World-wide Prevalence of Substitutions in HCV Genome Associated With Resistance to Direct-Acting Antiviral Agents

Resistance-Associated Substitution Testing Trends and Impact on HCV Treatment Outcomes in Canada: A CanHepC-CANUHC Analysis

Resistance-associated substitutions (RASs) are mutations within the hepatitis C (HCV) genome that may influence the likelihood of achieving a sustained virological response (SVR) with direct acting antiviral (DAA) treatment. Clinicians conduct RAS testing to adapt treatment regimens with the intent of improving the likelihood of cure. The Canadian Network Undertaking against Hepatitis C (CANUHC) prospective cohort consists of chronic HCV patients enrolled between 2015 and 2023 across 17 Canadian sites. Utilisation of RAS testing was assessed across demographics, clinical characteristics and years. SVR was described for the overall cohort and compared across populations of patients with historically negative predictors of SVR. The detection of key RASs and how this information influenced DAA selection were assessed. 2434 patients were identified with information on RAS testing. 98.3% achieved SVR. Out of the 227 patients tested for RAS, 147 (64.8%) had any detected RAS, and 84 (37.0%) had an NS5A RAS. The proportion of patients with SVR did not differ between RAS-tested (98.3%) and non-tested patients (98.3%; p = 0.99). SVR in those with an NS5a RAS was similar (98.6%) to the overall SVR proportion. Proportions with SVR did not differ between those with and without RAS testing in key subgroups (genotype 1a, genotype 3, prior treatment, cirrhosis). The specific DAA regimen and the addition of ribavirin were not associated with SVR outcome. RAS testing has a minimal influence on antiviral treatment selection. Going forward, there is a reduced role for RAS testing in most clinical scenarios.

Prevalence and drug resistance analysis of hepatitis C virus genotypes in Heilongjiang, China

Hepatitis C still poses a threat to public safety, and there are few reports of hepatitis C virus (HCV) in Heilongjiang Province. Therefore, we aimed to study the epidemiology and resistance-associated substitutions (RASs) of HCV in Heilongjiang and explore the efficacy of treatment. 7019 specimens from Heilongjiang Province were subjected to the genotype identification. The Autoregressive Integrated Moving Average (ARIMA) model was utilized to predict HCV infection trends from 2024 to 2030. The Sanger sequencing was performed on samples of genotype(GT) 1b and 2a to investigate RASs. Phylogenetic analysis was conducted to assess the similarity of local HCV sequences with those from other countries. In addition, we tracked the effect of patients treated with DAAs and the relationship between efficacy and RASs. The predominant HCV subtypes in Heilongjiang were 1b (47.51 %) and 2a (43.85 %). From 2012 to 2023, the proportions of GT2a, GT3a, GT3b, and GT6a gradually increased. And the prevalence of GT2a will exceed that of GT1b over the next seven years. The proportion of RASs in GT1b and GT2a NS5A region was 73.47 % and 15.22 %, respectively. And the proportion of RASs in GT1b NS5B region was 100 %. Local HCV sequences exhibited phylogenetic relationships with sequences from other countries. The GT1b R30Q and GT2a C92S were correlated with drug efficacy. K107R and P206S, which have not been reported in the literature, were also related to drug efficacy. The epidemiology of HCV genotypes in Heilongjiang is becoming increasingly diverse. HCV GT1b has a large variety and a high proportion of RASs, and patients infected with this genotype of HCV need to be sequenced before treatment.

