ITPA genotype protects against anemia during peginterferon and ribavirin therapy but does not influence virological response.

UNLABELLED: On-treatment anemia is associated with higher sustained virological response (SVR) rates during peginterferon plus ribavirin (RBV) therapy. Inosine triphosphatase (ITPA) variants causing ITPase deficiency have been shown to protect against RBV-induced anemia. However, ITPase activity has not been associated with SVR. To study this discrepancy, we examined the relationships between ITPase activity, on-treatment anemia, SVR, and RBV levels in hepatitis C virus genotype 1 (HCV-1) patients from the CHARIOT study. ITPA genotype (rs7270101, rs1127354) was used to define ITPase activity in 546 patients. Plasma RBV levels were measured using high-performance liquid chromatography (HPLC). Relationships between ITPase activity, on-treatment hemoglobin (Hb) levels, RBV levels, and SVR were tested using regression modeling, survival analysis, and locally weighted scatterplot smoothing (LOWESS) plot analysis. Hb decline was independently associated with SVR (P<0.0001). ITPase deficiency was present in 35%. ITPase deficiency strongly protected against Hb decline (P<0.0001), but was not associated with SVR (P=0.28). The probability of SVR increased with lower nadir Hb for both wild-type and deficient ITPase activity, but the association curve shifted to describe a parallel relationship at higher Hb levels in patients with ITPase deficiency. In a subset (n=203), we tested the hypothesis that the association between Hb decline and SVR reflected RBV levels rather than actual Hb level. RBV levels were associated with on-treatment Hb decline and SVR, but not ITPase activity. In regression models, adjustment for RBV levels attenuated the association between Hb decline and SVR. CONCLUSION: ITPase deficiency protects against RBV-induced anemia, but is not associated with SVR. Our data suggest that the relationship between Hb decline and SVR is not mechanistic, but is linked to RBV levels.

IL28B genotype is not useful for predicting treatment outcome in Asian chronic hepatitis B patients treated with pegylated interferon-α.

BACKGROUND AND AIM: IL28B genotype predicts response to pegylated interferon (peg-IFN)-based therapy in chronic hepatitis C. However, the utility of IL28B genotyping in chronic hepatitis B (CHB) cohorts treated with peg-IFN is unclear. It was investigated whether IL28B genotype is associated with peg-IFN treatment outcomes in a predominantly Asian CHB cohort. METHODS: This was a retrospective analysis of CHB patients treated with 48 weeks of peg-IFN monotherapy. IL28B genotype (rs12979860) was determined (TaqMan allelic discrimination kit). Baseline hepatitis B virus (HBV)-DNA, alanine aminotransferase, and liver histology were available. The primary end-points were HBV e antigen (HBeAg) seroconversion with HBV-DNA < 2000 IU/mL 24 weeks post-therapy (HBeAg-positive patients) and HBV-DNA < 2000 IU/mL 24 weeks after peg-IFN (HBeAg-negative patients). The association between IL28B genotype and peg-IFN outcomes was analyzed. RESULTS: IL28B genotype was determined for 96 patients. Eighty-eight percent were Asian, 62% were HBeAg positive, and 13% were METAVIR stage F3-4. Median follow-up time was 39.3 months. The majority of patients carried the CC IL28B genotype (84%). IL28B genotype did not differ according to HBeAg status. The primary end-points were achieved in 27% of HBeAg-positive and 61% of HBeAg-negative patients. There was no association between IL28B genotype and the primary end-point in either group. Furthermore, there was no difference in HBeAg loss alone, HBV surface antigen, alanine aminotransferase normalization, or on-treatment HBV-DNA levels according to IL28B genotype. CONCLUSIONS: In the context of a small possible effect size and high frequency in Asian populations, IL28B genotyping is likely to have, at best, limited clinical utility for predicting peg-IFN treatment outcome for CHB patients in the Asia-Pacific region.

Baseline serum HBV RNA is associated with the risk of hepatitis flare after stopping nucleoside analog therapy in HBeAg-negative participants.

