How to optimize HCV therapy in genotype 2 patients

Circulating Genotypes of Hepatitis C Virus in Italian Patients before and after the Application of Wider Access Criteria to HCV Treatment

Aims:

The aims of this study were to report a description of the HCV genotype distribution in adult Italians and non-Italians subjects tested in the Microbiology and Virology Unit of the Padova University Hospital from January 2016 (after about one year from the availability of DAAs) to December 2018 and to compare genotype frequencies in the 12-month period before and after the application of the wider access criteria to HCV treatment.

Background:

Hepatitis C virus (HCV) infection is a major health problem, but the availability of direct-acting antivirals (DAAs) has dramatically changed HCV disease natural history because these drugs have excellent tolerability and they can eliminate the virus in almost all treated patients.

Objective:

The objective was to describe the circulating HCV genotypes in high-income countries in order to help health authorities in the future organization of DAAs treatment strategies; this aspect is not limited to drug prescription, but it also includes the identification of infected individuals who are undiagnosed, which is the limiting step to achieve the HCV elimination goal.

Methods:

Adult patients who had HCV genotype performed from 01/01/16 to 31/12/18 in the Microbiology and Virology Unit of the Padova University Hospital were included in the study: the two 12-month periods were April 2016-March 2017 (before period, BEF) and April 2017-March 2018 (after period, AFT).

Results:

Italians were 2168 (91.2%) and non-Italians were 208 (8.8%). Italians median age was 55 years, and females were older. Italians had a lower genotype 1 (p=0.0012) and higher genotype 2 frequencies (p<0.0001) with respect to non-Italians. Most patients aged 38-67 years: Italians were more represented in class age 48-57 years (p=0.0138), 68-77 years (p=0.001) and ≥78 years (p<0.0001); subjects with genotype 3 were the youngest and those with genotype 2 the oldest. Italian patients typed in the AFT and BEF were comparable; only a lower frequency of genotype 1 males and younger age in genotype 3 were found in AFT.

Conclusion:

Italians were older with respect to non-Italians, which implies that a different age based screening program could be applied. Italian genotype 3 subjects represent a cohort to focus on for the risk of therapeutic failure. Patients tested after the extended criteria for HCV treatment were very similar to those tested before, suggesting that HCV burden in Italians is higher than expected.

Hepatitis C Virus Subtype and Evolution Characteristic Among Drug Users, Men Who Have Sex With Men, and the General Population in Beijing, China

The aim of this study was to characterize the current molecular epidemiology of hepatitis C virus (HCV) infection and evaluate the evolutionary patterns of HCV subtypes in Beijing, China, among different subpopulations.The whole blood samples and behavioral data were collected from a total of 10,354 subjects, including drug users (DUs), men who have sex with men (MSM), and the general population, in Beijing from 2010 to 2011. Samples were tested for HCV infection using both enzyme-linked immunosorbent assay (ELISA) and real-time PCR. All viremic subjects were then sequenced by nested PCR over core/E1 and NS5B regions. Phylogenetic and phylogeographic analysis was performed by BEAST software.In total, 217 subjects (2.1%) were tested positive for HCV by antibody or vRNA-based testing. HCV prevalence rates for DUs, MSM, and the general population were 26.2%, 0.54%, and 0.37%, respectively. The 156 HCV RNA-positive samples were sequenced. Nine HCV genotypes, including 1a, 1b, 2a, 3a, 3b, 6a, 6n, 6u and 6v, were detected. The most prevalent subtypes were 3b (36.09%), 1b (32.54%), and 3a (16.57%). Bayesian evolutionary analysis estimated that the time of introduction of subtype 1b into Beijing was 2004 (95% CI: 1997.7, 2007.7), with subtypes 3a and 3b being introduced later in 2006. Evolutionary analyses further suggested that subtype 1b from Beijing and Shanghai were closely related, whereas subtype 3a sequences were more similar with sequences from Yunnan, Guangzhou, Hong Kong, and Jiangsu. Subtype 3b sequences were closely related to those from Yunnan, Guangdong, and Hong Kong.Thus, the current HCV epidemic in Beijing is complex, heavily affecting DUs, and involving multiple genotypes that likely spread from different regions in China with its large migrant population.