Study of drug resistance-associated genetic mutations, and phylo-genetic analysis of HCV in the Province of Sindh, Pakistan

Current management of HCV infection is based on Direct-Acting Antiviral Drugs (DAAs). However, resistance-associated mutations, especially in the NS3 and NS5B regions are gradually decreasing the efficacy of DAAs. The aim of the current study was to identify such mutations in the NS3, and NS5B genes in DAAs treatment-naïve Pakistani chronic HCV 3a patients. Peripheral blood samples were collected from 233 chronic HCV 3a patients at different tertiary care hospitals in Karachi, Pakistan, between August 2020 to September 2021. PCR-amplified target regions of the NS3/NS5B gene were subjected to Sanger sequencing to identify resistance-associated mutations. Phylogenetic analysis of the identified amino acid sequences was performed using HCV3a sequences of the global population in the virus pathogen resource (VIPR) database. Sequence analysis identified five amino acid mutations, Leu36Pro, Gln41His, Gln80Lys/Arg, Ala156Tyr, and Gln168Arg in the NS3 region, and two mutations Leu159Phe and Cys316Arg in the NS5B region. Phylogenetic analysis revealed a high genetic diversity in the studied isolates. Overall, the prevalence of resistance-associated substitutions was almost similar to other geographic regions worldwide. This data could be helpful in selecting the most effective treatment regimen for HCV chronically infected people in Pakistan.

Resistant-Associated Substitutions Do Not Affect HCV RNA and HCV Core Antigen Clearance During Direct-Acting Antiviral Agent Treatment in a Real-World Setting

Background

Since oral direct-acting antiviral agents (DAAs) became available, the global hepatitis C treatment situation has undergone tremendous changes. However there are still many issues worthy of attention in treatment.

Methods

We selected 53 HCV-infected patients who were treated and followed up in the Peking University First Hospital from December 2017 to January 2021 to detect the RASs in HCV. Pearson correlation analysis was used to analyze HCV RNA and HCV cAg, the Fisher exact test and chi-square test was used to compare the effects of RASs on the rate of decline of HCV RNA and HCV core antigen (cAg) during DAA treatment.

Results

The RASs and its prevalence on the NS3 are mainly Y56F 2.56% (1/39), Q80K 23.08% (9/39), S122G 71.79% (28/39), and V170I 38.46% (15/39). On the NS5A were R30Q 10.53% (4/38), P32A 5.26% (2/38), P58S 2.63% (1/39), and Y93H 21.05% (8/38). On NS5B were C316N 71.05% (27/38), C451H 2.63% (1/38), and I585C 2.63% (1/38). There was no significant correlation between the RASs (Y93H, V179I, Q80K, S122G, C316N) and HCV genotype (p > 0.05). The baseline serum HCV RNA and HCV cAg had a significant medium-degree correlation (r = 0.601, p = 0.002). After 1 week of DAA treatment was weak correlation (r = 0.413, p = 0.032). Q80K, S122G, V170I, Y93H, and C316N had no effect on the clearance of HCV RNA and HCV cAg within the first week of DAA treatment (p>0.05).

Conclusion

The HCV genotype may have a limited impact on the presence of the five RASs (Y93H, V179I, Q80K, S122G, and C316N) as shown in this study. HCV RNA and HCV cAg have a correlation, especially at baseline is the highest; the appearance of some RASs has no effect on DAA treatment in most chronic hepatitis C patients.

Prevalence of Naturally Occurring Resistance Associated Substitutions in NS3/4A Protease Inhibitors in Iranian HCV/HIV Infected Patients

BACKGROUND

Hepatitis C virus (HCV) acts in host as a complicated mixture of related variants with the potency to genetically escape host immune responses. Direct acting antivirals (DAAs) have been approved for HCV treatment with shorter duration, better cure rates and lower side effects. However, naturally occurring resistance associated substitutions(RASs) make some obstacles to this antiviral therapy success.

OBJECTIVE

In this study, we aimed at determination of the naturally occurring NS3/4A RASs in HCV/human immunodeficiency virus (HIV)infected patients.

METHODS

A total of 120 DAA-naïve HCV-HIV co-infected patients were included. HCV NS3/4Agenome region was amplified with PCR and mutation analysis was performed by Sanger sequencing technique. The amino acid sequence diversity of the region wasanalyzed using geno2pheno HCV.

RESULTS

Phylogenetic analysis showed that 73 cases were infected by 3a and 47 subjects by subtype1a. The overall RASs among studied subjects wereobserved in 6 (5%) individuals from 120 studied cases who were infected with HCV 1a. V36M/L,Q80L,S122G/L,R155T/G,A156S,D168Y/N and S174A/N/T mutations were detected in this study.

