An Immunocompetent Mongolian Gerbil Model for Hepatitis E Virus Genotype 1 Infection.

BACKGROUND & AIMS: Hepatitis E virus (HEV), primarily genotype 1 (HEV-1), causes approximately 20.1 million infections, 44,000 deaths, and 3000 stillbirths annually. Current evidence indicates that HEV-1 is only transmitted in humans. Here, we evaluated whether Mongolian gerbils can serve as animal models for HEV-1 infection. METHODS: Mongolian gerbils were used for HEV-1 and hepatitis E virus genotype 3 infection experiments. HEV infection parameters, including detection of HEV RNA and HEV antigen, liver function assessment, and histopathology, were evaluated. RESULTS: We adapted a clinical isolate of HEV-1 for Mongolian gerbils by serial passaging in feces of aged male gerbils. The gerbil-adapted strain obtained at passage 3 induced a robust, acute HEV infection, characterized by stable fecal virus shedding, elevated liver enzymes, histopathologic changes in the liver, and seroconversion to anti-HEV. An infectious complementary DNA clone of the adapted virus was generated. HEV-1-infected pregnant gerbils showed a high rate of maternal mortality and vertical transmission. HEV RNA or antigens were detected in the liver, kidney, intestine, placenta, testis, and fetus liver. Liver and placental transcriptomic analyses indicated activation of host immunity. Tacrolimus prolonged HEV-1 infection, whereas ribavirin cleared infection. The protective efficacy of a licensed HEV vaccine was validated using this model. CONCLUSIONS: HEV-1 efficiently infected Mongolian gerbils. This HEV-1 infection model will be valuable for investigating hepatitis E immunopathogenesis and evaluating vaccines and antivirals against HEV.

Two mutations in the ORF1 of genotype 1 hepatitis E virus enhance virus replication and may associate with fulminant hepatic failure.

Hepatitis E virus (HEV) infection in pregnant women has a high incidence of developing fulminant hepatic failure (FHF) with significant mortality. Multiple amino acid changes in genotype 1 HEV (HEV-1) are reportedly linked to FHF clinical cases, but experimental confirmation of the roles of these changes in FHF is lacking. By utilizing the HEV-1 indicator replicon and infectious clone, we generated 11 HEV-1 single mutants, each with an individual mutation, and investigated the effect of these mutations on HEV replication and infection in human liver cells. We demonstrated that most of the mutations actually impaired HEV-1 replication efficiency compared with the wild type (WT), likely due to altered physicochemical properties and structural conformations. However, two mutations, A317T and V1120I, significantly increased HEV-1 replication. Notably, these two mutations simultaneously occurred in 100% of 21 HEV-1 variants from patients with FHF in Bangladesh. We further created an HEV-1 A317T/V1120I double mutant and found that it greatly enhanced HEV replication, which may explain the rapid viral replication and severe disease. Furthermore, we tested the effect of these FHF-associated mutations on genotype 3 HEV (HEV-3) replication and found that all the mutants had a reduced level of replication ability and infectivity, which is not unexpected due to distinct infection patterns between HEV-1 and HEV-3. Additionally, we demonstrated that these FHF-associated mutations do not appear to alter their sensitivity to ribavirin (RBV), suggesting that ribavirin remains a viable option for antiviral therapy for patients with FHF. The results have important implications for understanding the mechanism of HEV-1-associated FHF.

High real-world effectiveness of 12-week elbasvir/grazoprevir without resistance testing in the treatment of patients with HCV genotype 1a infection in Norway.

BACKGROUND AND AIMS: The recommended treatment duration of hepatitis C virus (HCV) genotype 1a (GT1a) infection with elbasvir/grazoprevir (EBR/GZR) in the presence of a high baseline viral load and resistance associated substitutions (RAS) is 16 weeks with ribavirin added. The objective of this study was to evaluate the real-world effectiveness of 12 weeks of EBR/GZR without ribavirin and regardless of baseline viral load and RAS testing. METHOD: This retrospective, observational cohort study was performed at five Norwegian hospitals that did not systematically utilize RAS testing. All adult patients with chronic HCV GT1a and compensated liver disease who had received 12 weeks of EBR/GZR without ribavirin and baseline RAS testing, were included. The primary endpoint was sustained virologic response at week 12 (SVR12), or if not available, at week 4 (SVR4). RESULTS: We included 433 patients and attained SVR data on 388. The mean age was 45.7 years (22-73 years). 67.2% were male. HIV co-infection was present in 3.8% (16/424) and cirrhosis in 4% (17/424). The viral load was >800 000 IU/mL in 55.0% (235/427) of patients. Overall SVR was achieved in 97.2% (377/388). SVR was achieved in 98.3% (169/172) of those with viral load ≤800 000 IU/mL and in 96.2% (202/210) of those with viral load >800 000 IU/mL. CONCLUSION: We observed high SVR rates among patients with HCV GT1a infection treated with EBR/GZR for 12 weeks without ribavirin, with no regard to baseline viral load and no RAS testing.