BACKGROUND AND AIMS: HBV RNA in peripheral blood reflects HBV cccDNA transcriptional activity and may predict clinical outcomes. The prospective Melbourne HBV-STOP trial studied nucleot(s)ide analog discontinuation in HBeAg-negative non-cirrhotic participants with long-term virological suppression. Ninety-six weeks after stopping treatment, the proportion of participants with virological relapse (HBV DNA > 2000 IU/mL), biochemical relapse (ALT > 2 × ULN and HBV DNA > 2000 IU/mL), or hepatitis flare (ALT > 5 × ULN and HBV DNA > 2000 IU/mL) was 89%, 58%, and 38%, respectively. We evaluated the ability of serum HBV RNA levels to predict these outcomes. APPROACH RESULTS: HBV RNA levels were measured using the Roche cobas 6800/8800 HBV RNA Investigational Assay. Sixty-five participants had baseline and longitudinal off-treatment specimens available for RNA testing. HBV RNA was detectable at baseline in 25% of participants and was associated with a higher risk of biochemical relapse (81% vs. 51%, p value 0.04) and hepatitis flare (63% vs. 31%, p value 0.04). Participants who had undetectable serum HBV RNA as well as HBsAg ≤ 100 IU/mL at baseline were less likely to experience virological relapse (4 of 9, 44%) than participants with detectable HBV RNA and HBsAg level > 100 IU/mL (15/15, 100%; p value 0.0009). Off-treatment levels of HBV RNA were correlated with HBV DNA and were associated with the risk of hepatitis flare. CONCLUSIONS: Serum HBV RNA may be a useful biomarker for guiding clinical decision-making before stopping nucleot(s)ide analog therapy. Baseline HBV RNA and HBsAg levels are associated with the risk of clinical relapse, hepatitis flare, and disease remission off-treatment.

A multistate outbreak of hepatitis A associated with semidried tomatoes in Australia, 2009.

BACKGROUND: A large outbreak of hepatitis A affected individuals in several Australian states in 2009, resulting in a 2-fold increase in cases reported to state health departments compared with 2008. Two peaks of infection occurred (April-May and September-November), with surveillance data suggesting locally acquired infections from a widely distributed food product. METHODS: Two case-control studies were completed. Intensive product trace-back and food sampling was undertaken. Genotyping was conducted on virus isolates from patient serum and food samples. Control measures included prophylaxis for close contacts, public health warnings, an order by the chief health officer under the Victorian Food Act 1984, and trade-level recalls on implicated batches of semidried tomatoes. RESULTS: A multijurisdictional case-control study in April-May found an association between illness and consumption of semidried tomatoes (odds ratio [OR], 3.0; 95% CI 1.4-6.7). A second case-control study conducted in Victoria in October-November also implicated semidried tomatoes as being associated with illness (OR, 10.3; 95% CI, 4.7-22.7). Hepatitis A RNA was detected in 22 samples of semidried tomatoes. Hepatitis A virus genotype IB was identified in 144 of 153 (94%) patients tested from 2009, and partial sequence analysis showed complete identity with an isolate found in a sample of semidried tomatoes. CONCLUSIONS: The results of both case-control studies and food testing implicated the novel vehicle of semidried tomatoes as the cause of this hepatitis A outbreak. The outbreak was extensive and sustained despite public health interventions, the design and implementation of which were complicated by limitations in food testing capability and complex supply chains.

Stopping nucleot(s)ide analogues in non-cirrhotic HBeAg-negative chronic hepatitis B patients: HBsAg loss at 96 weeks is associated with low baseline HBsAg levels.

BACKGROUND AND AIMS: Current guidelines recommend long-term nucleot(s)ide analogue (NA) therapy for patients with HBeAg-negative chronic hepatitis B (CHB). However, disease remission has been described after stopping NA therapy, as well as HBsAg loss. METHODS: We performed a prospective multi-centre cohort study of stopping NA therapy. Inclusion criteria were HBeAg-negative CHB, the absence of cirrhosis and HBVDNA5× ULN occurred in 35 (32%); ALT flares were not associated with HBsAg loss. There were no unexpected safety issues. CONCLUSION: Virological reactivation was very common after stopping NA therapy and occurred earlier after stopping TDF versus ETV. The majority of patients had ALT <2× ULN at week 96, but only one-third achieved disease remission and HBsAg loss was rare. Very low HBsAg levels at baseline were uncommon but predicted for HBsAg loss and disease remission.