CONCLUSION

Although the prevalence of RASs was totally low in this study, the presence of several cases of double and triple mutants among this population suggests prior evaluation of protease inhibitors related mutations before initiation of standard treatment and also investigation on a large population could be of high value.

Global trend of aetiology-based primary liver cancer incidence from 1990 to 2030: a modelling study

BACKGROUND

Predictions of primary liver cancer (PLC) incidence rates and case numbers are critical to understand and plan for PLC disease burden.

METHODS

Data on PLC incidence rates and case numbers from 1990 to 2017 were retrieved from the Global Burden of Disease database. The estimated average percentage change (EAPC) was calculated to quantify the trends of PLC age-standardized incidence rates (ASRs). Bayesian age-period-cohort models were constructed to project PLC incidence rates and case numbers through 2030.

RESULTS

Globally, the PLC case number doubled from 472 300 in 1990 to 953 100 in 2017. The case number will further increase to 1 571 200 in 2030, and the ASR will increase from 11.80 per 100 000 in 2018 to 14.08 per 100 000 in 2030. The most pronounced increases are observed in people afflicted by non-alcoholic steatohepatitis (NASH) and in older people. The trends of PLC incidence rates between 1990 and 2030 are heterogeneous among countries and can be summarized as five scenarios: (i) 46 countries that have and will continue to experience a persistent increase (e.g. Australia); (ii) 21 countries that experienced an initial decrease (or remained stable) but are predicted to increase (e.g. China); (iii) 7 countries that experienced an initial increase but are predicted to remain stable (e.g. USA); (iv) 29 countries that experienced an initial increase but are predicted to decrease (e.g. Egypt); and (v) 82 countries that have and will continue to experience a persistent decrease (e.g. Japan).

CONCLUSION

PLC incidence rates and case numbers are anticipated to increase at the global level through 2030. The increases in people afflicted by NASH and among older people suggest a dearth of attention for these populations in current prevention strategies and highlight their priority in future schedules for global control of PLC.

Transmission of NS5A-Inhibitor Resistance-Associated Substitutions Among Men Who Have Sex With Men Recently Infected with Hepatitis C Virus Genotype 1a

The transmission of direct-acting antiviral resistance-associated substitutions (RAS) could hamper hepatitis C virus (HCV) cure rates and elimination efforts. A phylogenetic analysis of 87 men who have sex with men recently infected with HCV genotype 1a placed one-third (28/87) in a large cluster, in which 96% harbored NS5A M28V RAS.

Low level of baseline resistance in recently HCV-infected men who have sex with men with high-risk behaviours

OBJECTIVES

Presence of baseline hepatitis C virus (HCV) resistance-associated substitutions (RASs) can impair treatment outcome of direct-acting antivirals. We investigated the prevalence of pre-treatment HCV resistance among recently HCV-infected men who have sex with men (MSM) with high risk behaviours, either human immunodeficiency virus (HIV) co-infected or at high risk of HIV acquisition and under pre-exposure prophylaxis (PrEP).

METHODS

NS5A and NS3 fragments were deep sequenced on pre-treatment samples of 72 subjects using Illumina MiSeq paired-end sequencing technology. Ultra-deep sequencing data were analysed by SmartGene® platform. RASs mentioned in the literature were analysed and interpreted depending on genotype (GT) at 10% cut-off.

RESULTS

HCV genotyping showed 36 (50.0%) GT1a, 31 (43.1%) GT4d and 5 (6.9%) GT3a infections. Fifty-five patients (76.4%) were co-infected with HIV and 15 (20.8%) received PrEP. In GT1a viruses, NS3 RASs were found in 4/30 viruses (13.3%; S122 G/N, R155 K and I170 V) and Q80 K polymorphism was present in 14/30 viruses (46.7%). No NS3 RASs were detected in GT4d and GT3a viruses. NS5A RASs were detected in 3/36 GT1a viruses (8.3%; Q30E/R, L31 M and H58 L). NS5A subtype-specific polymorphisms L30R and T58 P were found at high frequencies in 31/31 (100%) and 16/31 (51.6%) GT4d viruses, respectively. One RAS M31 L was also observed along with the polymorphisms L30R and T58 P. No NS5A RASs were detected in GT3a viruses.