SID: a new carbohydrate blood group system based on a well-characterized but still mysterious antigen of great pathophysiologic interest.

The high-prevalence blood group antigen, Sda, had been puzzling blood bankers and transfusionists for at least a decade when it was reported in 1967. The characteristic mix of agglutinates and free red blood cells (RBCs), caused by anti-Sda, is seen with the RBCs from 90 percent of individuals of European descent. However, only 2-4 percent of individuals are truly Sd(a-) and may produce anti-Sda. The antibodies, generally considered insignificant, may cause hemolytic transfusion reactions with high-expressing Sd(a+) RBCs (e.g., the unusual Cad phenotype, which can also be polyagglutinable). The Sda glycan, GalNAcß1-4(NeuAcα2-3)Gal-R, is produced in the gastrointestinal and urinary systems, while its origin on RBCs is more controversial. According to current theory, Sda is likely to be passively adsorbed in low amounts, except in Cad individuals, where it has been found on erythroid proteins and at higher levels. The long-standing hypothesis that B4GALNT2 encodes the Sda synthase was confirmed in 2019, since homozygosity for a variant allele with rs7224888:C produces a non-functional enzyme associated with most cases of the Sd(a-) phenotype. Thereby, the SID blood group system was acknowledged as number 038 by the International Society of Blood Transfusion. Although the genetic background of Sd(a-) was settled, questions remain. The genetic background of the Cad phenotype has not yet been determined, and the source of the RBC-carried Sda is unknown. Furthermore, the interest of Sda stretches beyond transfusion medicine. Some tantalizing examples are lowered antigen levels in malignant tissue compared with normal tissue and interference with infectious agents like Escherichia coli, influenza virus, and malaria parasites.

Effect of baseline resistance-associated substitutions on the efficiency of glecaprevir/pibrentasvir in chronic hepatitis C subjects: A meta-analysis.

The effect of baseline resistance-associated substitutions on the sustained virologic response at 12 weeks in chronic hepatitis C subjects has drawn considerable attention. However, it has been reported that the relationship between such substitutions and sustained virologic response at 12 weeks in chronic hepatitis C subjects is variable in different treatments. This meta-analysis was performed to evaluate this relationship in subjects treated with glecaprevir/pibrentasvir. A systematic literature search up to May 2020 was done, and 17 studies were identified with 6501 chronic hepatitis C subjects. They were reporting relationships between baseline resistance-associated substitutions and sustained virologic response at 12 weeks in chronic hepatitis C subjects treated with glecaprevir/pibrentasvir. The odds ratio (OR) with 95% confidence intervals (CIs) was calculated to evaluate the prognostic role of baseline resistance-associated substitutions on the sustained virologic response at 12 weeks in chronic hepatitis C subjects treated with glecaprevir/pibrentasvir using the dichotomous method with a random or fixed-effect model. Lower sustained virologic response at 12 weeks post-treatment in chronic hepatitis C subjects was significantly related to baseline resistance-associated substitutions in overall genotypes (OR, 0.03; 95% CI, 0.15-0.61, P < .001), baseline NS5a resistance-associated substitutions in genotype-1 (OR, 0.16; 95% CI, 0.04-0.57, P = .005), baseline resistance-associated substitutions in genotype-3 (OR, 0.14; 95% CI, 0.05-0.38, P < .001), and baseline NS5a resistance-associated substitutions in genotype-3 (OR, 0.21; 95% CI, 0.09-0.49, P < .001). Sustained virologic response at 12 weeks in chronic hepatitis C subjects was not significantly related to the baseline NS5a resistance-associated substitutions (OR, 0.61; 95% CI, 0.17-2.22, P = .45), and baseline resistance-associated substitutions in genotype-1 (OR, 0.35; 95% CI, 0.12-1.088, P = .07). In conclusion, the impact of baseline resistance-associated substitutions on the sustained virologic response at 12 weeks in chronic hepatitis C subjects treated with glecaprevir/pibrentasvir may have a great prognostic effect, especially in genotype-3 as a tool to improve treatment prediction. Chronic hepatitis C subjects with baseline resistance-associated substitutions may have an independent risk relationship with poor treatment outcomes. This relationship forces us to recommend testing prior to treatment selection to avoid any possible treatment failure.

