conventionally used for the detection and identification of HCV infection are technically demanding, time-consuming, and costly for resource-limited environments. This study reports the development of the first rapid loop-mediated reverse transcription isothermal amplification assay that rapidly detects and identifies HCV genotypes in blood components.

METHODS

RNA extracted from donor plasma and serum specimens was applied to a one-step reverse transcription loop-mediated isothermal amplification reaction performed with HCV-specific oligonucleotides. Reactions were conducted at 63.5 °C for 30-60 min. The diagnostic characteristics of the assay were investigated and validated with clinical specimens.

RESULTS

Electrophoretic analysis of amplification revealed detection and identification of HCV genotypes 1-6. Positive amplification revealed unique ladder-like banding patterns that identified each HCV genotype. The assay demonstrated a sensitivity of 91.5% and specificity of 100%. Rapid naked-eye detection of HCV infection was facilitated by observation of an intense fluorescent glow of amplified targets under UV illumination.

CONCLUSION

These diagnostic characteristics highlight the potential utility of this assay for the rapid detection and genotype identification of HCV infection in field and point-of-care settings in endemic regions and resource-limited environments.

Hepatitis C genotype 4: The past, present, and future

Hepatitis C virus (HCV) genotype (GT) 4 represents 12%-15% (15-18 million) of total global HCV infection. It is prevalent in Northern and Equatorial Africa and the Middle East, and is also present in some countries in Europe. GT-4 (and subtype 4a in particular) dominates the HCV epidemic in Egypt. In underdeveloped countries, risk factors associated with HCV infection may be due to unsafe medical practices or other factors such as familial transmission, mother’s HCV status, or illiteracy. HCV prevention and control programs should include health education, increased community awareness towards the disease, controlling infection distribution in health-care centers, proper sterilization of medical and dental instruments, and ensuring safe supply of blood and blood-products. Response rates to a 48-wk combined pegylated-interferon (PEG-IFN) and ribavirin (RBV) treatment range from 40%-69%, and HCV-GT-4 has been considered better than GT-1 but worse than GT-2 and GT-3 in treatment with PEG-IFN/RBV. However, with the introduction of the HCV-GT-1 effective protease inhibitors boceprevir and telaprevir in 2011, HCV-GT-4 became the “most difficult (GT) to treat”. Recently, the direct-acting antivirals (DAAs) with pan- genotypic activities simeprevir, sofosbuvir, and daclatasvir have been recommended in triple regimens with PEG-IFN/RBV for the treatment of HCV-GT-4. An IFN-free regimen will be available for treatment of all genotypes of HCV in the near future. To date, several DAAs have been developed and are currently being evaluated in various combinations in clinical trials. As new regimens and new agents are being approved by the Food and Drug Administration, we can expect the guidelines for HCV treatment to be changed. The availability of shorter, simpler, and more tolerable treatment regimens can reduce the morbidity and mortality associated with HCV infection. With such a large number of therapeutic agents available, we can end up with a range of choices that we can select from to treat patients.