Phylogenetic analysis of HCV subgenotypes in patients from Sichuan province in China based on the NS5B region

The classification of hepatitis C virus (HCV) genotypes is of clinical importance as it may help to predict drug therapy responses and estimate treatment duration. The classical method of HCV subgenotype classification is whole genome sequencing (WGS). However, the high cost and time-consuming nature of WGS limits its usage in clinical practice. A number of studies have been conducted to confirm whether specific regions of HCV could replace WGS in the classification of HCV subgenotypes. In the present study, we used the HCV database to select HCV sequences from different countries. The neighbor-joining method was used to construct phylogenetic trees based on different regions of HCV (core, E1, E2 and NS5B), to confirm which region could replace WGS in subgenotype classification. Our results indicated that the core, E1 and E2 regions could not be used to classify the HCV subgenotype correctly (core failed to recognize subgenotypes c and a, E1 failed to discriminate between subgenotypes a and b, and E2 failed to identify subgenotypes a and c). The NS5B region provided the correct subgenotype classification. The HCV samples (n=153) collected from patients in Sichuan province, (Southwest China) were sequenced and classified based on the NS5B region. The results indicated that the major subgenotype of HCV in patients from Sichuan was 1b (51.6%, n=79); other subgenotypes included 3b (30.1%, n=46), 3a (7.8%, n=12), 6a (8.5%, n=13), 2a (n=2) and 6n (n=1). The data from our analysis may prove to be helpful in future epidemiological investigations of HCV, and may aid in the prevention and clinical treatment of HCV.

Update on the treatment of hepatitis C genotypes 2-6

PURPOSE OF REVIEW

The hepatitis C virus remains a global health issue, and the established standard of care has consisted of pegylated interferon alpha in conjunction with ribavirin. However, this regimen is associated with significant side-effects and poor sustained virological responses. The aim of this review is to assess the effects of the direct-acting antivirals upon hepatitis C genotypes 2-6 from publications from the past 18 months.

RECENT FINDINGS

The impact of direct-acting antivirals has already substantially improved treatments for genotypes 2-6, with the size of improvement much less marked for genotype 3. Although still responsive to these agents, genotype 3 has inherent resistance to treatments possibly owing to its effects on host metabolic pathways. These treatments have moved sustained virological responses to the threshold of 90%, with reduced side-effects and shortened courses of treatment and some options for interferon-free therapy. These newer medications are transforming clinical guidelines at a rapid rate, but this will have to be balanced with the impact it places on global health budgets.

SUMMARY

Although direct-acting antivirals are transforming the treatment of all hepatitis C genotypes, ongoing studies will optimize treatment duration and provide interferon-free alternatives.

Increased prevalence of hepatitis C virus subtype 6a in China: a comparison between 2004-2007 and 2008-2011

Different hepatitis C virus (HCV) genotypes exhibit differences in disease pathogenesis and progression, as well as disease outcomes and response to therapy. Tracking the change of HCV genotypes in various epidemiological settings is critical for both disease surveillance and the development of improved antiviral treatment. Here, we tracked the changes in the prevalence of the HCV genotypes in China between 2004-2007 and 2008-2011. HCV-RNA-positive sera were collected from volunteer blood donors during the period 2008-2011. The genotypes were determined by phylogenic analysis using the NS5B and E1 sequences. Geographical and demographic distribution patterns related to the HCV genotypes obtained in 2008-2011 were compared with our previous study, which recorded data in the period 2004-2007. Pearson chi-square test and t-test were used to statistically analyze the results. In 2008-2011, HCV subtypes 1b and 6a were detected in 43.8 % (184/420) and 34.3 % (144/420), respectively. The male/female ratio was found to be higher for HCV genotype 6 than for genotypes 1 and 2. When compared with the period of 2004-2007, although no significant difference was found in gender or age for genotypes 1, 2, 3 and 6, the subtype 6a frequency was significantly increased from 11 % to 26.5 % in the blood donors from outside of Guangdong Province in 2008-2011. A pattern of increase in HCV subtype 6a was found in blood donors outside of Guangdong Province, indicating that HCV subtype 6a has rapidly spread from Guangdong to other regions of China over the past 10 years.

Hepatitis C in Argentina: epidemiology and treatment

Hepatitis C is the leading cause of chronic hepatitis, cirrhosis, and liver cancer in Argentina, where from 1.5% to 2.5% of adults are infected. Most of the infections were acquired 30-50 years ago. It is estimated that more than half of infected individuals are not aware of their infection. Even though the prevalence in blood donors has decreased to 0.45% at present, many high-prevalence populations still exist, where the reported prevalence ranges from 2.2% to 7.1%. Therapy is recommended for patients with fibrosis, in order to prevent disease progression, hepatic decompensation, and hepatocellular carcinoma. Great advances were achieved in the treatment of genotype 1 infection since the development and release of boceprevir and telaprevir. When either of these protease inhibitors is associated with peginterferon plus ribavirin, the sustained virological response (SVR) rate improves from 40%-50% to 67%-75%. For genotype 2 and 3 infection, treatment with peginterferon plus ribavirin is still the standard of care, with SVR rates of 70%-90%. There are significant new antivirals in development, and some of them are close to being released. These drugs will most likely be the future standard of care for all genotypes, and will be incorporated in better-tolerated and highly effective all-oral regimes. The impact that these new therapies might have in health-related economics is unpredictable, especially in developing countries. Each country must carefully evaluate the local situation in order to implement proper screening and treatment programs. Difficult-to-treat patients, such as those with decompensated cirrhosis, patients in hemodialysis, and those with other significant comorbidities, might not be able to receive these new therapeutic approaches and their management will remain challenging.