Hepatitis E virus genotype 1f outbreak in Bangladesh, 2018.

Hepatitis E virus (HEV) infection is a significant public health issue in many developing countries, causing waterborne outbreaks as well as sporadic hepatitis. We report here an outbreak of HEV genotype 1f infection during April-May 2018 among people living at Halisohor, a low land in the southern part of Chottogram District of Bangladesh. A total of 933 patients were admitted to Combined Military Hospital (CMH), Chottogram, with symptoms of acute hepatitis. Among them, 550 patients were tested by ELISA for HEV-specific (IgM) and all were positive. Genotyping, sequencing, and phylogenetic analysis based on ORF2 region revealed that the outbreak was caused by genotype 1f and the strains were closely related to the previously reported HEV strains that caused the outbreak in Bangladesh in 2010. The current outbreak was most likely linked with water supply as fecal contamination in water was evident and could be prevented by ensuring access to safe drinking water.

Development of a competitive ELISA for detecting antibodies against genotype 1 hepatitis E virus.

Hepatitis E, a significant global public health issue in China, is caused by sporadic infections with regional hepatitis E virus (HEV) genotypes 1, 3, and 4. To date, most immunoassays currently used to test human sera for the presence of anti-HEV antibodies cannot identify HEV at the genotype level. However, such information would be useful for identifying the source of infecting virus. Therefore, here we describe the development of a competitive enzyme-linked immunosorbent assay (ELISA) for detecting anti-genotype 1 HEV antibodies in human sera. Using recombinant genotype 1 HEV ORF3 protein as immunogen, traditional hybridoma technology was employed to generate seven monoclonal antibodies (mAbs), of which two mAbs specifically reacted with the immunogen. One of these two mAbs, 1D2, was labeled with horseradish peroxidase (HRP) for use in competitive ELISA (cELISA). After cELISA optimization using a checkerboard assay design, the amount of ORF3SAR-55 as coating antigen (100 ng/well), HRP-1D2 mAb concentration (1 µg/mL), and test serum dilution (1:10) were selected and a result ≥ 19.5 was used as the cutoff for a positive result. Importantly, cross-genotype cELISA results indicated that the cELISA could not detect anti-genotype 3 rabbit and 4 swine HEV antibodies. Moreover, human sera confirmed as negative for anti-HEV antibodies using the commercial ELISA kit were all negative via cELISA. However, because the commercial ELISA kit detects anti-all genotypes HEV antibodies and the cELISA only detects anti-genotype 1 HEV antibodies, the consistence rate of two assays detecting positive sera is low. In summary, here a cELISA for detecting anti-genotype 1 HEV antibodies was developed for use in epidemiological investigations of genotype 1 HEV infections in humans. KEY POINTS: • Seven mAbs were produced using genotype 1 HEV ORF3 protein as immunogen. • One mAb that specifically bound to genotype 1 HEV ORF3 protein was selected and labeled for use in a cELISA to detect anti-genotype 1 HEV antibodies. • The competitive ELISA developed here will aid clinical diagnosis of HEV infections and will be useful for large-scale serological testing of genotype 1 HEV infections in humans.

The efficacy and safety of elbasvir/grazoprevir treatment in HCV genotype 1 patients in Taiwan.

BACKGROUND: Elbasvir/grazoprevir (EBR/GZR) is a new generation, fixed-dose, combination antiviral drug used in chronic hepatitis C virus (HCV) genotype (GT) 1 or 4 infection. Our study evaluates the clinical efficacy and safety of EBR/GZR after its launch in Taiwan. METHODS: This is a retrospective observational study. Patients who had received EBR/GZR for chronic HCV GT 1 between June 2017 and April 2018 were recruited. Patients' age, sex, HCV GT, changes in HCV RNA level before and after treatment, sustained virologic response 12 weeks (SVR12) after the cessation of drug administration, side effects, and interaction effects were used to evaluate the clinical efficacy and safety. RESULTS: A total of 149 patients were recruited. Of them, 145 (97.3%) had HCV GT 1b, and the rest had HCV GT 1a; most of the EBR/GZR-related side effects in this study were mild. Three participants were discontinued because their alanine transaminase levels were elevated to over 10 times the upper limit of normal. The therapeutic effect analyses revealed a rapid virologic response rate of 95.3% and an SVR12 rate of 98%. Subgroup analyses performed using SVR12 as the outcome variable revealed three demographic factors HCV GT 1, hepatocellular carcinoma medical history, and noncirrhosis plus HCV RNA level. CONCLUSIONS: This study confirmed that EBR/GZR is safe and effective for treating patients with HCV GT 1 and exhibited excellent overall clinical efficacy in Taiwan. The therapeutic effects are unrelated to factors such as sex, HCV RNA level before treatment, and history of liver cirrhosis.