CONCLUSION

A low level of RASs to NS3 and NS5A inhibitors in pre-treatment samples was detected in the study population. Our findings reassure the clinical management of HCV infection in this high-risk population.

Molecular characterization of hepatitis C virus for subtype determination and resistance-associated substitutions detection among Chinese voluntary blood donors

BACKGROUND

The high prevalence of hepatitis C virus (HCV) infection and the resulting burden of the disease are significant issues to public health worldwide. Although direct-acting antiviral drugs (DAAs) with good tolerance and bioavailability are available, resistance-associated substitutions (RASs) often jeopardize the successful sustainment of virological responses in HCV treatment. High-frequency baseline RASs in treatment-naïve patients can lead to failures in DAA treatment. Clinical data on HCV RASs in patients from China are limited and require investigations.

METHODS

262 HCV RNA positive plasma from Chinese blood donors were genotyped and amplified with subtype-specific primers for NS3 and NS5A regions. RASs were analyzed using Geno2pheno. The codon usage of each resistance-associated substitution was calculated for genetic barrier analysis.

RESULTS

The two main subtypes in mainland China were 1b and 2a, followed by subtype 6a, 3b, 3a, and 1a. In NS3 region of 1b subtype, substitutions (T54S, V55A, Y56F, Q80 K/L, S122 G/T, R117 H/C, V170I and S174A) were present in 89.7% (96/107) of the samples. Other RASs (M28L, R30Q, P58 L/S and Y93H) were observed in 22.1% (25/113) of the samples in NS5A region. A crucial RAS, Q80K, and two other mutations (S122G + V170I) was identified in the same sequence, which reduced its susceptibility to protease inhibitor ASV and resulted in resistance to SMV. In NS5A, Y93H was detected in 9.7% (11/113) of the 1b samples, leading to medium-to-high level resistance to all six commercialized NS5A inhibitors. S122G-NS3 and Y93H-NS5A occurred simultaneously in 38.1% (7/22) of the samples with mutations in both two regions. Moreover, codon usage of S122G-NS3 and Y93H-NS5A revealed that both variants had the lowest genetic barrier and required only one transition to confer resistance.

CONCLUSIONS

Low genetic barriers facilitated the generation of resistance mutants and threated the efficacy of DAA regimens. The baseline RASs posed a great challenge to real-world DAA application.

HCV Antibody Prevalence and Genotype Evolution in a Teaching Hospital, Calabria Region, Southern Italy Over A Decade (2008-2018)

Background:

Hepatitis C Virus (HCV) infection is associated with a high risk of developing liver diseases. Globally, HCV prevalence is changing due to improving health care procedures, population movement, and availability of new antiviral therapy. In Italy, data on the prevalence of HCV infection are insufficient, out-dated, and restricted to specific areas.

Objective:

Between 2008 and 2018, we investigated HCV antibody (Ab) seroprevalence and genotypes distribution among patients presenting for testing at our Teaching Hospital.

Methods:

The HCV Ab and genotyping assays were performed by routine diagnostic methods. Chi-square for linear trend was carried out by OpenEpi (v3.01).

Results:

Among 120,009 consecutive patients, 5877 subjects were HCV Ab positive (4.89%). During the observational period 2008-2018, prevalence decreased significantly (p<0.001) from 4.7% in 2008 to 3.6% in 2018. HCV1b was the most prevalent subtype (47.2%) followed by HCV2a/2c (20.2%), and HCV3 (9.7%), while HCV4 showed a rate of 6.1%. HCV infection was more frequent in males (55.4%) than in females (44.6%). Overall, most infected patients were born before 1949.

Conclusion:

Epidemiological analyses are important to understand the evolution of the HCV epidemics under the influence of several factors, such as risk behaviour and therapy with direct-acting antivirals.