Review article: HCV genotype 3 – the new treatment challenge

Recompensation of Chronic Hepatitis C-Related Decompensated Cirrhosis Following Direct-Acting Antiviral Therapy: Prospective Cohort Study From a Hepatitis C Virus Elimination Program

BACKGROUND & AIMS

Chronic hepatitis C-related decompensated cirrhosis is associated with lower sustained virologic response (SVR)-12 rates and variable regression of disease severity after direct-acting antiviral agents. We assessed rates of SVR-12, recompensation (Baveno VII criteria), and survival in such patients.

METHODS

Between July 2018 and July 2023, patients with decompensated chronic hepatitis C-related cirrhosis after direct-acting antiviral agents treatment were evaluated for SVR-12 and then had 6-monthly follow-up.

RESULTS

Of 6516 patients with cirrhosis, 1152 with decompensated cirrhosis (age 53.2 ± 11.5 years; 63% men; Model for End-stage Liver Disease-Sodium [MELD-Na]: 16.5 ± 4.6; 87% genotype 3) were enrolled. SVR-12 was 81.8% after 1 course; ultimately SVR was 90.8% after additional treatment. Decompensation events included ascites (1098; 95.3%), hepatic encephalopathy (191; 16.6%), and variceal bleeding (284; 24.7%). Ascites resolved in 86% (diuretic withdrawal achieved in 24% patients). Recompensation occurred in 284 (24.7%) at a median time of 16.5 (interquartile range, 14.5-20.5) months. On multivariable Cox proportional hazards analysis, low bilirubin (adjusted hazard ratio [aHR], 0.6; 95% confidence interval [CI], 0.5-0.8; P < 0.001), international normalized ratio (aHR, 0.2; 95% CI, 0.1-0.3; P < 0.001), absence of large esophageal varices (aHR, 0.4; 95% CI, 0.2-0.9; P = 0.048), or gastric varices (aHR, 0.5; 95% CI, 0.3-0.7; P = 0.022) predicted recompensation. Portal hypertension progressed in 158 (13.7%) patients, with rebleed in 4%. Prior decompensation with variceal bleeding (aHR, 1.6; 95% CI, 1.2-2.8; P = 0.042), and presence of large varices (aHR, 2.9; 95% CI, 1.3-6.5; P < 0.001) were associated with portal hypertension progression. Further decompensation was seen in 221 (19%); 145 patients died and 6 underwent liver transplantation. A decrease in MELDNa of ≥3 was seen in 409 (35.5%) and a final MELDNa score of <10 was seen in 335 (29%), but 2.9% developed hepatocellular carcinoma despite SVR-12.

CONCLUSIONS

SVR-12 in hepatitis C virus-related decompensated cirrhosis in a predominant genotype 3 population led to recompensation in 24.7% of patients over a follow-up of 4 years in a public health setting. Despite SVR-12, new hepatic decompensation evolved in 19% and hepatocellular carcinoma developed in 2.9% of patients. (ClinicalTrials.gov, Number: NCT03488485).

Evaluation of patients treated with direct-acting anti-viral therapy for chronic hepatitis C and their risk of hepatocellular carcinoma in Hong Kong

BACKGROUND & AIM

To evaluate the risk of early hepatocellular carcinoma (HCC) in chronic hepatitis C patients treated with direct-acting antivirals (DAAs) in Hong Kong, as it has not been studied before in this locality.

METHODS

Three hundred thirty-three consecutive chronic hepatitis C patients treated with DAAs from two hospitals over the past 6 years were identified. Kaplan-Meier method was used to calculate cumulative HCC incidence. Cox regression was used to identify factors associated with HCC development.

RESULTS

During a median follow-up of 23.4 months after DAA started, 15 (5.4%, 95% CI 3.3-8.7%) out of 279 total included patients developed HCC. The overall sustained virological response (SVR) rate was 98.9%. The 1-year cumulative incidence for de-novo HCC and HCC recurrence were 0.8 and 30.9%, respectively (log-rank test p < 0.001). The 1-year cumulative HCC incidence for patients without and with cirrhosis were 0.7 and 5.1%, respectively (log-rank test p = 0.036). Univariate analysis showed that significant factors associated with HCC after DAA were: history of treated HCC, cirrhosis, evidence of portal hypertension, higher AFP at the start or end of DAA therapy, higher bilirubin, lower platelets, lower albumin, and older age. From receiver operating characteristic curve analysis, the optimal cut-off level of AFP for predicting HCC was 10.5 ng/mL at the start and 5.6 ng/mL at the end of DAA therapy.

CONCLUSIONS

The risk of early HCC recurrence remains high despite achieving SVR following DAA therapy, whereas the risk of early de-novo HCC occurence is low. AFP levels, both at the start and end of DAA therapy, can be useful in stratifying risks of HCC development.

Hepatitis C Retreatment With First-Line Direct Acting Antiviral Drugs

BACKGROUND AND AIMS

Sofosbuvir (S), daclatasvir (D), ledipasvir, or velpatasvir (V) containing first-line hepatitis C virus (HCV) treatment regimens fail to cure viremia in 5-10%. We report our experience of HCV retreatment using these first-line drugs, in a setting where second-line anti-HCV drugs are not available.

METHODS

Adults, who had relapsed after first complete course of a sofosbuvir-containing first-line, pegylated interferon free, anti-HCV treatment regimen with or without ribavirin (Riba) were included. Retreatment regimen, tailored to the failed anti-HCV regimen, was based on principle of using first-line drugs for 24 weeks with ribavirin and swapping between pangenotypic and genotype-specific regimens. Retreatment outcome was categorized as successful (achieved undetectable HCV RNA at the end of treatment [ETR] and sustained viral response at week 12 [SVR12]), non-responder (failed to achieve ETR), or relapse (achieved ETR but not achieved SVR12).

RESULTS

Twelve patients (9 male; 7 cirrhosis; all genotype 3) who had relapsed to prior anti-HCV treatment (4 SD12, 4 SD24, 1 SDRiba12, 1 SDRiba24, 2 SV12) were included. Following retreatment (2 SDRiba24, 10 SVRiba24), all achieved ETR but only 9 (75%) achieved SVR12. Two among three, in whom retreatment failed, achieved SVR12 following another course of sofosbuvir/velpatasvir/ribavirin for 24 weeks. Overall, 11/12 (92%) patients achieved SVR12 following retreatment with the first-line anti-HCV drugs.

CONCLUSION

HCV retreatment could be a treatment option if second-line anti-HCV drugs are not available. Successful retreatment could be achieved, in a large proportion, with the use of first-line drugs for 24 weeks with ribavirin and swapping of pangenotypic/genotype-specific regimens (NCT03483987).

Selection dynamics of HCV genotype 3 resistance-associated substitutions under direct-acting antiviral therapy pressure

The chronic hepatitis C (CHC) treatment is currently based on the use of direct-acting antivirals (DAAs), and patients infected with hepatitis C virus genotype 3 (GT3) have emerged as a more difficult-to-cure population. The NS5A inhibitor daclatasvir (DCV) and sofosbuvir (SOF), an NS5B viral polymerase inhibitor, are among the drugs that compose more effective and safer treatment regimens. The virus genetic variability is related to resistance-associated substitutions (RASs) that adversely impact DAAs effectiveness. The aims of this study were to analyze the association of NS5A and NS5B RASs and other clinical factors with DAAs regimens effectiveness in patients with GT3 CHC infection. This was a prospective cohort study performed in a Brazilian university hospital. Individuals older than 18 years with GT3 CHC treated with SOF + DCV ± ribavirin (RBV) or SOF + peginterferon (PEG) + RBV were included. Blood samples were collected at baseline and post-treatment. A total of 121 patients were included. Sustained virological response rates were 87.6% for the SOF + DCV ± RBV group and 80.0% for the SOF + PEG + RBV arm. Cirrhosis, prior treatment with interferon/PEG + RBV, and baseline NS5A RAS were associated with higher risk of treatment failure. The NS5A analysis suggested that A30K, Y93H, and RAS at site 62 were related to failure. Interestingly, a likely compensatory effect was shown between A30K and A62T. Emergence of Y93H was always associated with RAS at position 62. The RASs dynamics comprehension is an important tool to indicate more effective treatment for GT3 patients.

Changing clinical management of NAFLD in Asia

Non-alcoholic fatty liver disease (NAFLD) has become the leading cause of chronic liver disease, affecting approximately 25% of the world's population. Recently, because of the sedentary lifestyle and overnutrition resulting from urbanisation, the burden of NAFLD has rapidly increased in many Asian countries. Currently, the prevalence of NAFLD in Asia is approximately 30%, as is the case in many Western countries. In Asia, the prevalence and presentation of NAFLD vary widely across regions because of the substantial diversity in race, socioeconomic status and living environment. Furthermore, the dual aetiology of fatty liver, particularly with viral hepatitis in Asia, makes it complex and challenging to manage. Because Asians are likely to have central adiposity and insulin resistance, approximately 7%-20% of non-obese Asians with body mass indexes of less than 25 kg/m² are estimated to have NAFLD. Accumulating evidence indicates that NAFLD is associated with various extrahepatic comorbidities such as cardiovascular disease, chronic kidney disease, malignancy, in addition to liver-specific complications. Therefore, NAFLD should be managed as a multisystem disease in conjunction with metabolic syndrome. Lifestyle modification remains the basis of NAFLD management, but few patients can achieve adequate weight loss and maintain it long term. While various pharmacological agents are in phase 3 trials for steatohepatitis, Asian patients are underrepresented in most trials. This article reviews the epidemiological trends, clinical features, optimal assessment and current management practices for NAFLD in Asia.