Treatment outcomes in hepatitis C virus genotype 1a infected patients with and without baseline NS5A resistance-associated substitutions.

BACKGROUND&AIMS: The presence of baseline resistance-associated substitutions (RASs) reduced sustained virologic response (SVR) rates in chronic hepatitis C virus (HCV) genotype 1a infected patients treated with Elbasvir/Grazoprevir (EBR/GZR). This study aimed to evaluate the frequency of NS5A RASs and treatment outcomes in patients for whom EBR/GZR was intended. METHODS: We sequenced NS5A in 832 samples from German genotype1a-infected DAA-naïve patients population-based, which were collected in the European Resistance Database. Treatment outcomes and clinical parameters were evaluated in 519 of these patients retrospectively. RESULTS: Overall, 6.5% of patients harbored EBR-specific NS5A RASs at baseline, including Q30H/R (3.3%), L31M (1.8%), Y93H (1.6%) and other individual variants. Antiviral treatment, including EBR/GZR, was initiated in 88% of patients. In the absence of RASs, the majority of patients received EBR/GZR for 12 weeks (57%) and the SVR rate was 97% compared to 99% SVR achieved using other DAA regimens (LDV/SOF±RBV, G/P, PrOD+RBV, VEL/SOF). Various regimens were used in the presence of RASs and SVR rates were high following treatment with LDV/SOF (100%), G/P (83%), PrOD/RBV (100%), VEL/SOF (100%), SMV/SOF (100%) and EBR/GZR+RBV for 16 weeks (100%). However, two patients received EBR/GZR for 16 weeks without RBV and one relapsed. CONCLUSIONS: EBR/GZR treatment with or without RBV for 12 or 16 weeks according to a baseline RAS analysis was highly effective with ≥97% SVR in patients with genotype 1a. EBR/GZR without RBV should be avoided in patients with RASs. High SVR rates were also achieved using other 8 or 12 weeks DAA regimens.

Analysis of IgG Anti-HEV Antibody Protective Levels During Hepatitis E Virus Reinfection in Experimentally Infected Rhesus Macaques.

BACKGROUND: Secondary spread of hepatitis E virus (HEV) infection occurs often in endemic settings in developing countries. The host immune signatures contributing to protection against subsequent HEV reinfection are unknown. METHODS: Twelve seroconverted rhesus macaques were reinoculated with homologous HEV genotype 1 (gt1, Sar-55) and followed for 115 days. HEV RNA, HEV-specific T-cell responses, IgG anti-HEV antibody, and the IgG anti-HEV avidity index were tested. RESULTS: Four animals with baseline IgG anti-HEV levels from 1.5 to 13.4 World Health Organization (WHO) U/mL evidenced reinfection as determined by HEV RNA in stool, and increase in IgG anti-HEV levels between 63- and 285-fold (P = .003). Eight animals with baseline IgG anti-HEV levels from 2.8 to 90.7 WHO U/mL did not develop infection or shed virus in feces, and IgG anti-HEV antibody levels were unchanged (P = .017). The 4 reinfected animals showed a lower HEV-IgG avidity index (average 35.5%) than the 8 protected animals (average 62.1%). HEV-specific interferon-gamma-producing T cells were 2-fold higher in reinfected animals (P = .018). CONCLUSIONS: Preexisting antibody and high IgG avidity index (>50%) are important factors for protection against HEV reinfection. HEV-specific T-cell responses were elevated in reinfected animals after subsequent exposure to HEV.

Efficacy and safety of ombitasvir/paritaprevir/ritonavir and dasabuvir with low-dose ribavirin in patients with chronic hepatitis C virus genotype 1a infection without cirrhosis.

