Viruses traverse the human proteome through peptide interfaces that can be biomimetically leveraged for drug discovery.

We present a drug design strategy based on structural knowledge of protein-protein interfaces selected through virus-host coevolution and translated into highly potential small molecules. This approach is grounded on Vinland, the most comprehensive atlas of virus-human protein-protein interactions with annotation of interacting domains. From this inspiration, we identified small viral protein domains responsible for interaction with human proteins. These peptides form a library of new chemical entities used to screen for replication modulators of several pathogens. As a proof of concept, a peptide from a KSHV protein, identified as an inhibitor of influenza virus replication, was translated into a small molecule series with low nanomolar antiviral activity. By targeting the NEET proteins, these molecules turn out to be of therapeutic interest in a nonalcoholic steatohepatitis mouse model with kidney lesions. This study provides a biomimetic framework to design original chemistries targeting cellular proteins, with indications going far beyond infectious diseases.

Circulating HBV RNA and hepatitis B core-related antigen trajectories in persons with HIV/HBV coinfection and HBsAg loss on tenofovir therapy.

BACKGROUND: We evaluated long-term trajectories of circulating hepatitis B virus (HBV)-RNA and hepatitis B core-related antigen (HBcrAg) in persons with and without hepatitis B surface antigen (HBsAg) loss during tenofovir therapy in the Swiss HIV Cohort Study. METHODS: We included 29 persons with HIV (PWH) with HBsAg loss and 29 matched PWH without loss. We compared HBV-RNA and HBcrAg decline and assessed the cumulative proportions with undetectable HBV-RNA and HBcrAg levels during tenofovir therapy using Kaplan-Meier estimates. RESULTS: HBsAg loss occurred after a median of 4 years (IQR 1 - 8). All participants with HBsAg loss achieved suppressed HBV-DNA and undetectable HBV-RNA preceding undetectable qHBsAg levels, whereas 79% achieved negative HBcrAg. In comparison, 79% of the participants without HBsAg loss achieved undetectable HBV-RNA and 48% negative HBcrAg. After two years on tenofovir, an HBV RNA decline ≥1 log10 copies/ml had 100% sensitivity and 36.4% specificity for HBsAg loss, whereas an HBcrAg decline ≥1 log10 U/ml had 91.0% sensitivity and 64.5% specificity. CONCLUSIONS: HBV-RNA suppression preceded undetectable qHBsAg levels, and had high sensitivity but low specificity for HBsAg loss during tenofovir therapy in PWH. HBcrAg remained detectable in approximately 20% of persons with, and 50% of persons without HBsAg loss.

Quantification of circulating HBV RNA expressed from intrahepatic cccDNA in untreated and NUC treated patients with chronic hepatitis B.

OBJECTIVE: A convenient, reproducible biomarker of hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) transcriptional activity is lacking. We measured circulating HBV RNA (cirB-RNA) in untreated and nucleos(t)ide analogues (NUC) treated chronic hepatitis B (CHB) patients to define its correlation with intrahepatic viral markers and HBV core-related antigen (HBcrAg). DESIGN: Paired liver biopsy and serum samples were collected from 122 untreated and 30 NUC-treated CHB patients. We measured cirB-RNA, HBV DNA, hepatitis B surface antigen (HBsAg), HBcrAg and alanine aminotransferase levels. cirB-RNA was quantified using an investigational HBV RNA assay for use on the cobas 6800 system. The test detects a region spanning the HBV canonical polyadenylation site. cccDNA and 3.5 kb RNA in liver tissue were assessed by quantitative PCR and droplet digital PCR. RESULTS: cirB-RNA was detectable in 100% of HBeAg(+) chronic hepatitis (CH), 57% and 14% of HBeAg(-) CH and chronic infection untreated patients and 47% of NUC-treated patients. cirB-RNA undetectability was associated with lower intrahepatic cccDNA transcriptional activity, as well as serum HBcrAg, but no significant differences in HBsAg, in both untreated and treated patients. In untreated HBeAg(-) patients, cirB-RNA correlated with intrahepatic 3.5 kb RNA and cccDNA transcriptional activity, serum HBV DNA and HBcrAg, but not with HBsAg or total cccDNA levels. Combined undetectability of both cirB-RNA and HBcrAg detection in untreated HBeAg(-) patients identified a subgroup with the lowest levels of intrahepatic transcriptionally active cccDNA. CONCLUSION: Our results support the usefulness of quantification of circulating HBV RNA expressed from cccDNA as an indicator of intrahepatic active viral reservoir in both untreated and NUC-treated CHB patients. TRIAL REGISTRATION NUMBER: NCT02602847.