The Inaugural Australian Centre for Hepatitis Virology Public Panel Discussion on Viral Hepatitis Research-Lessons in Scientific Community Outreach.

Viral hepatitis remains one of the most significant health issues globally, directly responsible for over 1 million deaths each year and affecting almost 300 million people around the world. Scientific research in recent decades has brought about improvements in the lives of people living with chronic viral hepatitis. On the 29 July 2021, the Australian Centre for Hepatitis Virology (ACHV) for the first time held a public educational forum for the general public. The main aim of this event was to inform the affected community about the importance of scientific research and give an overview of upcoming developments in the field. Here, we provide a detailed report of the panel discussion (including its organisation, execution, and lessons learned to incorporate into future events) and provide strategies that can be used by other scientific societies to hold similar events in their own communities.

GB virus C genotype 2 predominance in a hepatitis C virus/HIV infected population associated with reduced liver disease.

BACKGROUND AND AIM: GB virus C (GBV-C) infection in hepatitis C virus (HCV)/HIV co-infection is associated with a significant reduction in the severity of HCV-related liver disease. The role of GBV-C genotype in this association is unknown. It has been suggested that GBV-C genotype may influence CD4 positive T-cell counts in HCV/HIV co-infected patients. The aim of the present study was to identify the GBV-C genotype in a HCV/HIV co-infected population and determine if the GBV-C genotype contributes to a reduction in HCV-related liver disease. METHODS: GBV-C RNA from 57 patients who were co-infected with HCV/HIV was analyzed. GBV-C RNA was detected by reverse transcription-polymerase chain reaction with primers to the NS5B gene and genotype determined by phylogenetic analysis after sequencing using E2 gene primers. RESULTS: Genotype 2 was the predominant isolate in our population and was detected in 50/56 (89.3%) of patients, although sequences with similarity to genotypes 1, 3, 4 and 5 were also identified. There was no statistical difference between CD4 positive T-cell counts in the GBV-C genotype 2 and non-genotype 2 groups. CONCLUSIONS: The GBV-C genotype distribution in our HCV/HIV patient group was consistent with that reported in other developed countries. The predominance of genotype 2 in this study meant that we could not draw a conclusion for the role of GBV-C genotype in the reduced severity of liver disease in co-infected patients but CD4 positive T-cell counts appeared to be unaffected by GBV-C genotype.

Reduction in hepatitis C-related liver disease associated with GB virus C in human immunodeficiency virus coinfection.

BACKGROUND & AIMS: It has been reported that GB virus C infection (GBV-C) leads to improved morbidity and mortality in patients with human immunodeficiency virus (HIV) infection. However, GBV-C has no effect on the course of liver disease in hepatitis C virus (HCV) monoinfection. The aim of the study was to determine the influence of GBV-C infection on liver disease in patients with HCV/HIV coinfection. METHODS: Data on 158 HCV/HIV patients were collected from January 1996 to October 2005. Two plasma specimens, collected at least 18 months apart, were tested for GBV-C RNA by reverse transcription-polymerase chain reaction with primers to the NS5B gene and confirmed using E2 gene primers and sequencing. Antibodies to GBV-C E2 protein were also determined. Liver-related morbidity and mortality were assessed from patient records. RESULTS: Fifty-seven of 158 (36%) patients had GBV-C RNA and 94 (59%) had evidence of exposure to GBV-C based on combined polymerase chain reaction and antibody results. Thirty-four (21%) patients had features of cirrhosis, with 20 having compensated and 14 having decompensated cirrhosis. Active GBV-C RNA was significantly associated with a reduction in cirrhosis, both compensated and decompensated in multivariate analysis (hazard ratio, 0.27; 95% confidence interval, 0.08-0.88; P = .03), as well as in analysis for cirrhosis-free survival vs duration of HCV infection (P = .006). No significant effect on liver-related or overall survival was observed. CONCLUSIONS: In these HCV/HIV-coinfected patients, GBV-C RNA was associated with a significant reduction in the severity of HCV-related liver disease.