Patients infected with hepatitis C virus (HCV) treated with interferon-free direct-acting antivirals may still require ribavirin. However, ribavirin is associated with adverse events that can limit its use. This open-label, multicentre, Phase 3 study evaluated the safety and efficacy of ombitasvir/paritaprevir/ritonavir + dasabuvir (OBV/PTV/r + DSV) with low-dose ribavirin for 12 weeks in genotype 1a-infected patients without cirrhosis. The primary efficacy endpoint was sustained virologic response at post-treatment Week 12 (SVR12). The primary safety endpoint was haemoglobin <10 g/dL during treatment and decreased from baseline. Overall, 105 patients enrolled. The SVR12 rate was 89.5% (n/N = 94/105; 95% CI, 83.7-95.4). The study did not achieve noninferiority versus the historic SVR12 rate for OBV/PTV/r + DSV plus weight-based ribavirin. Five patients experienced virologic failure, four discontinued, and two had missing SVR12 data. Excluding nonvirologic failures, the SVR12 rate was 94.9% (n/N = 94/99). One patient met the primary safety endpoint. OBV/PTV/r + DSV plus low-dose ribavirin offers an alternative option for patients in whom full-dose ribavirin may compromise tolerability, although noninferiority to the weight-based ribavirin regimen was not met.

Efficacy of direct-acting antivirals: UK real-world data from a well-characterised predominantly cirrhotic HCV cohort.

Direct-acting antivirals (DAAs) have revolutionised the management of chronic hepatitis C virus (HCV) infection. We describe UK real-world DAA experience. Individuals commencing HCV treatment containing a DAA regimen (Mar 2014-Nov 2016), participating in the National HCV Research UK (HCVRUK) Cohort Study were recruited from 33 UK HCV centers. The data were prospectively entered at sites onto a centralised database. The data were reported as median (Q1-Q3). Of the 1448 treated patients, 1054 (73%) were males, the median age being 54 years (47-60), 900 (62%) being genotype 1 and 455 (31%) genotype 3. The majority, 887 (61%) had cirrhosis, and 590 (41%) were treatment-experienced. DAA regimens utilised: genotype1 sofosbuvir (SOF)/Ledipasvir/±Ribavirin (625/900, 69%) and Ombitasvir/Paritaprevir/Dasabuvir/±RBV (220/900, 24%), and in genotype 3 SOF/Daclatasvir + RBV (256/455, 56%) and SOF/pegylated interferon/RBV (157/455, 35%). Overall, 1321 (91%) achieved sustained virological response (SVR12), genotype 1 vs 3, 93% vs 87%, P < .001. Prior treatment, presence of cirrhosis and treatment regimen did not impact SVR12. Predictors of treatment failure were genotype 3 infection, OR, 2.015 (95% CI: 1.279-3.176, P = .003), and male sex, OR, 1.878 (95% CI: 1.071-3.291, P = .028). Of those with hepatic decompensation at baseline (n = 39), 51% (n = 20) recompensated post-treatment, lower baseline serum creatinine being associated with recompensation (P = .029). There were two liver-related deaths, both having decompensated disease. This real-world UK data, comprising of a predominantly cirrhotic HCV genotype 1/3 cohort, confirms DAA efficacy with an overall 91% SVR12, with 51% recompensating post-treatment. Genotype 3 infection was a predictor of treatment failure.

First report of the genomic characterization of rubella viruses circulating in Cameroon.

Rubella is an acute and contagious viral infection whose gravidity resides in infection during pregnancy, which can result in miscarriage, fetal death, stillbirth, or infants with congenital malformations. This study aimed to describe the genome of rubella viruses (RUBVs) circulating in Cameroon. Throat swabs were collected from health districts as part of the measles surveillance program from 2010 to 2016 and sent to the Centre Pasteur of Cameroon. Samples were amplified by genotyping reverse transcription polymerase chain reaction (RT-PCR) in the search of two overlapping fragments of the gene that encodes the E1 envelope glycoprotein of RUBV. PCR products were sequenced and phylogenetic analysis was performed with MEGA 6 software. Overall, 9 of 43 samples (20.93%) were successfully amplified and sequenced but only eight sequences could be exploited for phylogenetic analysis with respect to the required fragment length of 739 nucleotides. Analysis of viral sequences from Cameroon with other epidemiologically relevant sequences from around the world showed that all RUBVs belonged to lineage L1 of genotype 1G. Cameroon sequences clustered with viruses from West Africa including Nigeria, Ivory Coast, and Ghana with a percentage similarity of 95.4% to 99.2%. This study will enable an update on the molecular epidemiology of RUBV in Cameroon and help in monitoring circulating RUBV for a better implementation of elimination strategies.