Helicases DDX5 and DDX17 promote heterogeneity in HBV transcription termination in infected human hepatocytes.

BACKGROUND & AIMS: Transcription termination fine-tunes gene expression and contributes to the specification of RNA function in eukaryotic cells. Transcription termination of HBV is subject to the recognition of the canonical polyadenylation signal (cPAS) common to all viral transcripts. However, the regulation of this cPAS and its impact on viral gene expression and replication is currently unknown. METHODS: To unravel the regulation of HBV transcript termination, we implemented a 3' RACE (rapid amplification of cDNA ends)-PCR assay coupled to single molecule sequencing both in in vitro-infected hepatocytes and in chronically infected patients. RESULTS: The detection of a previously unidentified transcriptional readthrough indicated that the cPAS was not systematically recognized during HBV replication in vitro and in vivo. Gene expression downregulation experiments demonstrated a role for the RNA helicases DDX5 and DDX17 in promoting viral transcriptional readthrough, which was, in turn, associated with HBV RNA destabilization and decreased HBx protein expression. RNA and chromatin immunoprecipitation, together with mutation of the cPAS sequence, suggested a direct role of DDX5 and DDX17 in functionally linking cPAS recognition to transcriptional readthrough, HBV RNA stability and replication. CONCLUSIONS: Our findings identify DDX5 and DDX17 as crucial determinants of HBV transcriptional fidelity and as host restriction factors for HBV replication. IMPACT AND IMPLICATIONS: HBV covalently closed circular (ccc)DNA degradation or functional inactivation remains the holy grail for the achievement of HBV cure. Transcriptional fidelity is a cornerstone in the regulation of gene expression. Here, we demonstrate that two helicases, DDX5 and DDX17, inhibit recognition of the HBV polyadenylation signal and thereby transcriptional termination, thus decreasing HBV RNA stability and acting as restriction factors for efficient cccDNA transcription and viral replication. The observation that DDX5 and DDX17 are downregulated in patients chronically infected with HBV suggests a role for these helicases in HBV persistence in vivo. These results open new perspectives for researchers aiming at identifying new targets to neutralise cccDNA transcription.

A 3-Year Course Of Bulevirtide Monotherapy May Cure Hdv Infection In Cirrhotics.

Bulevirtide has been recently conditionally approved by the European Medicines Agency for the treatment of Chronic Hepatitis Delta, but the ideal duration of therapy is unknown. Here we describe the first case of cure of Hepatitis Delta following 3 years of Bulevirtide monotherapy in a patient with compensated cirrhosis and esophageal varices. During the 72-week off-Bulevirtide follow-up, virological and biochemical responses were maintained. In the off-therapy liver biopsy, intrahepatic HDV RNA and Hepatitis D antigen were undetectable, <1% hepatocytes were Hepatitis B surface antigen positive while hepatitis B core antigen was negative. Grading and staging improved compared to pre-treatment biopsy.

Profile of patients with a positive HCV viral load in a large French psychiatric hospital (2019-2021): A case-control study.