Efficacy and safety of sofosbuvir/velpatasvir with or without ribavirin in hepatitis C genotype 3 compensated cirrhosis: A meta-analysis

BACKGROUND

Hepatitis C virus (HCV) is a leading cause of liver cirrhosis and hepatocellular carcinoma globally. Sofosbuvir/velpatasvir (SOF/VEL) is an effective pan-genotypic direct-acting antiviral combination for treatment of chronic HCV infection. While the addition of ribavirin (RBV) to SOF/VEL improved sustained virological response (SVR12) in genotype 3 (GT3) decompensated cirrhosis patients, the benefits of RBV in GT3 compensated cirrhosis patients receiving SOF/VEL remains unclear.

AIM

To evaluate the efficacy and safety of SOF/VEL, with or without RBV in GT3 compensated cirrhosis patients.

METHODS

We searched four electronic databases (PubMed/Medline, Embase, Cochrane Library and Web of Science) from inception up to June 2021 using both free text and MeSH terms. There was no restriction on language, geography, publication dates and publication status (full text or abstracts). All GT3 compensated cirrhosis patients treated with 12 wk of SOF/VEL, with or without RBV, were included, regardless of age, gender or prior treatment experience. The primary outcome was sustained virological response 12-wk post-treatment (SVR12). The secondary outcome was treatment-related adverse events, as defined by symptomatic anemia requiring transfusion or a drop in hemoglobin beyond 2 g/dL. The pooled relative risk (RR), 95%CI and heterogeneity (I 2) were estimated using Review Manager version 5.3.

RESULTS

From 1752 citations, a total of seven studies (2 randomized controlled trials, 5 cohort studies) with 1088 subjects were identified. The SVR12 was similar in GT3 compensated cirrhosis patients, regardless of the use of RBV, for both the intention-to-treat RR 1.03, 95%CI: 0.99-1.07; I 2 = 0%) and the per-protocol analysis (RR: 1.03, 95%CI: 0.99-1.07; I 2 = 48%). The overall pooled rate of treatment-related adverse events was 7.2%. Addition of RBV increased the pooled risk of treatment-related adverse events in GT3 compensated cirrhosis patients receiving SOF/VEL (RR: 4.20, 95%CI: 1.29-13.68; I 2 = 0%). Subgroup analysis showed that RBV was associated with a higher SVR12 in GT3 compensated cirrhosis patients with baseline resistance-associated substitutions. However, addition of RBV did not significantly increase the SVR12 among treatment-experienced GT3 compensated cirrhosis patients.

CONCLUSION

Ribavirin was not associated with higher SVR12 in GT3 compensated cirrhosis patients receiving SOF/VEL. Our findings suggest a limited role for RBV as routine add-on therapy to SOF/VEL in GT3 compensated cirrhosis patients.

Phylogenetic signature and prevalence of natural resistance-associated substitutions for hepatitis C virus genotypes 3a and 3b in southwestern China

Background

Patients infected with hepatitis C (HCV) genotype (GT) 3, especially GT3b, are still difficult to cure. GT3b is more common than GT3a in southwestern China. Here we aimed to investigate the prevalence of naturally occurring RASs in HCV GT3 in southwestern China and performed phylogenetic analysis.

Methods

Serum samples were collected from patients with HCV GT3 infection. Sanger sequencing was used to validate resistance-associated substitutions (RASs). Phylogenetic analysis was performed using MEGA X and the observed-minus-expected-squared algorithm was used to analyze amino acid covariance.

Results

A total of 136 patients were enrolled, including 41 HCV GT3a and 95 GT3b infected patients. In the NS5A region, the proportion of RASs found in GT3b (99%) was notably higher than in GT3a (9%). In the NS3 region, RASs prevalence in GT3b (5%) was lower than in GT3a (24%). NS5B-specific RASs were rare. Both the NS5A30k and L31 M substitutions occurred in 96% of GT3b sequences. The A30K + L31M combination was found in 94% of GT3b isolates, however, there were no A30K or L31M mutations observed in the GT3a sequence.

Conclusions

Significant differences were observed between HCV GT3a and GT3b in terms of RAS prevalence. The origin of GT3a appears to be more diverse compared with GT3b in southern China. Studies specifically aimed at HCV GT3b infection should be initiated to gain more insight into this subtype.

The influence of hepatitis C virus eradication on hepatocarcinogenesis in patients with hemophilia

INTRODUCTION AND OBJECTIVES

Hepatitis C virus (HCV) infections in patients with hemophilia lead to the development of hepatocellular carcinoma (HCC) at a relatively younger age than that in patients without hemophilia. Although recent progress in direct-acting-antivirals has facilitated a high rate of sustained virological response (SVR), the clinical influence of HCV eradication in hemophilia patients remains unclear. This study aimed to compare the clinical outcomes of SVR against HCV in patients with and without hemophilia.

PATIENTS AND METHODS

The study enrolled 699 patients who achieved SVR after HCV antiviral treatment. Patients were divided into two groups: 78 patients with hemophilia (H group) and 621 patients without hemophilia (NH group). We evaluated patient characteristics, clinical outcomes, and the cumulative incidence of HCC after SVR.

RESULTS

Compared with the NH group, patients in the H-group were significantly younger and had a lower hepatic fibrosis score. No difference was found in the incidence of liver-related disease or overall death between the two groups over a mean follow-up period of 7 years. Four patients in the H group and 36 patients in the NH group were diagnosed with HCC after SVR. Multivariate analysis showed that male sex, age, and cirrhosis were significant risk factors for HCC incidence. There was no significant difference in the cumulative incidence of HCC after propensity-score matching adjusting for the risk factors of HCC between the two groups.

CONCLUSION

Hemophilia is not a significant risk factor for hepatocarcinogenesis after SVR against HCV.

Use of Sofosbuvir/Velpatasvir/Voxilaprevir for Sofosbuvir Nonresponder Genotype 3 HCV Infection in India

In India, hepatitis C virus (HCV) infection is treated with sofosbuvir in combination with NS5A inhibitor (Daclatasvir, Ledipasvir, or Velpatasvir). A small proportion of them fail to achieve sustained virological response at 12 weeks (SVR12) and need retreatment. Triple-drug combination (Sofosbuvir/Velpatasvir/Voxilaprevir) is one of the options for retreatment. Here we describe a patient with cirrhosis and genotype 3a infection who was successfully treated with a triple-drug combination after relapse with two courses of Sofosbuvir-containing regimens.

Direct-acting antivirals for chronic hepatitis C treatment: The experience of two tertiary university centers in Brazil

BACKGROUND

Hepatitis C virus (HCV) treatment has undergone major changes in recent years. Previous interferon-based therapies have been replaced by oral direct-acting antivirals (DAA) regimens, with high sustained virologic response (SVR) rates, and a lower incidence of adverse events (AEs).

AIM

To evaluate the efficacy and safety of DAAs for HCV treatment in subjects from two tertiary university centers in Brazil.

METHODS

This is a multicenter retrospective cohort study of 532 patients with chronic hepatitis C (CHC), undergoing treatment with interferon-free regimens from November 2015 to November 2019. The therapeutic regimen was defined by the current Brazilian guidelines for HCV management at the time of treatment. Demographic, anthropometric, clinical, and laboratory variables were evaluated. SVRs were assessed at 12 to 24 wk after therapy by intention-to-treat (ITT), and modified ITT (m-ITT) analysis. AEs and serious adverse events (SAEs) were registered. In the statistical analysis, a P value of < 0.05 was considered significant.

RESULTS

The mean age was 56.88 years, with 415 (78.5%) being HCV genotype 1, followed by genotype 3 (20.1%). Moreover, 306 (57.5%) subjects had cirrhosis, and a third of them had decompensated cirrhosis. Sofosbuvir (SOF) plus daclatasvir ± ribavirin was the most frequently used treatment (66.9%), followed by SOF plus simeprevir (21.2%). The overall ITT SVR was 92.6% (493/532), while the m-ITT SVR was 96.8% (493/509). Variables associated with treatment failure via ITT evaluation were hepatic encephalopathy (OR: 4.320; 95%CI: 1.920-9.721, P = 0.0004), presence of esophageal varices (OR: 2.381; 95%CI: 1.137-4.988, P = 0.0215), previous portal hypertensive bleeding (OR: 2.756; 95%CI: 1.173-6.471, P = 0.02), higher model for end-stage liver disease scores (OR: 1.143, 95%CI: 1.060-1.233, P = 0.0005), lower serum albumin levels (OR: 0.528, 95%CI: 0.322-0.867, P = 0.0115), higher serum creatinine (OR: 1.117, 95%CI: 1.056-1.312, P = 0.0033), and international normalized ratio (INR) levels (OR: 5.542, 95%CI: 2.023-15.182, P = 0.0009). AEs were reported in 41.1% (211/514) of patients, and SAEs in 3.7%. The female gender, higher body mass index, esophageal varices, higher INR values, and longer treatment duration were independently associated with AE occurrence.

CONCLUSION

Treatment with oral DAAs attains a high SVR rate, with fewer SAEs in a real-life cohort of subjects with CHC, from two tertiary university centers in Brazil.

Epidemiology and Clinical Characteristics of Individuals with Hepatitis C Virus Infection in the United States, 2017-2019

Introduction

Hepatitis C virus (HCV) is the most common bloodborne chronic infection in the US. Following approval of highly effective, direct-acting antivirals in 2014, the diagnostic and treatment rates for HCV infection in the US have evolved. This study assessed the number of individuals with HCV screening or diagnostic testing and the clinical characteristics and treatment of HCV-infected individuals between 2017 and 2019.

Methods

Individuals screened for HCV antibody and/or tested for HCV ribonucleic acid (RNA) from 2017 to 2019 by two large US laboratory companies were included in this analysis. Clinical characteristics, such as HCV genotype, fibrosis stage, HIV coinfection and demographics, were assessed in HCV RNA-positive individuals. HCV treatment and subsequent achievement of sustained virologic response were imputed using data-driven algorithms based on successive viral load decline and negativity.