Clinical outcomes after the introduction of direct antiviral agents for patients infected with genotype 1b hepatitis C virus depending on the regimens: A multicenter study in Korea.

BACKGROUND: A real-life study is essential outside clinical trials. The aim is to evaluate the clinical outcomes of direct acting agents (DAA) for patients with chronic hepatitis C (CHC) in real practice. METHODS: We analyzed 590 consecutively enrolled patients with CHC-1b who received DAAs since 2015, when DAAs were introduced in Korea. The patients were checked for resistance-associated variants (RAV) against nonstructural protein 5A inhibitors and then daclatasvir/asunaprevir or sofosbuvir based regimens were chosen. RESULTS: The frequency of patients with cirrhosis and prior hepatocellular carcinoma (HCC) was 29.2% and 4.7%, respectively. For the RAV test, 10% were positive and in 3.6% the result was "indeterminate." Overall, 518 patients were treated with a 24-week regimen of daclatasvir/asunaprevir, 72 patients (RAV positive 75%) were treated with 12 weeks regimen of ledipasvir/sofosbuvir or daclatasvir/sofosbuvir. The SVR12 was 94.0% in the daclatasvir/asunaprevir, 98.2% in the ledipasvir/sofosbuvir, and 100% in the daclatasvir/sofosbuvir group. A total of 93.3% of SVR12 in the RAV-"indeterminate" patients was not difference 95.0% in the RAV-negative patients. Up to 1 year, de novo HCC occurrence and recurrence developed in 2.6% and 17.8%, respectively. HCC was more frequent in cirrhotic patients than in noncirrhotic patients (P = 0.000). α Fetoprotein (AFP) level at the end of treatment was a predicting factor for de novo HCC. CONCLUSIONS: Optimizing the choice of DAAs according to RAV test resulted in high SVR among CHC-1b Korean patients. This real practice multicenter cohort study suggests the importance of AFP and HCC surveillance in cirrhotic patients even after successful HCV therapy.

Frequency of baseline NS5A resistance-associated substitutions in patients infected with genotype 1 of hepatitis C virus in Croatia.

The backbone of current treatment for chronic Hepatitis C virus (HCV) infection are direct-acting antivirals targeting viral nonstructural proteins (NS3, NS4A, NS5A, NS5B). To date, there are six NS5A inhibitors approved for treatment of chronic HCV infection. The presence of drug-associated resistance substitutions is mainly due to fast error-prone replication, showing differential frequency between genotypes and subtypes. The aim of this study was to determine the frequency of baseline resistance to NS5A protein inhibitors in patients with genotype 1 HCV in Croatia. Resistance-associated substitutions (RAS) were detected by Sanger sequencing of HCV NS5A region amplified from 84 patients followed by phylogenetic analysis and analysis with Geno2Pheno algorithm. The frequency of NS5A RAS was 14.3% and highly dependent on viral subtype. The overall frequency of NS5A RAS was higher in patients infected with HCV subtype 1b (24.2%) than in those infected with HCV subtype 1a (7.8%). Overall, three resistance-conferring mutations were detected (Q30R, M28T and Y93H) along with two mutations (M28V and L31I) that cause reduced susceptibility to NS5A inhibitors. Analysis of the sequences showed two distinct subtype 1a clades with RAS detected in 4.3% (1/23) clade I and 10.7% (3/28) clade II sequences. Only a few distinct NS5A RAS were detected suggesting a high degree of homogeneity of the viral population. High frequency of clinically relevant NS5A RAS in Croatia suggest that the analysis of frequency and patterns of resistance mutations in local populations and evaluation of their possible clinical impact could be beneficial.

Characterization of a hepatitis C virus genotype 1 divergent isolate from an HIV-1 coinfected individual in Germany assigned to a new subtype 1o.