Hepatitis C virus (HCV) is highly prevalent in people with mental disorders (PWMDs). However, in the international context of HCV elimination, no previous study has explored the features of seropositive PWMDs with vs. without a positive viral load (VL). We retrospectively retrieved all HCV serology results of patients hospitalized in 2019, 2020 and 2021 in the second-largest psychiatric hospital of France. Using the medical records of all patients found seropositive for HCV, the following data were collected: sex (male, female), age (in years), previous history of illicit drug use except cannabis (yes or no) and previous history of incarceration (yes or no). We conducted a case-control comparison of these variables between the PWMDs who had and did not have a positive VL, thus providing odds ratios and 95% confidence intervals (ORs [95% CI]). In a total of 13,276 inpatients, 2540 (19.1%) underwent at least one HCV serology; 55 of them (2.16%) were found positive. A VL count was performed for 48 of them, finding 15 (31.3%) individuals with active HCV. Compared with those with a negative VL, these 15 individuals were less likely to have previous documented illicit drug use (OR = 0.18; 95% CI [0.05-0.68]) and to have been previously incarcerated (OR = 0.23; 95% CI [0.06-0.99]); age and sex did not statistically differ. In the context of HCV elimination, PWMDs yet to be treated for HCV are more likely to be those with no identified risk factor for HCV, which supports a strategy of systematic screening for HCV among PWMDs.

Improved hepatitis delta virus genome characterization by single molecule full-length genome sequencing combined with VIRiONT pipeline.

Hepatitis B virus (HBV) and hepatitis D virus (HDV) coinfection confers a greater risk for accelerated liver disease progression. Full-length characterization of HDV genome is necessary to understand pathogenesis and treatment response. However, owing to its high variability and tight structure, sequencing approaches remain challenging. Herein, we present a workflow to amplify, sequence, and analyze the whole HDV genome in a single fragment. Sequencing was based on the Oxford Nanopore Technologies long-read sequencing followed by a turnkey analysis pipeline (VIRiONT, VIRal in-house ONT sequencing analysis pipeline) that we developed and make available online for free. For the first time, HDV genome was successfully amplified and full-length sequenced in a single fragment, allowing accurate subtyping from 30 clinical samples. High variability of edition, a crucial step in viral life cycle, was found among samples (from 0% to 59%). Additionally, a new subtype of HDV genotype 1 was identified. We provide a complete workflow for assessment of HDV genome at full-length quasispecies resolution overcoming genome assembly issues and helping to identify modifications throughout the whole genome. This will help a better understanding of the impact of genotype/subtype, viral dynamics, and structural variants on HDV pathogenesis and treatment response.

Bulevirtide monotherapy for 48 weeks in patients with HDV-related compensated cirrhosis and clinically significant portal hypertension.

BACKGROUND & AIMS: Bulevirtide (BLV) has recently been conditionally approved for the treatment of chronic hepatitis delta (CHD) in Europe, but its effectiveness and safety in patients with compensated cirrhosis and clinically significant portal hypertension (CSPH) are unknown. METHODS: Consecutive patients with HDV-related compensated cirrhosis and CSPH who started BLV 2 mg/day were enrolled in this single-center study. Clinical/virological characteristics were collected at baseline, weeks 4, 8 and every 8 weeks thereafter. HDV RNA was quantified by Robogene 2.0 (lower limit of detection 6 IU/ml). RESULTS: Eighteen Caucasian patients with compensated cirrhosis and CSPH under nucleos(t)ide analogue treatment were enrolled: median (IQR) age was 48 (29-77) years, and 67% were male. Median (IQR) platelet count was 70 (37-227) x103/µl, liver stiffness measurement (LSM) 16.4 (7.8-57.8) kPa, alanine aminotransferase (ALT) 106 (32-222) U/L, HBsAg 3.7 (2.5-4.3) log IU/ml, HDV RNA 4.9 (3.3-6.6) log IU/ml. During 48 weeks of BLV monotherapy, HDV RNA declined by 3.1 (0.2-4.3) log IU/ml (p <0.001 vs. baseline), becoming undetectable in 5 patients (23%). A virological response was observed in 14 (78%) patients while a non-response was observed in 2 (11%). ALT decreased to 35 (15-86) U/L (p <0.001 vs. baseline), normalizing in 83% of patients. A combined response was observed in 67% of patients. Aspartate aminotransferase and gamma-glutamyltransferase levels significantly improved. Concerning liver function parameters, albumin values significantly increased and bilirubin remained stable. LSM significantly improved in patients with virological response, while platelet count was unchanged. None of the patients developed decompensating events or hepatocellular carcinoma. BLV was well tolerated, no patient discontinued treatment and the increase in bile acids was fully asymptomatic. CONCLUSIONS: A 48-week course of BLV 2 mg/day monotherapy is safe and effective even for difficult-to treat patients with HDV-related compensated cirrhosis and CSPH. LAY SUMMARY: Hepatitis delta virus (HDV) is associated with the most severe form of viral hepatitis. A new treatment for HDV called bulevirtide has recently received conditional approval for patients with chronic HDV infection. However, its safety and effectiveness in patients with more advanced liver disease is not known. Herein, we show that it is safe and effective in patients with HDV-related cirrhosis and clinically significant portal hypertension.