GB virus C: insights into co-infection.

GB virus C (GBV-C) is a single stranded positive sense RNA virus, which is a member of the Flaviviridae. It has a close sequence homology and genomic organisation to hepatitis C virus (HCV). However, unlike HCV it is not hepatotrophic. GBV-C replicates within cells of the haemopoietic lineage, in particular lymphocytes. No disease has been associated with GBV-C infection but co-infection with human immunodeficiency virus (HIV) leads to improved morbidity and mortality for the HIV infected individual and slows progression to acquired immunodeficiency syndrome. This potential benefit of GBV-C has been demonstrated in the pre and post highly active anti-retroviral treatment (HAART) eras. GBV-C has been found to decrease HIV replication in in vitro models. The mechanism of the beneficial effect of GBV-C appears to be mediated by alterations in the cellular immune response, the details of which remain unclear. Despite this, there continues to be controversy regarding the influence of GBV-C on HIV as several reports have questioned the beneficial effect. GBV-C does not appear to influence liver related disease in subjects co-infected with HCV or hepatitis B virus (HBV). Combination of HIV and HCV leads to accelerated liver disease. The influence of GBV-C in this situation is yet to be determined. Elucidation of the putative protective effect of GBV-C in HIV co-infection could potentially identify novel targets for anti-HIV therapeutics and lead to the development of disease modifying vaccines.

Male to male sex is associated with a high prevalence of exposure to GB virus C.

Co-infection with GB virus C (GBV-C) and human immunodeficiency virus (HIV) appears to reduce mortality for HIV/AIDS. Epidemiological and demographic factors for GBV-C were examined prospectively in 167 subjects at risk for co-infection. We attempted to establish a hierarchical exposure risk for GBV-C. Overall exposure to GBV-C was 45.5%. In univariate analysis, GBV-C was associated with male to male sex (P<0.0001), HIV infection (P=0.0005) and hepatitis B infection (P=0.006). Injecting drug use approached statistical significance (P=0.08) while being a female sex worker was not associated with GBV-C exposure/infection (P=0.85). Exposure to GBV-C in 192 healthy blood donors was found to be 9.4%. In conclusion, the data suggest that male to male sex is a more effective mode of transmission of GBV-C and that GBV-C is associated with HIV co-infection. As male to male sex is also a risk factor for HIV transmission our data suggest that many may benefit from the potential protective effect GBV-C exerts on HIV-infected persons.

Analysis of Post-Liver Transplant Hepatitis C Virus Recurrence Using Serial Cluster of Differentiation Antibody Microarrays.

BACKGROUND: Hepatitis C virus (HCV) reinfection of the liver allograft after transplantation is universal, with some individuals suffering severe disease recurrence. Predictive markers of recurrent disease severity are urgently needed. In this study, we used a cluster of differentiation (CD) microarray to predict the severity of HCV recurrence after transplantation. METHODS: The CD antibody microarray assays of live leukocytes were performed on peripheral blood taken in the first year after transplantation. The results were grouped into phases defined as; Pre-transplant (day 0), Early (day 3 to week 2), Mid (week 4 to week 10), and Late (week 12 to week 26). Hepatitis C virus severity was based on fibrosis stages in the first 2 years (F0-1 mild and F2-4 severe). RESULTS: Serial blood samples from 16 patients were taken before and after liver transplantation. A total of 98 assays were performed. Follow-up was 3 years or longer. Comparing recurrence severity, significantly greater numbers of CD antigens were differentially expressed on the pretransplant samples compared to any posttransplant timepoints. Five differentially expressed CD antigens before transplantation (CD27 PH, CD182, CD260, CD41, and CD34) were significantly expressed comparing severe to mild recurrence, whereas expression of only CD152 was significant in the late phase after transplantation. No relationship was observed between the donor or recipient interleukin-28B genotypes and HCV recurrence severity. CONCLUSIONS: This study shows that circulating leukocyte CD antigen expression has utility in assessing recurrent HCV disease severity after liver transplantation and serves as a proof of principle. Importantly, pretransplant CD antigen expression is most predictive of disease outcome.