BACKGROUND: HCV exhibits a high genetic diversity and is classified into 7 genotypes which are further divided into 86 confirmed subtypes. However, there are multiple isolates with unassigned subtypes. We aimed to amplify and characterize the full-length genome sequence of an HCV genotype 1 (HCV-1) divergent isolate (DE/17-0414) in Germany. METHODS: The HCV infection was detected in an HIV-1-positive German female within an HCV/HIV-coinfection study using a commercially available antigen-antibody HCV ELISA kit and confirmed by an in-house quantitative real-time RT-PCR assay. Preliminary genotyping was done by sequencing and phylogenetic analysis on partial NS5B region. The full-length genome sequence was determined by consensus RT-PCR assays. Resistance-associated substitutions (RASs) were analyzed using the web-based tool Geno2pheno[HCV]. RESULTS: Partial NS5B region of the isolate DE/17-0414 showed more than 95% identity to 73-08460349-1 l and HCV_Fr_003 from France and QC316 from Canada. Full-length genome analysis of the DE/17-0414 strain showed 91.8% identity to QC316 but less than 79.6% to other HCV-1 strains. Phylogenetic analyses demonstrated that DE/17-0414, 73-08460349-1 l, HCV_Fr_003, and QC316 formed a separate subcluster within HCV-1. DE/17-0414 had a distinct 3 amino acids insertion at the N-terminal of hypervariable region 1 (HVR1) within viral envelope glycoprotein 2 (E2) and several potential antiviral RASs among the NS3 and NS5A genes. CONCLUSIONS: We identified and analyzed an HCV-1 divergent isolate derived from an HIV-1 coinfected individual in Germany, which will be assigned to a new HCV-subtype 1o. Our understanding of the origin and transmission dynamics of this new subtype 1o requires further assessments from patients worldwide.

Direct-acting antiviral agents for liver transplant recipients with recurrent genotype 1 hepatitis C virus infection: Systematic review and meta-analysis.

BACKGROUND: Comprehensive evaluation of safety and efficacy of different combinations of direct-acting antivirals (DAAs) in liver transplant recipients with genotype 1 (GT1) hepatitis C virus (HCV) recurrence remains limited. Therefore, we performed this systematic review and meta-analysis in order to evaluate the clinical outcome of DAA treatment in liver transplant patients with HCV GT1 recurrence. METHODS: Studies were included if they contained information of 12 weeks sustained virologic response (SVR12) after DAA treatment completion as well as treatment related complications for liver transplant recipients with GT1 HCV recurrence. RESULTS: We identified 16 studies comprising 885 patients. The overall pooled estimate proportion of SVR12 was 93% (95% confidence interval (CI): 0.89, 0.96), with moderate heterogeneity observed (τ2  = 0.01, P < 0.01, I2 =75%). High tolerability was observed in liver transplant recipients reflected by serious adverse events (sAEs) with pooled estimate proportion of 4% (95% CI: 0.01, 0.07; τ2  = 0.02, P < 0.01, I2  = 81%). For subgroup analysis, a total of five different DAA regimens were applied for treating these patients. Sofosbuvir/Ledipasvir (SOF/LDV) led the highest pooled estimate SVR12 proportion, followed by Paritaprevir/Ritonavir/Ombitasivir/Dasabuvir (PrOD), Daclatasvir (DCV)/Simeprevir (SMV) ± Ribavirin (RBV), and SOF/SMV ± RBV, Asunaprevir (ASV)/DCV. There was a tendency for favoring a higher pooled SVR12 proportion in patients with METAVIR Stage F0-F2 of 97% (95% CI: 0.93, 0.99) compared to 85% (95% CI: 0.79, 0.90) for stage F3-F4 (P < 0.01). There was no significant difference between LT recipients treated with or without RBV (P = 0.23). CONCLUSIONS: Direct-acting antiviral treatment is highly effective and well-tolerated in liver transplant recipients with recurrent GT1 HCV infection.

Efficacy of direct-acting antiviral treatment in patients with compensated liver cirrhosis: A multicenter study.

AIM: Although the development of new direct-acting antivirals (DAAs) for the treatment of chronic hepatitis C virus (HCV) infection has markedly advanced, the effects of cirrhosis on DAA treatment remain unclear. We aimed to clarify the impact of cirrhosis on DAA treatment of patients infected with HCV. METHODS: This large-scale, multicenter, retrospective study consisted of 2130 HCV genotype 1b-infected patients who were treated with one of the following DAA combination therapies: asunaprevir/daclatasvir (ASV/DCV), ledipasvir/sofosbuvir (LDV/SOF), or paritaprevir/ombitasvir/ritonavir (PTV/OBV/r). Ninety-two patients (4.3%) previously received DAA-based treatment. Seven hundred and forty-five patients (34.9%) had cirrhosis. RESULTS: Overall, the sustained virologic response (SVR) rate was 93.0%. The SVR rates in patients who received ASV/DCV, LDV/SOF, or PTV/OBV/r were 90.0%, 96.9%, and 97.6%, respectively. The SVR rate in patients with cirrhosis (89.1%) was significantly lower than that in patients without cirrhosis (95.1%, P = 6.94 × 10-7 ). In the multivariate analysis for the overall cohort, absence of cirrhosis (P = 1.26 × 10-3 ), no previous DAA-based treatment (P = 2.54 × 10-14 ), low HCV-RNA levels (P = 1.64 × 10-6 ), wild-type non-structural protein 5A L31/Y93 (P = 7.33 × 10-13 ), and DAA regimen (LDV/SOF or PTV/OBV/r) (P = 1.92 × 10-14 ) were independent factors contributing to SVR. Except for patients with DAA-based treatment history, absence of cirrhosis (P = 2.15 × 10-3 ; odds ratio, 2.51) was an independent factor contributing to SVR in 2038 DAA-naïve patients. CONCLUSION: This study suggests that the presence of cirrhosis reduces the SVR rate of DAA treatment, regardless of the type of DAA treatment.