Results

From 2017 to 2019, the number of individuals tested for HCV antibody increased by 5.7%, from 7,580,303 in 2017 to 8,009,081 in 2019. The percentage of individuals tested who were HCV antibody positive was stable, ranging from 5.0% in 2017 to 4.9% in 2018 and 2019. The number of HCV RNA-positive individuals decreased by 5.0% from 382,500 in 2017 to 363,532 in 2019. Of HCV RNA-positive individuals, the proportions with genotype (GT) 3 and minimal fibrosis increased over time; proportions of individuals aged < 40 years increased, while the proportion aged 50 to 59 years decreased. Treatment rates increased from 23.4% in 2017 to 26.8% in 2019.

Conclusions

The percentage of HCV antibody-positive individuals remained stable from 2017 to 2019. The number of individuals tested HCV RNA positive decreased over the years. Demographics shifted toward a younger population with less fibrosis and higher rates of GT3. More than 70% of diagnosed individuals were not treated during this interval, highlighting a need for unfettered access to treatment.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-021-01928-y.

Sofosbuvir/Velpatasvir - A Promising Treatment for Chronic Hepatitis C Virus Infection

Hepatitis C virus (HCV) infection is a disease that affects millions of people worldwide and has an enormous global public health impact. Chronic HCV is a long-term infection that goes unnoticed until the virus destroys the liver enough to induce liver disease symptoms. The inadequate and poorly tolerated treatment contributes to the burden of chronic HCV. Treatments have improved over time - direct-acting antivirals (DAAs) that targeted different hepatitis C virus genomic sites have shown to be more effective and well-tolerated. Patients recover to a greater extent following a treatment regimen based on DAAs. We conducted this literature review to investigate the effectiveness of these medications in treating chronic HCV infection. Relevant articles were identified by searching PubMed and Google scholar databases. Our primary goal was to analyze the efficacy and safety of the DAA, sofosbuvir plus velpatasvir, with or without ribavirin, in cirrhotic or non-cirrhotic, naïve or previously treated, chronic HCV patients. We found that treating patients with sofosbuvir-velpatasvir for 12 weeks was highly effective with fewer adverse events, including those with compensated cirrhosis. The outcomes aided in improving HCV treatment, lowering the disease's burden and fatality rate.

Distribution of HCV Genotypes Among People Who Inject Drugs in Tunisia: New Evidence for Scaling Up Prevention and Treatment Toward National Elimination Goal

Little is known about the distribution of hepatitis C virus (HCV) genotypes among people who inject drugs (PWID) in North African countries, including Tunisia. This study aims to describe HCV genotypes circulating among Tunisian PWID. A cross-sectional study was conducted, and 128 HCV-positive PWID were recruited between 2018 and 2019 from community-based harm reduction centers. After informed consent, sociodemographic characteristics and risk behavior data were obtained using an interviewer-administrated questionnaire. Blood samples were collected for further serological and molecular testing. Overall, five women and 123 men were included. The median age was 39.5 years. The majority of PWID (56.3%) had less than a secondary level of education, were single (57%), were unemployed (65.6%), were incarcerated at least once (93.0%), and had a history of residency in at least one foreign country (50.8%). During the previous 12 months, 82.0% reported having reused syringes at least once, 43.8% shared syringes at least once, while 56.2% had at least one unprotected sexual relation, and 28.1% had more than two different sexual partners. Tattooing was reported among 60.2%. All positive results for HCV-infection by rapid testing were confirmed by enzyme-linked immunosorbent assay (ELISA). HCV-RNA was detectable in 79.7%. Genotyping showed a predominance of genotype 1 (52%) followed by genotype 3 (34%) and genotype 4 (10%). Four patients (4%) had an intergenotype mixed infection. Subtyping showed the presence of six different HCV subtypes as follows: 1a (53.2%), 1b (6.4%), 3a (33.0%), 4a (3.2%), and 4d (4.3%). This is the first study describing circulating HCV genotypes among PWID in Tunisia. The distribution of HCV genotypes is distinct from the general population with a predominance of subtypes 1a and 3a. These findings can be used to guide national efforts aiming to optimize the access of PWID to relevant HCV prevention and treatment measures including pangenotypic regimens for patients infected with HCV genotype 3.

The Inflammatory Relationship Between Hepatitis C Virus With Coronary and Carotid Atherosclerosis

Hepatitis C virus (HCV), a global health concern, has been linked to various hepatic and extrahepatic deleterious manifestations. Several observational studies have either supported the increased likelihood of coronary and carotid atherosclerosis after infection with HCV or refuted it. To date, there has been no clear consensus to support either train of thought, as randomized, controlled clinical trials have not been completed. In this review, we first discuss articles that support the notion that HCV infection leads to increased plaque formation due to systemic inflammation and then focus on articles that refute this idea. From the literature, we do know that both inflammatory and lipid processes play a role in plaque formation, and thus both components are important in the successful treatment of atherosclerosis. Based on our review of the literature, we do believe that HCV-infected individuals are at an increased risk for more severe coronary artery disease than their healthy counterparts. Although there is no irrefutable evidence that links HCV infection with plaque formation and/or rupture, cardioprotective measures should be taken to reduce poor health outcomes, especially in those individuals who are already at risk of coronary disease.

Comparative Analysis of Within-Host Mutation Patterns and Diversity of Hepatitis C Virus Subtypes 1a, 1b, and 3a

Understanding within-host evolution is critical for predicting viral evolutionary outcomes, yet such studies are currently lacking due to difficulty involving human subjects. Hepatitis C virus (HCV) is an RNA virus with high mutation rates. Its complex evolutionary dynamics and extensive genetic diversity are demonstrated in over 67 known subtypes. In this study, we analyzed within-host mutation frequency patterns of three HCV subtypes, using a large number of samples obtained from treatment-naïve participants by next-generation sequencing. We report that overall mutation frequency patterns are similar among subtypes, yet subtype 3a consistently had lower mutation frequencies and nucleotide diversity, while subtype 1a had the highest. We found that about 50% of genomic sites are highly conserved across subtypes, which are likely under strong purifying selection. We also compared within-host and between-host selective pressures, which revealed that Hyper Variable Region 1 within hosts was under positive selection, but was under slightly negative selection between hosts, which indicates that many mutations created within hosts are removed during the transmission bottleneck. Examining the natural prevalence of known resistance-associated variants showed their consistent existence in the treatment-naïve participants. These results provide insights into the differences and similarities among HCV subtypes that may be used to develop and improve HCV therapies.

Impact of hepatitis C virus genotype 3 on liver disease progression in a Chinese national cohort

Supplemental Digital Content is available in the text

Background:

Hepatitis C virus (HCV) genotype 3, particularly subtype 3b, is increasing in prevalence and distribution in China. This study evaluated the prevalence, regional distribution, clinical characteristics, host factors, treatment outcomes, and disease progression of patients with HCV genotype 3 in China.

Methods:

A 5-year follow-up was preceded by a cross-sectional study. Treatment choices were at the discretion of treating physicians. Estimated infection time to overall-disease-progression (defined by ≥1 of: newly diagnosed cirrhosis; cirrhosis at baseline, Child-Turcotte-Pugh score increased 2 points or more; progression from compensated cirrhosis to decompensated cirrhosis; hepatocellular carcinoma; liver transplantation; or death) was calculated using the Kaplan-Meier method. Cox regression analyses were conducted to evaluate the risk factors for disease progression.

Results:

The cross-sectional study enrolled 997 patients, including 91 with HCV genotype 3 infection. Among them, subtype 3b (57.1%) was more dominant than subtype 3a (38.5%). Five hundred and twelve patients were included into the follow-up phase. Among patients analyzed for estimated infection time to overall-disease-progression, 52/304 (17.1%) patients with HCV genotype 1 and 4/41 (9.8%) with HCV genotype 3 (4/26 with genotype 3b, 0/13 with genotype 3a, and 0/2 with undefined subtype of genotype 3) experienced overall-disease-progression. Patients with HCV genotype 3 were younger than those with genotype 1 (mean age: 39.5 ± 8.7 vs. 46.9 ± 13.6 years) and demonstrated more rapid disease progression (mean estimated infection time to overall-disease-progression 27.1 vs. 35.6 years).

Conclusions:

HCV genotype 3, specifically subtype 3b, is associated with more rapid progression of liver disease. Further analysis to compare HCV subtype 3a and 3b is needed in high prevalence regions.

Trial registration:

NCT01293279, https://clinicaltrials.gov/ct2/show/NCT01293279; NCT01594554, https://clinicaltrials.gov/ct2/show/NCT01594554.

Fitness-associated substitutions following failure of direct-acting antivirals assessed by deep sequencing of full-length hepatitis C virus genomes

BACKGROUND

In hepatitis C virus (HCV) infection, treatment failure is generally associated with the selection of resistance-associated substitutions (RAS) conferring reduced susceptibility to direct-acting antiviral (DAA) drugs. Resistant variants continue to replicate after the end of treatment with potential for transmission. This may result from the selection of "fitness-associated substitutions".

AIM

To characterise potential "fitness-associated substitutions" in patients infected with genotype 3a failing DAA drugs METHODS: By means of shotgun metagenomics, we sequenced full-length HCV genomes at treatment initiation and at virological relapse in eight patients infected with genotype 3a with cirrhosis failing sofosbuvir and an NS5A inhibitor. The impact of amino acid changes occurring outside of DAA target regions selected in at least two patients were assessed on the in vitro susceptibility to an NS5A inhibitor and replication capacity.

RESULTS

At treatment failure, besides selection of known NS5A RASs, especially Y93H, a large number of amino acid changes was observed outside of DAA target regions. We identified four amino acid positions at which observed changes substantially improved in vitro replication capacity without affecting NS5A inhibitor susceptibility.