Validation of assembled nucleic acid-based tests in diagnostic microbiology laboratories.

Medical microbiology and virology laboratories use nucleic acid tests (NAT) to detect genomic material of infectious organisms in clinical samples. Laboratories choose to perform assembled (or in-house) NAT if commercial assays are not available or if assembled NAT are more economical or accurate. One reason commercial assays are more expensive is because extensive validation is necessary before the kit is marketed, as manufacturers must accept liability for the performance of their assays, assuming their instructions are followed. On the other hand, it is a particular laboratory's responsibility to validate an assembled NAT prior to using it for testing and reporting results on human samples. There are few published guidelines for the validation of assembled NAT. One procedure that laboratories can use to establish a validation process for an assay is detailed in this document. Before validating a method, laboratories must optimise it and then document the protocol. All instruments must be calibrated and maintained throughout the testing process. The validation process involves a series of steps including: (i) testing of dilution series of positive samples to determine the limits of detection of the assay and their linearity over concentrations to be measured in quantitative NAT; (ii) establishing the day-to-day variation of the assay's performance; (iii) evaluating the sensitivity and specificity of the assay as far as practicable, along with the extent of cross-reactivity with other genomic material; and (iv) assuring the quality of assembled assays using quality control procedures that monitor the performance of reagent batches before introducing new lots of reagent for testing.

New developments in HBV molecular diagnostics and quantitative serology.

New standardized assays for the quantification of hepatitis B virus (HBV) DNA have yielded insights into the association of HBV DNA levels with the relative risk of developing liver disease. Quantification of HBV DNA has also played a role in the management of chronic hepatitis B by allowing criteria to be established for determining patient eligibility for antiviral therapy, monitoring response, and identifying the development of resistance. In addition to serum HBV DNA levels, the HBV genotype may influence disease progression and response to therapy. However, many of the studies that have included genotype assessment do not compare across the range of genotypes, and current management guidelines do not incorporate genotype determination. More recently, quantitative assays for intrahepatic HBV replicative intermediates, as well as hepatitis B e antigen and hepatitis B surface antigen, indicate that these factors may have promise in identifying patients likely to respond to treatment. Additional work is needed to standardize and validate these assays before they can be considered to be of true diagnostic value. A wide variety of research techniques are being used to investigate chronic hepatitis B. Further evaluation is needed to decide which will have the greatest clinical applicability.

Lamivudine resistance in patients with chronic hepatitis B: role of clinical and virological factors.

BACKGROUND: Lamivudine resistance is associated with long-term monotherapy for chronic hepatitis B and can lead to potentially serious clinical consequences. Scant information exists regarding the influence of hepatitis B virus variants in the development of resistance. The present study was designed to identify factors predictive of lamivudine resistance, with a particular focus on the role of precore and basal core promoter variants in the setting of hepatitis B e antigen-negative disease. METHODS: Eighty-five patients, representing four major genotypes, were followed prospectively on lamivudine therapy. Resistance was defined as an increase in viral load, with polymerase gene sequencing confirming a lamivudine resistance mutation. Median follow up was 19 months (6-54 months). The Cox proportional hazards model was used to determine variables independently predicting for the early onset of lamivudine resistance. RESULTS: The rate of lamivudine resistance was 6%, 31% and 51% at 12, 24 and 48 months, respectively. Multivariate analysis identified the precore variant, high baseline alanine aminotransferase (ALT), and persistent viremia (at 6 months) as independent predictors of the early development of lamivudine resistance, with rate ratios of 4.93 (95% confidence interval [CI]: 1.32-18.5), 1.22 (95%CI: 1.08-1.49), and 4.73 (95%CI: 1.49-15.0), respectively (P < 0.05). Female sex predicted early resistance (rate ratio 5.27 [95%CI: 1.23-22.5, P < 0.05]) although numbers were small (n = 12). Genotype did not influence treatment response nor time to onset of resistance. CONCLUSION: Patients with precore variant hepatitis B virus are likely to develop lamivudine resistance early and should be considered for alternate first-line monotherapy. In the future, combination antiviral therapy may limit the development of resistance.