Real-world efficacy of elbasvir and grazoprevir for hepatitis C virus (genotype 1): A nationwide, multicenter study by the Japanese Red Cross Hospital Liver Study Group.

AIM: The present study aimed to determine the real-world efficacy and safety of the non-structural protein (NS)5A inhibitor elbasvir (EBR) combined with the NS3/4A protease inhibitor grazoprevir (GZR) in patients with hepatitis C virus (HCV) genotype 1 (GT1) infection. METHODS: This study retrospectively evaluated the rate of sustained virologic response at 12 weeks post-treatment (SVR12) and the safety of EBR/GZR treatment in 159 men and 194 women with a median age of 72 years, and it assessed factors associated with the SVR12 rate. The attending physicians were responsible for selecting candidate patients for EBR/GZR in this retrospective study. RESULTS: Treatment outcomes for EBR/GZR were good in direct-acting antiviral (DAA)-naïve patients, of whom 99.4% achieved SVR. Of 353 patients, 10 (2.9%) had treatment failure. Of these patients, eight previously underwent DAA therapy, and the remaining two had NS5A-L31/Y93 double mutation. The SVR rate was 50% (8/16 patients) in patients who previously underwent DAA therapy, and 18.2% (2/11 patients) in patients with NS5A-L31/Y93 double mutation. On multivariate logistic regression analysis, NS5A-Y31/Y93 double mutation (odds ratio 356.3; 95% confidence interval, 23.91-16 940; P < 0.0001) was identified as an independent predictor of treatment failure. No serious adverse events were observed with EBR/GZR therapy. CONCLUSIONS: The SVR rate of EBR/GZR would have been 100% in patients without either a history of DAA therapy or double mutation. This combination of drugs could be safely given and is, thus, considered a highly useful first-line treatment for DAA-naïve patients with HCV.

Efficacy and safety of elbasvir plus grazoprevir combination therapy in Japanese patients infected with hepatitis C virus genotype 1b.

AIM: Treatment with all-oral direct-acting antiviral agents (DAAs) elbasvir/grazoprevir (EBR/GZR) is associated with high sustained virologic response (SVR). The aim of this study was to evaluate the safety and treatment efficacy of EBR/GZR in hepatitis C virus (HCV)-infected patients. METHODS: This retrospective cohort study included 147 consecutive patients with chronic HCV genotype 1b infection who were treated with EBR (50 mg) plus GZR (100 mg) once daily for 12 weeks. The rates of SVR at 12 weeks after the end of treatment (SVR12) were evaluated based on patient baseline characteristics. Treatment efficacy was analyzed according to background chronic kidney disease (CKD), and retreatment efficacy in patients who failed to respond to previous DAAs. RESULTS: The SVR12 was 94% (138 of 147 patients), based on intention-to-treat analysis. Rates of SVR12 were 97% (131 of 135) and 58% (7 of 12) in cases naïve to DAA treatment and failure to respond to prior DAAs, respectively. The SVR12 rates in patients with CKD stage 4-5 was 100% (8 of 8). All patients (4 of 4 patients) with stage 4-5 and advanced fibrosis (Fibrosis-4 index ≥3.25) also achieved SVR12. Multivariate analysis that included the above variables identified pretreatment with other DAAs as an independent factor that was significantly and independently associated with non-SVR12 (odds ratio, 97.5; P < 0.001). Relapsers of first DAAs, excluding the combination of ledipasvir and sofosbuvir, achieved SVR12. Characteristic novel non-structural protein 5A substitutions were not detected after failure of retreatment with EBR/GZR. CONCLUSION: Treatment with EBR/GZR was highly efficacious with acceptable safety, even in patients with CKD stage 4-5. Retreatment of relapsers to prior DAAs, excluding ledipasvir and sofosbuvir, achieved SVR12.