CONCLUSIONS

This is the first in vivo observation combined with in vitro confirmation of selection of phenotypically characterised "fitness-associated substitutions" together with RASs at the time of sofosbuvir-NS5A inhibitor treatment failure in patients infected with genotype 3a with cirrhosis. Our findings may explain the persistence of resistant HCV variants after treatment in patients who did not achieve sustained virological remission.

Rational drug discovery: Ellagic acid as a potent dual-target inhibitor against hepatitis C virus genotype 3 (HCV G3) NS3 enzymes

Structure-based virtual screening (SBVS) has served as a popular strategy for rational drug discovery. In this study, we aimed to discover novel benzopyran-based inhibitors that targeted the NS3 enzymes (NS3/4A protease and NS3 helicase) of HCV G3 using a combination of in silico and in vitro approaches. With the aid of SBVS, six novel compounds were discovered to inhibit HCV G3 NS3/4A protease and two phytochemicals (ellagic acid and myricetin) were identified as dual-target inhibitors that inhibited both NS3/4A protease and NS3 helicase in vitro (IC₅₀  = 40.37 ± 5.47 nm and 6.58 ± 0.99 µm, respectively). Inhibitory activities against the replication of HCV G3 replicons were further assessed in a cell-based system with four compounds showed dose-dependent inhibition. Compound P8 was determined to be the most potent compound from the cell-based assay with an EC₅₀ of 19.05 µm. The dual-target inhibitor, ellagic acid, was determined as the second most potent (EC₅₀  = 32.37 µm) and the most selective in its inhibitory activity against the replication of HCV replicons, without severely affecting the viability of the host cells (selectivity index > 6.18).

Hepatitis C virus infection and new treatment strategies

Hepatitis C is a major public health problem worldwide. This disease is caused by the hepatitis C virus, which is characterised by its genetic diversity. The infection is usually asymptomatic. However, between 60% and 80% of HCV-infected individuals will progress to chronic hepatitis, 20% to liver cirrhosis in the medium-to long-term and, each year, between 1% and 4% of these patients with cirrhosis will develop hepatocellular carcinoma (HCC). A Spanish consensus document has recently been drafted to diagnose hepatitis C in a single step, consisting of active investigation (antibodies and viremia) in a single sample, which according to the experts, would reduce the time to access treatment and avoid tracking losses. To definitively change the hepatitis C treatment paradigm, direct-acting antiviral drugs (DAAs) have been approved, whose development has been based on achieving cure rates close to 100% regardless of the genotype of the virus, ie, pangenotypes, with good tolerance and bioavailability. These drugs have constituted a real therapeutic revolution. Supplement information: This article is part of a supplement entitled «SEIMC External Quality Control Programme. Year 2016», which is sponsored by Roche, Vircell Microbiologists, Abbott Molecular and Francisco Soria Melguizo, S.A. © 2019 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosasy Microbiología Clínica. All rights reserved.

Comparison of three therapeutic regimens for genotype-3 hepatitis C virus infection in a large real-life multicentre cohort

BACKGROUND & AIMS

In the direct-acting antiviral era, treatment of genotype-3 HCV (HCV-GT3) is still challenging. Real-life comparisons between recommended regimens, sofosbuvir (SOF)+daclatasvir (DAC), SOF/velpatasvir (VEL), glecaprevir/pibrentasvir (GLE/PIB), are scarce. We aimed at filling this data gap.

METHODS

Sustained virological response 12 weeks after treatment completion (SVR12) was assessed for all HCV-GT3 patients consecutively treated within the Lombardia web-based Navigatore HCV-Network; differences in SVR12 across regimens were evaluated by logistic regression.

RESULTS

Of the 2082 subjects with HCV-GT3, 1544 were evaluable for comparisons between regimens: SOF + DAC (1023, 66.2%), SOF/VEL (369, 23.9%), GLE/PIB (152, 9.8%). Patients treated with former regimens were more frequently male, cirrhotic, HIV-positive, pretreated, used ribavirin in their regimen, and had lower baseline HCV-RNA. SVR12 was similar across groups: 94.8% in SOF + DAC, 97.6% in SOF/VEL, 96.7% in GLE/PIB (P = .065). At univariate analysis, SVR12 was associated with female gender (97.9% vs 94.8%, P = .007) and lower median pretreatment Log₁₀ HCV-RNA (5.87 vs 6.20, P = .001). At multivariate logistic regression analysis, treatment with SOF/VEL was associated with a higher likelihood of SVR12 than SOF + DAC, but only in the absence of ribavirin (98% vs 90.3%). Female gender and lower pretreatment HCV-RNA were independently associated with SVR12.

CONCLUSIONS

In a large real-life setting of HCV-GT3-infected patients with a high proportion of cirrhosis, the success rate was remarkable. The slight advantage of SOF/VEL on SOF + DAC was significant only without ribavirin. The current prescription shift towards novel regimens (ie SOF/VEL and GLE/PIB) in easier-to-treat patients allows ribavirin-free and shorter schedules without mining SVR12 in this <<difficult-to-treat>> genotype.

Targeting histone epigenetics to control viral infections

During the past decades, many studies have significantly broadened our understanding of complex virus-host interactions to control chromatin structure and dynamics.1, 2 However, the role and impact of such modifications during viral infections is not fully revealed. Indeed, this type of regulation is bidirectional between the virus and the host. While viral replication and gene expression are significantly impacted by histone modifications on the viral chromatin,³ studies have shown that some viral pathogens dynamically manipulate cellular epigenetic factors to enhance their own survival and pathogenesis, as well as escape the immune system defense lines.⁴ In this dynamic, histone posttranslational modifications (PTMs) appear to play fundamental roles in the regulation of chromatin structure and recruitment of other factors.⁵ Genuinely, those PTMs play a vital role in lytic infection, latency reinforcement, or, conversely, viral reactivation.⁶ In this chapter, we will examine and review the involvement of histone modifications as well as their potential manipulation to control infections during various viral life cycle stages, highlighting their prospective implications in the clinical management of human immunodeficiency virus (HIV), herpes simplex virus (HSV), human cytomegalovirus (HCMV), hepatitis B and C viruses (HBV and HCV, respectively), Epstein–Barr virus (EBV), and other viral diseases. Targeting histone modifications is critical in setting the treatment of chronic viral infections with both lytic and latent stages (HIV, HCMV, HSV, RSV), virus-induced cancers (HBV, HCV, EBV, KSHV, HPV), and epidemic/emerging viruses (e.g. influenza virus, arboviruses).

Exploring the interactions between the human and viral genomes

Over the last decade, genome-wide association studies led to major advances in identifying human genetic variants associated with infectious disease susceptibility. On the pathogen side, comparable methods are now applied to identify disease-modulating pathogen variants. As host and pathogen variants jointly determine disease outcomes, the most recent development has been to explore simultaneously host and pathogen genomes, through so-called genome-to-genome studies. In this review, we provide some background on the development of genome-to-genome analysis and we detail the first wave of studies in this emerging field, which focused on patients chronically infected with HIV and hepatitis C virus. We also discuss the need for novel statistical methods to better tackle the issues of population stratification and multiple testing. Finally, we speculate on future research areas where genome-to-genome analysis may prove to be particularly effective.

Resistance analysis of genotype 3 hepatitis C virus indicates subtypes inherently resistant to nonstructural protein 5A inhibitors

Hepatitis C virus (HCV) genotype (gt) 3 is highly prevalent globally, with non-gt3a subtypes common in Southeast Asia. Resistance-associated substitutions (RASs) have been shown to play a role in treatment failure. However, the role of RASs in gt3 is not well understood. We report the prevalence of RASs in a cohort of direct-acting antiviral treatment-naive, gt3-infected patients, including those with rarer subtypes, and evaluate the effect of these RASs on direct-acting antivirals in vitro. Baseline samples from 496 gt3 patients enrolled in the BOSON clinical trial were analyzed by next-generation sequencing after probe-based enrichment for HCV. Whole viral genomes were analyzed for the presence of RASs to approved direct-acting antivirals. The resistance phenotype of RASs in combination with daclatasvir, velpatasvir, pibrentasvir, elbasvir, and sofosbuvir was measured using the S52 ΔN gt3a replicon model. The nonstructural protein 5A A30K and Y93H substitutions were the most common at 8.9% (n = 44) and 12.3% (n = 61), respectively, and showed a 10-fold and 11-fold increase in 50% effect concentration for daclatasvir compared to the unmodified replicon. Paired RASs (A30K + L31M and A30K + Y93H) were identified in 18 patients (9 of each pair); these combinations were shown to be highly resistant to daclatasvir, velpatasvir, elbasvir, and pibrentasvir. The A30K + L31M combination was found in all gt3b and gt3g samples. Conclusion: Our study reveals high frequencies of RASs to nonstructural protein 5A inhibitors in gt3 HCV; the paired A30K + L31M substitutions occur in all patients with gt3b and gt3g virus, and in vitro analysis suggests that these subtypes may be inherently resistant to all approved nonstructural protein 5A inhibitors for gt3 HCV. (Hepatology 2018).

Comparison of the efficacy of sofosbuvir plus ribavirin in Chinese patients with genotype 3a or 3b HCV infection

BACKGROUND AND AIM

Genotype 3b hepatitis C virus (HCV) infection represents approximately 50% of patients with genotype 3 in China. We compared the efficacy of sofosbuvir (SOF) plus ribavirin (RBV) in Chinese patients with genotype 3a and 3b HCV.

METHODS

The analyzed data are from a phase 3, open-label study of SOF plus RBV for 24 weeks conducted in China. The primary endpoint for the trial was sustained virologic response at 12 weeks after the end of therapy (SVR12).