Safety and effectiveness of up to 3 years' bulevirtide monotherapy in patients with HDV-related cirrhosis.

The entry inhibitor bulevirtide (BLV) received conditional approval from the EMA in July 2020 for the treatment of adult patients with compensated chronic hepatitis delta. However, the effectiveness and safety of BLV administered as monotherapy beyond 48 weeks in difficult-to-treat patients with HDV-related cirrhosis is presently unknown. Herein, we describe the first patients with HDV-related compensated cirrhosis who were treated with BLV (10 mg/day as a starting dose) for up to 3 years on a compassionate use program. Patients were also monitored for HBcrAg and HBV RNA levels, and HDV- and HBV-specific T-cell markers. In the patient who stopped BLV at week 48, after achieving a virological and biochemical response, the initial virological and biochemical rebound was followed by alanine aminotransferase normalization coupled with low HDV RNA and HBsAg levels. In the 2 patients treated continuously for 3 years, virological and biochemical responses were maintained throughout the treatment period even after dose reduction. In a patient with advanced compensated cirrhosis, liver function tests significantly improved, esophageal varices disappeared, and histological/laboratory features of autoimmune hepatitis resolved. Overall, no safety issues were recorded, as bile salt increase was asymptomatic. While serum HBV RNA levels remained undetectable in all patients, HBV core-related antigen levels showed a progressive, yet modest decline during long-term BLV treatment. No HDV-specific interferon-γ-producing T cells were detected, neither after HDV reactivation (after BLV withdrawn in Patient 1) nor during 3 years of BLV treatment. In conclusion, this report shows that continuous administration of BLV monotherapy for 3 years leads to excellent virological and clinical responses in patients with HDV-related cirrhosis who had contraindications to interferon-based therapies.

Factors associated with the emergence of integrase resistance mutations in patients failing dual or triple integrase inhibitor-based regimens in a French national survey.

BACKGROUND: Successful 2-drug regimens (2DRs) for HIV were made possible by the availability of drugs combining potency and tolerability with a high genetic barrier to resistance. How these deal with resistance development/re-emergence, compared with 3DRs, is thus of paramount importance. MATERIALS AND METHODS: A national survey including patients who were either naive or experienced with any 2DR or 3DR but failing integrase strand transfer inhibitor (INSTI)-containing regimens [two consecutive plasma viral load (VL) values >50 copies/mL] was conducted between 2014 and 2019. Genotypic resistance tests were interpreted with the v28 ANRS algorithm. RESULTS: Overall, 1104 patients failing any INSTI-containing regimen (2DRs, n = 207; 3DRs, n = 897) were analysed. Five hundred and seventy-seven (52.3%) patients were infected with a B subtype and 527 (47.3%) with non-B subtypes. Overall, 644 (58%) patients showed no known integrase resistance mutations at failure. In multivariate analysis, factors associated with the emergence of at least one integrase mutation were: high VL at failure (OR = 1.24 per 1 log10 copies/mL increase); non-B versus B subtype (OR = 1.75); low genotypic sensitivity score (GSS) (OR = 0.10 for GSS = 2 versus GSS = 0-0.5); and dolutegravir versus raltegravir (OR = 0.46). Although 3DRs versus 2DRs reached statistical significance in univariate analysis (OR = 0.59, P = 0.007), the variable is not retained in the final model. CONCLUSIONS: This study is one of the largest studies characterizing integrase resistance in patients failing any INSTI-containing 2DR or 3DR in routine clinical care and reveals factors associated with emergence of integrase resistance that should be taken into consideration in clinical management. No difference was evidenced between patients receiving a 2DR or a 3DR.