Chronic hepatitis C virus infection: genotyping and its clinical role.

Chronic hepatitis C virus (HCV) infection is a worldwide public health problem with a global prevalence of 2%. A high proportion of those infected are at risk of developing cirrhosis and hepatocellular carcinoma and modeling data predicts that the burden of disease could soon increase substantially. The liver disease associated with chronic infection has led investigators to look for correlates between viral properties and disease progression, severity of disease and the response to antiviral therapy. HCV has been classified into six genotypes but genotype does not appear to influence disease presentation or severity of disease. However, genotype has been identified as a major predictor of response to interferon-based antiviral therapy. Antiviral regimens have been optimized for infections with HCV genotypes 1-4, although treatment strategies for genotypes 5 and 6 have yet to be developed. The molecular basis for the differences in response of HCV genotypes has yet to be determined.

Effects of Silybum marianum on serum hepatitis C virus RNA, alanine aminotransferase levels and well-being in patients with chronic hepatitis C.

BACKGROUND/AIMS: Silybum marianum is a herbal preparation commonly used by subjects with chronic hepatitis C (CHC). The aims of this pilot study were to assess the efficacy and safety of S. marianum on serum hepatitis C virus (HCV) RNA, alanine aminotransferase levels and well-being in patients with CHC. METHODS: Twenty-four subjects with CHC were enrolled into a randomized, double-blind, placebo-controlled, crossover study. Subjects received 12 weeks of S. marianum (either 600 mg or 1200 mg/day) and placebo separated by a 4-week washout interval. Baseline biochemical, virological, psychological and quality-of-life tests were performed, with biochemical tests repeated monthly, and HCV RNA titer and quality-of-life and psychological assessments repeated at the end of both treatment periods. RESULTS: Seventeen patients completed the trial. Mean changes in HCV RNA titers, serum ALT levels and Short Form-36 scores were not significantly different for subjects on S. marianum compared to those on placebo. There was no significant change in mean State-Trait Anxiety Inventory State-Anxiety scores on S. marianum from baseline. Adverse events were similar with S. marianum and placebo. CONCLUSIONS: S. marianum is well tolerated in subjects with CHC, but does significantly affect serum HCV RNA, alanine aminotransferase levels, quality of life or psychological well-being in subjects with this condition.

Molecular epidemiology of hepatitis C virus in a social network of injection drug users.

BACKGROUND: We aimed to measure the overlap between the social networks of injection drug users (IDUs) and the patterns of related hepatitis C virus (HCV) infections among IDUs. METHODS: A cohort of 199 IDUs (138 of whom were HCV RNA positive) was recruited from a local drug scene in Melbourne, Australia, and was studied using social network analysis and molecular phylogenetic analysis of 2 regions of the HCV genome. RESULTS: Eighteen clusters of related infections involving 51 IDUs (37.0% of HCV RNA-positive IDUs) were detected; these clusters could be separated into 66 discrete pairs. Twelve (18.2%) of the 66 IDU pairs with related infections reported having previously injected drugs together; conversely, only 12 (3.8%) of the 313 pairs of HCV RNA-positive IDUs who were injection partners had strong molecular evidence of related infections. The social and genetic distances that separated IDUs with identical genotypes were weakly associated. Significant clusters of phylogenetically related sequences identified from core region analysis persisted in the analysis of the nonstructural 5a protein region. Genotyping and sequence analysis revealed 2 mixed-genotype infections. CONCLUSIONS: Static social network methods are likely to gather information about a minority of patterns of HCV transmission, because of the difficulty of determining historical infection pathways in an established social network of IDUs. Nevertheless, molecular epidemiological methods identified clusters of IDUs with related viruses and provided information about mixed-genotype infection status.