RESULTS

Of 126 patients included in this analysis, 58 (46%) had genotype 3a and 68 (54%) had genotype 3b. Both the subtypes were similar in age, sex, body mass index, IL28B, and baseline HCV RNA. However, more treatment-experienced and cirrhotic patients were in the genotype 3b group. All 100% of patients with genotype 3a (95% confidence interval [CI], 94-100), and 91% (95% CI, 82-97) of patients with genotype 3b achieved SVR12 (P = 0.030). For treatment-experienced patients with genotype 3b, the SVR12 rate was 73% (95% CI, 39-94) and 88% (95% CI, 64-99) among patients with and without cirrhosis (P = 1.00), respectively.

CONCLUSION

SOF plus RBV for 24 weeks in patients with HCV genotype 3 infection resulted in high rates of SVR. However, the SVR12 rate among patients with genotype 3b was lower than that observed in patients with genotype 3a infection, particularly among treatment-experienced patients with cirrhosis.

Hepatitis C virus genotype 3 was associated with the development of hepatocellular carcinoma in Korea

Although hepatitis C virus (HCV) genotype 3 infection is thought to be an important risk factor for hepatocellular carcinoma (HCC), current evidence is limited because only a few Western studies have evaluated the occurrence of HCC in patients with HCV genotype 3 infection. We evaluated the impact of genotype 3 and non-3 on HCC incidence and on disease progression in chronic HCV patients; this is the first study reporting such findings in an Asian population. We performed a retrospective cohort study using the data of 1448 consecutive chronic HCV patients evaluated at three centres in Korea between January 2005 and December 2016. Of these, 604, 675 and 169 had genotype 1, genotype 2 and genotype 3 HCV infections, respectively. Over a mean follow-up period of 53.2 months, 75 and 143 patients of all the patients developed HCC and experienced disease progression, respectively. The incidences of HCC were 1.10, 0.92 and 2.50 per 100 person-years, and those of disease progression were 1.95, 1.62 and 6.72 per 100 person-years for HCV genotypes 1, 2 and 3, respectively. In multivariate Cox regression analysis, genotype 3 was associated with an increased risk of HCC (hazard ratio [HR] = 4.26, 95% confidence interval [CI] = 2.02-8.97) and an increased risk of disease progression (HR = 4.88, 95%; CI = 2.94-8.08). Our study proposes that HCV genotype 3 is an independent risk factor for HCC and disease progression in chronic HCV patients.

Subtype-Specific Prevalence of Hepatitis C Virus NS5A Resistance Associated Substitutions in Mainland China

Resistance associated substitutions (RASs) can reduce the efficacy of direct-acting antiviral agents (DAAs) targeting hepatitis C virus (HCV) and lead to treatment failure. Clinical data of HCV NS5A RASs prevalence are limited in China and need to be investigated. A total of 878 unique patient samples with different genotypes (GT) (1b: n = 489, 2a: n = 203, 3a: n = 60, 3b: n = 78, 6a: n = 48) were collected from around mainland China by KingMed Laboratory and analyzed for NS5A RASs distribution by Sanger sequencing. Phylogeographic analyses based on NS5A domain 1 sequences indicated circulation of both locally and nationally epidemic strains. Relatively high frequency of Y93H (14.1%) was only detected in GT1b but not in other subtypes. High frequency of L31M was found in both GT2a (95.6%) and GT3b (98.7%) sequences. Due to the overlapping incidence of A30K, 96% of GT3b isolates had NS5A RASs combination A30K + L31M, which confers high levels of resistance to most NS5A inhibitors. No RASs were detected in GT6a strains. Meanwhile, baseline NS5A RASs fingerprints were also evaluated in 185 DAA treatment-naive GT1b patients with next generation sequencing method. Patients presenting with Y93H had statistically higher entropy of HCV NS5A sequences. Taken together, subtype-specific distribution patterns of NS5A RASs were observed. GT1b patients with higher HCV complexity tend to have a greater chance of Y93H presence, while GT3b patients are naturally resistant to current NS5A inhibitors and their treatment may pose a challenge to real-world DAA application.

Glecaprevir/Pibrentasvir in patients with chronic HCV genotype 3 infection: An integrated phase 2/3 analysis

Glecaprevir coformulated with pibrentasvir (G/P) is approved to treat hepatitis C virus (HCV) infection and was highly efficacious in phase 2 and 3 studies. Treating HCV genotype (GT) 3 infection remains a priority, as these patients are harder to cure and at a greater risk for liver steatosis, fibrosis progression and hepatocellular carcinoma. Data were pooled from five phase 2 or 3 trials that evaluated 8-, 12- and 16-week G/P in patients with chronic HCV GT3 infection. Patients without cirrhosis or with compensated cirrhosis were either treatment-naïve or experienced with interferon- or sofosbuvir-based regimens. Safety and sustained virologic response 12 weeks post-treatment (SVR12) were assessed. The analysis included 693 patients with GT3 infection. SVR12 was achieved by 95% of treatment-naïve patients without cirrhosis receiving 8-week (198/208) and 12-week (280/294) G/P. Treatment-naïve patients with cirrhosis had a 97% (67/69) SVR12 rate with 12-week G/P. Treatment-experienced, noncirrhotic patients had SVR12 rates of 90% (44/49) and 95% (21/22) with 12- and 16-week G/P, respectively; 94% (48/51) of treatment-experienced patients with cirrhosis treated for 16 weeks achieved SVR12. No serious adverse events (AEs) were attributed to G/P; AEs leading to study drug discontinuation were rare (<1%). G/P was well-tolerated and efficacious for patients with chronic HCV GT3 infection, regardless of cirrhosis status or prior treatment experience. Eight- and 12-week durations were efficacious for treatment-naïve patients without cirrhosis and with compensated cirrhosis, respectively; 16-week G/P was efficacious in patients with prior treatment experience irrespective of cirrhosis status.

Glecaprevir/pibrentasvir in patients with chronic HCV and recent drug use: An integrated analysis of 7 phase III studies

BACKGROUND

Injection drug use is the primary mode of transmission for hepatitis C virus (HCV), and treatment guidelines recommend treating HCV-infected people who use drugs; however, concerns about adherence, effectiveness, and reinfection have impeded treatment uptake.

METHODS

Data were pooled from seven phase III trials that evaluated the efficacy and safety of 8 or 12 weeks of glecaprevir/pibrentasvir (G/P) in patients chronically infected with HCV genotypes 1-6. Patients had compensated liver disease, with or without cirrhosis, and were HCV treatment-naïve or -experienced with interferon or pegylated interferon ± ribavirin, or sofosbuvir plus ribavirin ± pegylated interferon. Patients were grouped into recent drug users (injection drug use ≤12 months before screening, positive urine drug screen [UDS], and/or drug-related adverse event), former drug users (>12 months before screening and negative UDS), or non-drug users. Assessments included sustained virologic response at 12 weeks posttreatment (SVR12), treatment adherence, and safety.

RESULTS

Among 1819 patients, 5%, 34%, and 61% were recent, former, and non-drug users, respectively. Treatment adherence and completion were high (≥96%) regardless of drug use status. SVR12 was achieved by 93% (n/N = 91/98), 97% (n/N = 591/610), and >99% (n/N = 1106/1111) of recent, former, and non-drug users, respectively (intention-to-treat analysis). The overall rates of virologic failure were ≤1.5% across all three subpopulations, with no HCV reinfections among recent drug users. Drug-related serious adverse events and adverse events leading to treatment discontinuation were experienced by ≤1% of patients.

CONCLUSIONS

G/P is a well-tolerated and efficacious pangenotypic regimen for chronic HCV-infected people with recent or active drug use.

Findings from a large Asian chronic hepatitis C real-life study

There is a paucity of information on chronic hepatitis C (CHC) patients treated with direct antiviral agents (DAAs) in Asia. We invited Asia-Pacific physicians to collate databases of patients enrolled for CHC treatment, recording baseline clinical, virologic and biochemical characteristics, sustained virologic response at week 12 (SVR12) and virologic failure. SVR12 outcome was based on intention to treat (ITT). Multivariate analysis was used to assess independent risk factors for SVR12 using SPSS version 20. A total of 2171 patients from India (n = 977), Myanmar (n = 552), Pakistan (n = 406), Thailand (n = 139), Singapore (n = 72) and Malaysia (n = 25) were collected. At baseline, mean age was 49 years, 50.2% were males, and 41.8% had cirrhosis. Overall, SVR12 was 89.5% and by genotype (GT) based on ITT and treatment completion, respectively, was 91% and 92% for GT1, 100% and 100% for GT2, 91% and 97% for GT3, 64% and 95% for GT4, 87% and 87% for GT6 and 79% and 91% for GT untested. Patients with cirrhosis had SVR12 of 85% vs 93% for noncirrhosis (P < 0.001) (RR 2.1, 95% CI 1.4-3.1, P = 0.0002). Patients with GT1 and GT3 treated with sofosbuvir/ribavirin (SR) had 88% and 89% SVR12, respectively, but those GT6 treated with sofosbuvir/ledipasvir (SL) had only 77.6% SVR12. Multivariate analysis showed absence of cirrhosis was associated with higher SVR12 (OR 2.0, 95% CI 1.3-3.1, P = 0.002). In conclusion, patients with GT1 and GT3 with/without cirrhosis had surprisingly high efficacy using SR, suggesting that Asians may respond better to some DAAs. However, poor GT6 response to SL suggests this regimen is suboptimal for this genotype.