The "hidden" epidemic: a snapshot of Moroccan intravenous drug users

Background

Hepatitis C virus is a persistent epidemiological problem, with an estimated 170 million individuals infected worldwide, and the leading cause of asymptomatic chronic infection, liver cirrhosis and hepatocellular carcinoma. Injection drug users (IDUs) have the highest seroprevalence as compared to chronic hemodialysis and transfusion patients, and this cohort remains the most under-studied high-risk group in North Africa to date. This study first sought to characterize the demographic, epidemiological, and genotypic profile of a total sample size of 211 chronically-infected IDUs living in the Tangier region of Northern Morocco, and secondly to contrast this to other chronically-infected patients, in order to uncover possible discrepancies.

Results

The general ‘profile’ of local IDUs marks a stark contrast to chronically-infected HCV Moroccan patients, other African countries, and neighboring European countries. The majority of Moroccan drug users were found to be middle-aged and celibate. A relatively high seroprevalence was found among drug users (60%), and this increased with age. The majority of drug users shared their needles and this hold implications for transmission, as seropositive status was significantly different between those users that shared vs. those that did not share their needles. In addition, IDUs exhibited genotypes 1a and 3a predominantly, as compared to the predominant 1b and 2a/2c genotypes found in chronically HCV-infected patients. The IDU genotypic profile closely matches the one in other European countries (Portugal, Spain, France, and Italy), which are invariably speculated as the potential source of currently-circulating genotypes in Moroccan IDUs.

Conclusion

These findings have implications for disease prevention, transmission and treatment, as this distinct IDU subgroup cannot be collectively pooled along with other HCV-positive high-risk groups. Local government, practitioners, and health institutions should take this into account when treating, prescribing antiviral therapy, and designing preventative public health campaigns.

How to optimize current treatment of genotype 2 hepatitis C virus infection

The standard of care (SOC) for hepatitis C virus (HCV) genotype 2 is pegylated interferon (PEG-IFN) plus ribavirin (RBV). Even though most patients can be cured with this therapy after 24 weeks, tailoring treatment can improve its safety and efficacy in special populations. Thus, shortening treatment together with a weight-based RBV dosing approach has been considered satisfactory in patients with positive predictors of response. With the development of the direct antiviral agents (DAAs), shorter, better tolerated and more efficient treatments for HCV genotype 2 will become available, including interferon-free regimens. Until these new treatments are released, the decision to treat patients with HCV genotype 2 with currently approved drugs or to wait for future options must be made, taking into account the stage of fibrosis.

Discovery and preclinical characterization of the cyclopropylindolobenzazepine BMS-791325, a potent allosteric inhibitor of the hepatitis C virus NS5B polymerase

Described herein are structure-activity relationship studies that resulted in the optimization of the activity of members of a class of cyclopropyl-fused indolobenzazepine HCV NS5B polymerase inhibitors. Subsequent iterations of analogue design and syntheses successfully addressed off-target activities, most notably human pregnane X receptor (hPXR) transactivation, and led to significant improvements in the physicochemical properties of lead compounds. Those analogues exhibiting improved solubility and membrane permeability were shown to have notably enhanced pharmacokinetic profiles. Additionally, a series of alkyl bridged piperazine carboxamides was identified as being of particular interest, and from which the compound BMS-791325 (2) was found to have distinguishing antiviral, safety, and pharmacokinetic properties that resulted in its selection for clinical evaluation.

Analysis of hepatitis C virus subgenotypes in patients in Heilongjiang province

AIM: To analyze the distribution of different hepatitis C virus (HCV) subgenotypes in Heilongjiang province, China.

METHODS: Serum samples from 1 313 patients with HCV infection, including 627 (47.75%) males and 686 (52.25%) females, were subgenotyped using multiplex nested PCR assay. The associations of HCV subgenotypes with gender, age, viral load, and ALT level were analyzed.

RESULTS: Of 1 313 patients, 927 (70.60%) were successfully subgenotyped. Among typable subgenotypes, 1b⁺/2a^- was found in 388 (41.86%) cases, 2a⁺/1b^- in 318 (34.30%) cases, 1b+2a in 197 (21.25%) cases, and 1a+/2b in 24 (2.59%) cases. The percentage of patients with 2a⁺/1b^- subgenotype was significantly higher in females (37.50%) and patients with HCVRNA of (1.000-9.999) × 10⁴ (54.55%), ALT level >200 (60.87%) or ≤ 40 (41.02%) (all P < 0.05). The percentage of patients with 1b⁺/2a^- subgenotype was significantly lower in patients with HCVRNA of (1.000-9.999) × 10⁴ (24.24%) or ALT level >200 (13.04%) (both P < 0.05).

CONCLUSION: Genotypes 1b and 2a are the most prevalent genotypes in Heilongjiang province. The distribution of different HCV subgenotypes is associated with gender, viral load, and ALT level.