Origin, HDV genotype and persistent viremia determine outcome and treatment response in patients with chronic hepatitis delta.

BACKGROUND & AIMS: HDV infection causes severe chronic liver disease in individuals infected with HBV. However, the factors associated with poor prognosis are largely unknown. Thus, we aimed to identify prognostic factors in patients with HDV infection. METHODS: The French National Reference Centre for HDV performed a nationwide retrospective study on 1,112 HDV-infected patients, collecting epidemiological, clinical, virological and histological data from the initial referral to the last recorded follow-up. RESULTS: The median age of our cohort was 36.5 (29.9-43.2) years and 68.6% of our cohort were male. Most patients whose birthplace was known were immigrants from sub-Saharan Africa (52.5%), southern and eastern Europe (21.3%), northern Africa and the Middle East (6.2%), Asia (5.9%) and South America (0.3%). Only 150 patients (13.8%) were French native. HDV load was positive in 659 of 748 tested patients (88.1%). HDV-1 was predominant (75.9%), followed by sub-Saharan genotypes: HDV-5 (17.6%), HDV-7 (2.9%), HDV-6 (1.8%) and HDV-8 (1.6%). At referral, 312 patients (28.2%) had cirrhosis, half having experienced at least 1 episode of hepatic decompensation. Cirrhosis was significantly less frequent in African than in European patients regardless of HDV genotype. At the end of follow-up (median 3.0 [0.8-7.2] years), 48.8% of the patients had developed cirrhosis, 24.2% had ≥1 episode(s) of decompensation and 9.2% had hepatocellular carcinoma. European HDV-1 and African HDV-5 patients were more at risk of developing cirrhosis. Persistent replicative HDV infection was associated with decompensation, hepatocellular carcinoma and death. African patients displayed better response to interferon therapy than non-African patients (46.4% vs. 29.1%, p <0.001). HDV viral load at baseline was significantly lower in responders than in non-responders. CONCLUSION: Place of birth, HDV genotype and persistent viremia constitute the main determinants of liver involvement and response to treatment in chronic HDV-infected patients. LAY SUMMARY: Chronic liver infection by hepatitis delta virus (HDV) is the most severe form of chronic viral hepatitis. Despite the fact that at least 15-20 million people are chronically infected by HDV worldwide, factors determining the severity of liver involvement are largely unknown. By investigating a large cohort of 1,112 HDV-infected patients followed-up in France, but coming from different areas of the world, we were able to determine that HDV genotype, place of birth (reflecting both viral and host-related factors) and persistent viremia constitute the main determinants of liver involvement and response to treatment.

Serum hepatitis B core-related antigen (HBcrAg) correlates with covalently closed circular DNA transcriptional activity in chronic hepatitis B patients.