Sofosbuvir/Velpatasvir for the treatment of Hepatitis C Virus infection

Hepatitis C Virus (HCV) infection is major health problem worldwide, with 150 million infected people according to recent epidemiologic estimations. The introduction of direct-acting antivirals made a revolutionary change in the management of HCV infected patients with surprisingly high rates of antiviral response, improved tolerability and reduced time of treatment. Sofosbuvir, in combination with different partner drugs, has been the molecule that led this incredible change. The last generation of SOF-based regimens, namely Sofosbuvir/Velpatasvir, represents a single tablet, once a day, pangenotypic and pan-fibrotic combination, demonstrated to be safe and effective in almost all type of HCV infected individuals. This review overviews the main clinical data of SOF/VEL registration trials, underlying the key features of this combination in terms of efficacy, safety and Patients Reported Outcomes obtained in more than 1800 HCV chronically infected subjects. (www.actabiomedica.it)

Pooled Resistance Analysis in Patients with Hepatitis C Virus Genotype 1 to 6 Infection Treated with Glecaprevir-Pibrentasvir in Phase 2 and 3 Clinical Trials

Over 2,200 patients infected with hepatitis C virus (HCV) genotypes (GT) 1 to 6, with or without cirrhosis, who were treatment naive or experienced to interferon, ribavirin, and/or sofosbuvir were treated with glecaprevir/pibrentasvir for 8, 12, or 16 weeks in eight registrational phase 2 and 3 clinical studies. High rates of sustained virologic response at 12 weeks postdosing (SVR12) were achieved with a <1% virologic failure (VF) rate. The prevalence of baseline polymorphisms (BPs) in NS3 at amino acid position 155 or 168 was low (<3%) in patients infected with GT1, GT2, GT3, GT4, and GT6, while 41.9% of the GT5-infected patients had NS3-D168E; BPs were not detected at position 156 in NS3. The prevalence of NS5A-BPs was high across genotypes, driven by common polymorphisms at amino acid position 30 or 31 in GT2, 58 in GT4, and 28 in GT6. The prevalence of NS5A T/Y93 polymorphisms was 5.5% in GT1, 4.9% in GT3, and 12.5% in GT6. Consistent with the activity of glecaprevir and pibrentasvir against most amino acid polymorphisms in vitro, BPs in NS3 and/or NS5A did not have an impact on treatment outcome for patients infected with GT1 to GT6, with the exception of treatment-experienced GT3-infected patients treated for 12 weeks, for whom a 16-week regimen of glecaprevir/pibrentasvir was required to achieve SVR12 rates of ≥95%. Among the 22 patients experiencing VF, treatment-emergent substitutions were detected in NS3 in 50% of patients and in NS5A in 82% of patients, frequently as a combination of substitutions that conferred resistance to glecaprevir and/or pibrentasvir. The glecaprevir/pibrentasvir regimen, when the recommended durations are used, allows for a pan-genotypic treatment option without the need for baseline resistance testing.

Analysis of Host and Viral-Related Factors Associated to Direct Acting Antiviral Response in Hepatitis C Virus Patients

Hepatitis C virus (HCV) signifies an important health issue as it is a globally prevalent pathogen and poses a great threat to human health. Direct antiviral therapy became a landmark in treatment against chronic HCV infection as they have proven to increase sustained virological response (SVR) rate, provide shortened and simplified regimens. This study aimed to evaluate efficacy of Sofosbuvir and classify factors of treatment success and their function in therapy continuation decision. We studied host and viral factors in 310 patients who received Sofosbuvir (DAA) at a dose of 400 mg daily along with ribavirin 10 mg/kg body weight for 24 weeks and followed by 12 weeks after completion of treatment. A total of 302 patients (97.42%) showed end-of-treatment response. However, 8 patients (2.58%) were virological nonresponders and 286 patients (94.70%) achieved SVR. Among 310 HCV positive, the percentage of viral genotype 3-infected patients was 89.6%, whereas only 10.32% were affected by HCV genotype 1. Multivariable analysis showed that baseline HCV RNA (≤8 × 10⁶ IU/mL vs. >8 × 10⁶ IU/mL) [95% confidence interval (CI), odds ratio (OR) 3.0, 2.0 to 8.4; p = 0.004], age (<50 vs. ≥50 years) (95% CI, OR 1.9, 3.0 to 10.1; p = 0.03), liver texture (normal liver vs. coarse) are related to virological response. None of the patients included in the study has S282T substitution in NS5b of HCV. No significant difference in response was observed in patients with different genotypes of rs12979860. Liver texture, age, and viral load are predictors of SVR. In this real-life data no substitution of S282T in NS5b was observed related to failure of therapy. Oral Sofosbuvir generally has a high tolerance and can effortlessly beat the safety concerns of past regimens.

Hepatitis C virus genotype 3: clinical features, current and emerging viral inhibitors, future challenges

Hepatitis C virus (HCV) represents a global burden on healthcare that affects over 150 million people worldwide. In the past, HCV genotype 3 was considered difficult to treat relative to other genotypes. Genotype 3 has been associated with a higher rate of complications, including fatty liver disease, fibrosis, hepatocellular carcinoma and mortality. However, with the advent of first- and second-generation direct-acting antivirals, genotype 3 can be treated effectively. Additionally, these new drugs are well tolerated by patients and have significantly fewer side effects compared to ribavirin and interferon-based regimens. However, while great strides have been made in overcoming biological barriers, our next challenge lies in overcoming economic and financial obstacles if we are to eradicate HCV genotype 3. Herein, we review the clinical features associated with HCV genotype 3, current and emerging treatment regimens, and challenges associated with treatment.

Ledipasvir-Sofosbuvir Plus Ribavirin in Treatment-Naive Patients With Hepatitis C Virus Genotype 3 Infection: An Open-Label Study

Background

Patients chronically infected with genotype 3 hepatitis C virus (HCV) have faster disease progression and are less responsive to current direct-acting antiviral regimens than patients infected with other genotypes. We conducted an open-label trial to evaluate the safety, tolerability, and efficacy of ledipasvir and sofosbuvir plus ribavirin in patients with genotype 3 HCV infection.

Methods

We enrolled treatment-naive patients with and without compensated cirrhosis at 15 sites in Canada. All patients were treated with ledipasvir-sofosbuvir (90 mg and 400 mg) plus weight-based ribavirin for 12 weeks. The primary endpoint was sustained virologic response 12 weeks after treatment (SVR12). Secondary endpoints included evaluation of baseline and treatment-emergent drug resistance.

Results

Of the 111 patients enrolled, 105 (95%) had subtype 3a HCV and 39 (35%) had compensated cirrhosis. SVR12 was achieved by 99 of 111 patients (89%; 95% confidence interval, 82%-94%). Of the 39 patients with cirrhosis, 31 (79%) achieved SVR12, compared with 68 of 72 (94%) patients without cirrhosis. No treatment-emergent resistance mutations occurred in those who failed treatment. One patient discontinued treatment due to liver cancer and died 22 days after treatment discontinuation. The most common adverse events were fatigue (51%), headache (36%), and nausea (23%).

Conclusions

In this multicenter trial involving treatment-naive patients with genotype 3 HCV, 12 weeks of ledipasvir-sofosbuvir provided a high level of SVR in those without cirrhosis.

Clinical Trials Registration

NCT02413593.

Impact of comorbidities on patient outcomes after interferon-free therapy-induced viral eradication in hepatitis C

BACKGROUND & AIMS

Patients with advanced liver fibrosis remain at risk of cirrhosis-related outcomes and those with severe comorbidities may not benefit from hepatitis C (HCV) eradication. We aimed to collect data on all-cause mortality and relevant clinical events within the first two years of direct-acting antiviral therapy, whilst determining the prognostic capability of a comorbidity-based model.

METHODS

This was a prospective non-interventional study, from the beginning of direct-acting antiviral therapy to the event of interest (mortality) or up to two years of follow-up, including 14 Spanish University Hospitals. Patients with HCV infection, irrespective of liver fibrosis stage, who received direct-acting antiviral therapy were used to build an estimation and a validation cohort. Comorbidity was assessed according to Charlson comorbidity and CirCom indexes.

RESULTS

A total of 3.4% (65/1,891) of individuals died within the first year, while 5.4% (102/1,891) died during the study. After adjusting for cirrhosis, platelet count, alanine aminotransferase and sex, the following factors were independently associated with one-year mortality: Charlson index (hazard ratio [HR] 1.55; 95% CI 1.29-1.86; p = 0.0001), bilirubin (HR 1.39; 95% CI 1.11-1.75; p = 0.004), age (HR 1.06 95% CI 1.02-1.11; p = 0.005), international normalized ratio (HR 3.49; 95% CI 1.36-8.97; p = 0.010), and albumin (HR 0.18; 95% CI 0.09-0.37; p = 0.0001). HepCom score showed a good calibration and discrimination (C-statistics 0.90), and was superior to the other prognostic scores (model for end-stage liver disease 0.81, Child-Pugh 0.72, CirCom 0.68) regarding one- and two-year mortality. HepCom score identified low- (≤5.7 points: 2%-3%) and high-risk (≥25 points: 56%-59%) mortality groups, both in the estimation and validation cohorts. The distribution of clinical events was similar between groups.

CONCLUSIONS

The HepCom score, a combination of Charlson comorbidity index, age, and liver function (international normalized ratio, albumin, and bilirubin) enables detection of a group at high risk of one- and two-year mortality, and relevant clinical events, after starting direct-acting antiviral therapy.

LAY SUMMARY

The prognosis of patients with severe comorbidities may not benefit from HCV viral clearance. An algorithm to decide who will benefit from the treatment is needed to manage the chronic HCV infection better.

Impact of direct acting antivirals on occurrence and recurrence of hepatocellular carcinoma: Biologically plausible or an epiphenomenon?

Hepatocellular carcinoma (HCC) is a major cause of morbidity and mortality worldwide. Chronic hepatitis C virus infection (HCV) is the most common cause of HCC in many European countries, Japan and Pakistan. Introduction of the new direct acting antivirals (DAAs) has revolutionized the management of HCV worldwide, with high rates of sustained virologic response in patients who could not have tolerated the previous interferon based treatments. However, recently there have been reports raising caution about the long term effects of DAAs, particularly a possible increased risk of HCC. Therefore this review explores the current molecular studies as well as clinical data that investigate the impact of DAAs on occurrence and recurrence of HCC.

Efficacy and safety results of patients with HCV genotype 2 or 3 infection treated with ombitasvir/paritaprevir/ritonavir and sofosbuvir with or without ribavirin (QUARTZ II-III)

The efficacy and safety of an investigational combination of ombitasvir/paritaprevir/ritonavir (OBV/PTV/r) plus sofosbuvir (SOF) ± ribavirin (RBV) in patients with HCV genotype 2 or 3 infection with or without cirrhosis was evaluated. Patients with HCV genotype 3 infection without cirrhosis were randomized to receive OBV/PTV/r + SOF ± RBV for 12 weeks; OBV/PTV/r + SOF + RBV was administered to genotype 3-infected patients with cirrhosis for 12 weeks and to genotype 2-infected patients without cirrhosis for either 6 or 8 weeks. Efficacy was assessed by sustained virologic response [HCV RNA <25 IU/mL] 12 weeks post-treatment (SVR12). Safety was assessed in all treated patients. In patients with genotype 3 infection with or without cirrhosis treated with 12 weeks of OBV/PTV/r + SOF ± RBV, the overall SVR12 rate was 98% (50/51), with no virologic failures. Patients with genotype 2 infection treated with OBV/PTV/r + SOF + RBV had SVR12 rates of 90% (9/10) and 44% (4/9) following 8- and 6-week treatment durations, respectively; failure to achieve SVR12 for these patients was due to relapse without baseline or treatment-emergent resistance-associated substitutions. Thus, the investigational combination of OBV/PTV/r with SOF ± RBV was well tolerated and achieved high SVR rates with no virologic failures in patients with genotype 3 infection. Combining direct-acting antivirals with complementary mechanisms of action and different viral targets may be an effective treatment strategy that may allow for shorter durations of therapy.

Sofosbuvir and daclatasvir therapy in patients with hepatitis C-related advanced decompensated liver disease (MELD ≥ 15)

BACKGROUND

Antiviral therapy for hepatitis C has the potential to improve liver function in patients with decompensated cirrhosis.

AIMS

To examine the virological response and effect of viral clearance in patients with decompensated hepatitis C cirrhosis all with MELD scores ≥15 following sofosbuvir/daclatasvir ± ribavirin.

METHODS

We prospectively collected data on patients who commenced sofosbuvir/daclatasvir for 24-weeks under the Australian patient supply program (TOSCAR) and analysed outcomes including sustained viral response at 12 weeks (SVR12), death and transplant.

RESULTS

108 patients (M/F, 79/29; median age 56years; Child-Pugh 10; MELD 16; genotype 1/3, 55/47) received sofosbuvir/daclatasvir and two also received ribavirin. On intention-to-treat, the SVR12 rate was 70% (76/108). Seventy-eight patients completed 24-weeks therapy. SVR12 was achieved in 56 of these patients on per-protocol-analysis (76%). SVR12 was 80% in genotype 1 compared to 69% in genotype 3. Thirty patients failed to complete therapy. In patients achieving SVR12, median MELD and Child-Pugh fell from 16(IQR15-17) to 14(12-17) and 10(9-11) to 8(7-9), respectively (P<.001). In those who died, MELD increased from 16 to 23 at death (P=.036). Patients who required transplantation had a significantly higher baseline MELD (20) compared to those patients completing treatment (16) (P=.0010). The odds ratio for transplant in patients with baseline MELD ≥20 was 13.8(95%CI 2.78-69.04).

CONCLUSIONS

SVR12 rates with sofosbuvir/daclatasvir in advanced liver disease are lower than in compensated disease. Although treatment improves MELD and Child-Pugh in most patients, a significant proportion will die or require transplantation. In those with MELD ≥20, it may be better to delay treatment until post-transplant.

Glecaprevir-Pibrentasvir for 8 or 12 Weeks in HCV Genotype 1 or 3 Infection

BACKGROUND

Glecaprevir and pibrentasvir are direct-acting antiviral agents with pangenotypic activity and a high barrier to resistance. We evaluated the efficacy and safety of 8-week and 12-week courses of treatment with 300 mg of glecaprevir plus 120 mg of pibrentasvir in patients without cirrhosis who had hepatitis C virus (HCV) genotype 1 or 3 infection.

METHODS

We conducted two phase 3, randomized, open-label, multicenter trials. Patients with genotype 1 infection were randomly assigned in a 1:1 ratio to receive once-daily glecaprevir-pibrentasvir for either 8 or 12 weeks. Patients with genotype 3 infection were randomly assigned in a 2:1 ratio to receive 12 weeks of treatment with either glecaprevir-pibrentasvir or sofosbuvir-daclatasvir. Additional patients with genotype 3 infection were subsequently enrolled and nonrandomly assigned to receive 8 weeks of treatment with glecaprevir-pibrentasvir. The primary end point was the rate of sustained virologic response 12 weeks after the end of treatment.

RESULTS

In total, 1208 patients were treated. The rate of sustained virologic response at 12 weeks among genotype 1-infected patients was 99.1% (95% confidence interval [CI], 98 to 100) in the 8-week group and 99.7% (95% CI, 99 to 100) in the 12-week group. Genotype 3-infected patients who were treated for 12 weeks had a rate of sustained virologic response at 12 weeks of 95% (95% CI, 93 to 98; 222 of 233 patients) with glecaprevir-pibrentasvir and 97% (95% CI, 93 to 99.9; 111 of 115) with sofosbuvir-daclatasvir; 8 weeks of treatment with glecaprevir-pibrentasvir yielded a rate of 95% (95% CI, 91 to 98; 149 of 157 patients). Adverse events led to discontinuation of treatment in no more than 1% of patients in any treatment group.

CONCLUSIONS

Once-daily treatment with glecaprevir-pibrentasvir for either 8 weeks or 12 weeks achieved high rates of sustained virologic response among patients with HCV genotype 1 or 3 infection who did not have cirrhosis. (Funded by AbbVie; ENDURANCE-1 and ENDURANCE-3 ClinicalTrials.gov numbers, NCT02604017 and NCT02640157 .).

Global elimination of hepatitis C virus infection: Progresses and the remaining challenges

Today, with the introduction of interferon-free direct-acting antivirals and outstanding progresses in the prevention, diagnosis and treatment of hepatitis C virus (HCV) infection, the elimination of HCV infection seems more achievable. A further challenge is continued transmission of HCV infection in high-risk population specially injecting drug users (IDUs) as the major reservoir of HCV infection. Considering the fact that most of these infections remain undiagnosed, unidentified HCV-infected IDUs are potential sources for the rapid spread of HCV in the community. The continuous increase in the number of IDUs along with the rising prevalence of HCV infection among young IDUs is harbinger of a forthcoming public health dilemma, presenting a serious challenge to control transmission of HCV infection. Even the changes in HCV genotype distribution attributed to injecting drug use confirm this issue. These circumstances create a strong demand for timely diagnosis and proper treatment of HCV-infected patients through risk-based screening to mitigate the risk of HCV transmission in the IDUs community and, consequently, in the society. Meanwhile, raising general awareness of HCV infection, diagnosis and treatment through public education should be the core activity of any harm reduction intervention, as the root cause of failure in control of HCV infection has been lack of awareness among young drug takers. In addition, effective prevention, comprehensive screening programs with a specific focus on high-risk population, accessibility to the new anti-HCV treatment regimens and public education should be considered as the top priorities of any health policy decision to eliminate HCV infection.

Effectiveness of current and future regimens for treating genotype 3 hepatitis C virus infection: a large-scale systematic review

BACKGROUND

Six distinct genetic variants (genotypes 1 - 6) of hepatitis C virus (HCV) exist globally. Certain genotypes are more prevalent in particular countries or regions than in others but, globally, genotype 3 (GT3) is the second most common. Patients infected with HCV GT1, 2, 4, 5 or 6 recover to a greater extent, as measured by sustained virological response (SVR), following treatment with regimens based on direct-acting antivirals (DAAs) than after treatment with older regimens based on pegylated interferon (Peg-IFN). GT3, however, is regarded as being more difficult to treat as it is a relatively aggressive genotype, associated with greater liver damage and cancer risk; some subgroups of patients with GT3 infection are less responsive to current licensed DAA treatments. Newer DAAs have become available or are in development.

METHODS

According to PRISMA guidance, we conducted a systematic review (and descriptive statistical analysis) of data in the public domain from relevant clinical trial or observational (real-world) study publications within a 5-year period (February 2011 to May 2016) identified by PubMed, Medline In-Process, and Embase searches. This was supplemented with a search of five non-indexed literature sources, comprising annual conferences of the AASLD, APASL, CROI, EASL, and WHO, restricted to a 1-year period (April 2015 to May 2016).

RESULTS

Of the all-oral regimens, the efficacy (SVR12 ≥ 90%) of sofosbuvir plus daclatasvir- and velpatasvir-based regimens in clinical trials supports and reinforces their recommendation by guidelines. Other promising regimens comprise grazoprevir + elbasvir + sofosbuvir, and ombitasvir + paritaprevir/ribavirin + sofosbuvir. Newer regimens incorporating pibrentasvir + glecaprevir or grazoprevir + ruzasvir + MK-3682 (uprifosbuvir), offer all-oral, ribavirin-free SVR12 rates consistently greater than 95%. Observational studies report slightly lower overall SVR rates but reflect corresponding clinical trial data in terms of treatments most likely to achieve good responses.

CONCLUSIONS

On the basis of SVR12, we established that for treating GT3 infections (i) regimens incorporating newer DAAs are more effective than those comprising older DAAs, and (ii) ribavirin may be of less benefit in newer DAA regimens than in older DAA regimens. The analysis provides evidence that DAA regimens can replace Peg-IFN-based regimens for GT3 infection.