BACKGROUND & AIMS: It has been proposed that serum hepatitis B core-related antigen (HBcrAg) reflects intrahepatic covalently closed circular (ccc)DNA levels. However, the correlation of HBcrAg with serum and intrahepatic viral markers and liver histology has not been comprehensively investigated in a large sample. We aimed to determine if HBcrAg could be a useful therapeutic marker in patients with chronic hepatitis B. METHODS: HBcrAg was measured by chemiluminescent enzyme immunoassay in 130 (36 hepatitis B e antigen [HBeAg]+ and 94 HBeAg-) biopsy proven, untreated, patients with chronic hepatitis B. HBcrAg levels were correlated with: a) serum hepatitis B virus (HBV)-DNA, quantitative hepatitis B surface antigen and alanine aminotransferase levels; b) intrahepatic total (t)HBV-DNA, cccDNA, pregenomic (pg)RNA and cccDNA transcriptional activity (defined as pgRNA/cccDNA ratio); c) fibrosis and necroinflammatory activity scores. RESULTS: HBcrAg levels were significantly higher in HBeAg+ vs. HBeAg- patients and correlated with serum HBV-DNA, intrahepatic tHBV-DNA, pgRNA and cccDNA levels, and transcriptional activity. Patients who were negative for HBcrAg (<3 LogU/ml) had less liver cccDNA and lower cccDNA activity than the HBcrAg+ group. Principal component analysis coupled with unsupervised clustering identified that in a subgroup of HBeAg- patients, higher HBcrAg levels were associated with higher serum HBV-DNA, intrahepatic tHBV-DNA, pgRNA, cccDNA transcriptional activity and with higher fibrosis and necroinflammatory activity scores. CONCLUSIONS: Our results indicate that HBcrAg is a surrogate marker of both intrahepatic cccDNA and its transcriptional activity. HBcrAg could be useful in the evaluation of new antiviral therapies aiming at a functional cure of HBV infection either by directly or indirectly targeting the intrahepatic cccDNA pool. LAY SUMMARY: Hepatitis B virus causes a chronic infection which develops into severe liver disease and liver cancer. The viral covalently closed circular DNA (cccDNA) is responsible for the persistence of the infection in hepatocytes. To better manage patient treatment and follow-up, and to develop new antiviral treatments directly targeting the intrahepatic pool of cccDNA, serum surrogate markers reflecting the viral activity in the liver are urgently needed. In this work, we demonstrate that quantification of hepatitis B core-related antigen in serum correlates with cccDNA amount and activity and could be used to monitor disease progression.

Chronic Genotype 3 Hepatitis E in Pregnant Woman Receiving Infliximab and Azathioprine.

Acute hepatitis E virus infection during pregnancy has a high fatality rate in developing countries. Little data are available on chronic infection in pregnant women. We report a case of chronic hepatitis E during treatment with infliximab and azathioprine, without adverse event during pregnancy and with spontaneous resolution after delivery.

Very late relapse of hepatitis C virus infection immediately after liver transplant.

Late relapse of hepatitis C virus (HCV) infection is very rare in the era of modern direct-acting antiviral therapy. We report here the first case of a late relapse, after direct-acting antiviral therapy, occurring immediately after liver transplant (LT), with 93 weeks of sustained virologic response before LT. HCV RNA in serum and in liver biopsy was negative the day of LT, and relapse was diagnosed 11 days after LT. HCV NS5A sequencing was performed on samples before and after LT, with 99% of homology demonstrating a true late relapse rather than a reinfection. This late relapse could be explained by extrahepatic reservoirs of HCV and the high immunosuppressive therapy, including bolus of steroids, within the first days post LT. In conclusion, our case suggests that monitoring HCV RNA after LT could be recommended to detect and treat early relapse, even after a long virologic response.

Interaction between Toll-Like Receptor 9-CpG Oligodeoxynucleotides and Hepatitis B Virus Virions Leads to Entry Inhibition in Hepatocytes and Reduction of Alpha Interferon Production by Plasmacytoid Dendritic Cells.