A Closing Chapter: Hepatitis C Genotype 3 Elimination in Liver Transplant; Sofosbuvir/Daclatasvir in a Hard-to-Treat Population

OBJECTIVES

Historically, hepatitis C virus genotype 3 infection has not been as hard to treat as genotype 1 using interferon-based therapy. Now, genotype 3 infection can be treated using interferon-free regimes such as the combination of sofosbuvir and daclatasvir, which is a highly successful and reliable therapeutic option before liver transplant. However, real world data are rather limited regarding the use of antivirals (sofosbuvir/daclatasvir) for hepatitis C virus genotype 3 recurrence after liver transplant. Here, we present the results of antiviral treatment with sofosbuvir and daclatasvir in patients with genotype 3 recurrence after liver transplant and also viewed published data, to finally close the chapter on genotype 3 elimination.

MATERIALS AND METHODS

We analyzed 11 patients who received liver transplants due to hepatitis C virus genotype 3-associated cirrhosis at our center. Two patients were nadve for any antiviral therapy. All patients received antiviral treatment with sofosbuvir/daclatasvir for 12 weeks after liver transplant, with 1 patient also having ribavirin. The endpoint was hepatitis C virus RNA-free survival after 12 weeks of therapy. Secondary endpoints were preservation of renal and liver function and incidence of adverse events.

RESULTS

All patients were free of hepatitis C virus RNA by at least 8 weeks after therapy initiation. Elevated transaminases and gamma-glutamyltransferase at the beginning of therapy normalized quickly during treatment. Synthesis and excretion were stable at all dates. Patients displayed no severe adverse effects, especially regarding renal function and blood counts. Sustained virologic response rates at week 12 were achieved in all 11 patients.

CONCLUSIONS

Hepatitis C virus could be eliminated in all patients after liver transplant with 12-week sofosbuvir/daclatasvir therapy. Sofosbuvir combined with daclatasvir is safe and reliable for recurrent hepatitis C virus genotype 3 infection. Our results have closed the chapter on genotype 3 recurrence after liver transplant in our outpatient clinic.

Peginterferon still has a place in the treatment of hepatitis C caused by genotype 3 virus

Despite recent advances in therapy for chronic hepatitis C (CHC), the disease caused by genotype 3 virus (GEN3) is still considered a treatment challenge in certain patient subgroups. The aim of this retrospective study was to evaluate the effectiveness and safety of the peginterferon (Peg-IFN) and ribavirin (RBV) combination treatment for GEN3/CHC patients, and to evaluate sustained virological response (SVR) indicators and early treatment interruption due to serious adverse events (SAE). This was a retrospective observational study of GEN3/CHC patients, co-infected or not by HIV and treated with Peg-IFN/RBV in nine Brazilian healthcare centers. The study sample included 184 GEN3/CHC patients; 70 (38%) were co-infected with HIV. The overall SVR rate was 57.1% (95% CI 50-64). Among co-infected and mono-infected patients, the SVR rate was 51.4% (36/70) and 60.5% (69/114), respectively (p=0.241). Thirty-four (18.5%) patients experienced SAE and interrupted treatment. SVR was negatively associated with the use of Peg-IFN alpha 2b (PR 0.75; 95% CI 0.58-0.99; p=0.045) and to early treatment interruption due to SAE (PR 0.36; 95% CI 0.20-0.68; p=0.001). Early treatment interruption due to SAE was associated with age (PR 1.06; 95% CI 1.02-1.10; p<0.001) and occurrence of liver cirrhosis (PR 2.06; 95% CI 1.11-3.83; p=0.022). In conclusion, Peg-IFN/RBV might represent an adequate treatment option, mainly in young patients without advanced liver disease or when the use of direct-action drugs is limited to specific patient groups.

Safety and efficacy of sofosbuvir-based direct-acting antiviral regimens for hepatitis C virus genotypes 1-4 and 6 in Myanmar: Real-world experience

This open-label, clinical experience investigated the safety and efficacy of direct-acting antiviral (DAA) hepatitis C virus (HCV) therapy in Myanmar; 344 patients completed treatment between June 2015 and May 2016. Patients with HCV genotypes 1-4 and 6 received one of four treatments: (i) Peg-interferon (PEG-IFN)+sofosbuvir (SOF)+ribavirin (RBV) for 12 weeks, (ii) SOF+RBV for 24 weeks, (iii) ledipasvir (LDV)+SOF for 12 weeks or (iv) daclatasvir (DCV)+SOF+RBV for 12 or 24 weeks. Genotype 3 was most common (n=133, 38.7%), followed by genotype 6 (n=122, 35.5%) and genotype 1 (n=86, 25%). Overall, 91% of patients achieved sustained virologic response (SVR); 99% in group 1, (n=148/149), 90% in group 2 (n=95/106), 78% in group 3 (n=65/83) and 100% in group 4 (n=6/6). In group 3, SVR rates were 96.8% in genotype 1 (n=30/31) and 64.1% in genotype 6 (n=25/39). Multivariable regression analysis identified advanced fibrosis (F3-4) (OR=.16 CI: 0.05-0.57, P=.005), genotype 6 (OR=.35, CI: 0.16-0.79, P=.012) and diabetes (OR=.29, CI: 0.12-0.71, P=.007) as negative independent predictors of response. Adverse events were mild with all-oral therapy.

CONCLUSION

DAA therapy ±PEG-IFN achieved high SVR rates. Genotype 6 patients had a low SVR to 12 weeks of LDV and SOF raising the need for other regimens, RBV or longer treatment duration in this population.

Younger trend of cirrhosis incidence in genotype 3 HCV infected patients in Eastern China

The diversity of HCV genotypes is ever-evolving and requires continuous surveillance. The aim of this study was to investigate the dynamics of HCV genotypes, and their associated demographic and clinical patterns in China. By searching computerized hospital information system, a total of 1155 HCV-positive patients eligible for analysis were retrospectively identified from 12 380 consecutive in-patients in the Department of Infectious Diseases, Ruijin Hospital in China between 2009 and 2014. The percentages of HCV genotype 1, 2, 3, or 6 were 61.3%, 12.8%, 18.5%, or 7.4%, respectively. The number of patients hospitalized for HCV infection increased gradually over the study period, particularly those infected by genotype 3 HCV. Patients of genotype 1, 2, 3, or 6 were significantly different. Genotype 1 or two patients were much older, with higher proportion of blood transfusion history. In contrast, genotype 3 or six patients were younger, predominantly male, with more exposure to intravenous drug use. The cirrhosis incidence was higher in genotype 1 or two patients, followed by genotype 3 and six patients. Strikingly, genotype 3 cirrhotic patients were younger, and their estimated infection durations were also shorter, suggestive of a faster disease progression in genotype 3 patients. Multivariate analysis demonstrated that presence of HBcAb was an independent predictor of cirrhosis (OR 2.19, 95%CI 1.27-3.42; P = 0.004). The leading increase and the younger trend of cirrhosis incidence in genotype 3 patients argue for a higher priority to manage the infection in this highly at-risk population.

Efficacy of 12 or 18 weeks of elbasvir plus grazoprevir with ribavirin in treatment-naïve, noncirrhotic HCV genotype 3-infected patients

Elbasvir (EBR; HCV NS5A inhibitor) and grazoprevir (GZR; HCV NS3/4A protease inhibitor) are approved as a fixed-dose combination to treat patients chronically infected with HCV genotypes 1 and 4. During the development programme and supported by in vitro potency, the efficacy of EBR+GZR was assessed in HCV GT3-infected patients. This study's aim was to determine the efficacy and tolerability of 12 or 18 weeks of EBR+GZR with ribavirin (RBV) in treatment-naïve, noncirrhotic HCV GT3-infected patients. Randomized patients received open-label EBR (50 mg once daily) + GZR (100 mg once daily) + RBV. The primary efficacy objective was to evaluate the sustained virologic response rates 12 weeks after the end of all study therapy (SVR12). SVR12 rates (95% confidence interval) were 45.0% (23.1, 68.5) and 57.1% (34.0, 78.2) after treatment with EBR+GZR+RBV for 12 weeks or 18 weeks, respectively. On-treatment virologic failure was observed in 41% (17 of 41) of patients. At virologic failure, resistance-associated substitutions (RASs) with a >five-fold shift in potency occurred in the NS3 region in six (35%) patients and in the NS5A region in 16 (94%) patients. The most common RAS at virologic failure was Y93H in NS5A which was identified in 13 of 17 (76%) patients. The efficacy of EBR+GZR+RBV was suboptimal in HCV GT3-infected patients due to a high rate of on-treatment virologic failure and treatment-emergent RASs which demonstrates an inadequate barrier to the development of GT3 resistance. However, rapid viral clearance demonstrated the antiviral activity of EBR+GZR+RBV in GT3-infected patients.clinicaltrials.gov: NCT01717326.

Direct-acting antiviral agents against hepatitis C virus and lipid metabolism

Hepatitis C virus (HCV) infection induces steatosis and is accompanied by multiple metabolic alterations including hyperuricemia, reversible hypocholesterolemia and insulin resistance. Total cholesterol, low-density lipoprotein-cholesterol and triglyceride levels are increased by peginterferon and ribavirin combination therapy when a sustained virologic response (SVR) is achieved in patients with HCV. Steatosis is significantly more common in patients with HCV genotype 3 but interferon-free regimens are not always effective for treating HCV genotype 3 infections. HCV infection increases fatty acid synthase levels, resulting in the accumulation of fatty acids in hepatocytes. Of note, low-density lipoprotein receptor, scavenger receptor class B type I and Niemann-Pick C1-like 1 proteins are candidate receptors that may be involved in HCV. They are also required for the uptake of cholesterol from the external environment of hepatocytes. Among HCV-infected patients with or without human immunodeficiency virus infection, changes in serum lipid profiles are observed during interferon-free treatment and after the achievement of an SVR. It is evident that HCV affects cholesterol metabolism during interferon-free regimens. Although higher SVR rates were achieved with interferon-free treatment of HCV, special attention must also be paid to unexpected adverse events based on host metabolic changes including hyperlipidemia.