We previously reported that Toll-like receptor 9 (TLR9)-CpG oligonucleotides could inhibit the establishment of hepatitis B virus (HBV) infections in hepatocytes. Our aim was to uncover the underlying mechanisms of this inhibition. HepaRG cells, RPMI-B lymphoblastoma cells, and primary plasmacytoid dendritic cells (pDCs) exposed to HBV and TLR9 ligands/agonists in various configurations were used. We observed an inhibition of HBV infection upon TLR9 stimulations only when agonist was applied during inoculation. This inhibition was independent of interleukin-6 (IL-6)/interferon-inducible protein 10 (IP-10) production as well as of TLR9 expression in hepatocytes. We further demonstrated an entry inhibition mechanism by showing a noncovalent binding of TLR9 agonist to HBV particles. Besides inhibiting HBV entry into hepatocytes, this biophysical interaction between HBV virions and TLR9 agonist was responsible for a reduction of alpha interferon (IFN-α) expression by pDCs. Interestingly, subviral particles composed of only HBsAg were able to genuinely inhibit the TLR9 pathway, without titrating TLR9 ligands. To conclude, our data suggest that synthetic TLR9-CpG oligonucleotides can strongly inhibit HBV entry by "coating" HBV virions and thereby preventing their interaction with cellular receptor. This titration effect of TLR9 agonist is also artifactually responsible for the inhibition of TLR9 engagement in pDCs, whereas a genuine inhibition of this innate pathway was confirmed with HBsAg subviral particles.

Comparison of HIV-1 drug-resistance genotyping by ultra-deep sequencing and sanger sequencing using clinical samples.

Sanger population sequencing (SPS) is the reference technique to monitor HIV-1-infected patients' therapy. Ultra-deep sequencing (UDS), which allows quantitative detection of drug resistance mutations, may be an alternative method. The study aimed to compare reproducibility and predictions of UDS versus SPS in a routine setting. A control containing low-abundance variants was repeatedly tested and clinical plasma samples from 100 patients were prospectively assayed by SPS and UDS using the Roche 454 system. Complete analysis by UDS was available for 88% of samples with various viral loads and subtypes. Comparison of detection thresholds found that SPS sensitivity was variable. Variations found by UDS between 5% to >20% were detected by SPS in 25% to more than 80% of samples. At the 5% cut-off, disagreements were rare and in most cases UDS detected an additional protease secondary mutation, suggesting a possible resistance to a protease inhibitor according to the 2015 ANRS algorithm. Mutations found on reverse transcriptase by only UDS were often explained by previous therapy. UDS with a variant detection threshold at 5% might allow therapy management with minimal differences compared to population sequencing while providing additional information for further determination of pertinent cutoff values for specific resistance mutations.

Direct-acting antiviral therapy decreases hepatocellular carcinoma recurrence rate in cirrhotic patients with chronic hepatitis C.

BACKGROUND AND AIMS: Arrival of direct-acting antiviral agents against hepatitis C virus with high-sustained virological response rates and very few side effects has drastically changed the management of hepatitis C virus infection. The impact of direct-acting antiviral exposure on hepatocellular carcinoma recurrence after a first remission in patients with advanced fibrosis remains to be clarified. METHODS: 68 consecutive hepatitis C virus patients with a first hepatocellular carcinoma diagnosis and under remission, subsequently treated or not with a direct-acting antiviral combination, were included. Clinical, biological and virological data were collected at first hepatocellular carcinoma diagnosis, at remission and during the surveillance period. RESULTS: All patients were cirrhotic. Median age was 62 years and 76% of patients were male. Twenty-three patients (34%) were treated with direct-acting antivirals and 96% of them achieved sustained virological response. Median time between hepatocellular carcinoma remission and direct-acting antivirals initiation was 7.2 months (IQR: 3.6-13.5; range: 0.3-71.4) and median time between direct-acting antivirals start and hepatocellular carcinoma recurrence was 13.0 months (IQR: 9.2-19.6; range: 3.0-24.7). Recurrence rate was 1.7/100 person-months among treated patients vs 4.2/100 person-months among untreated patients (P=.008). In multivariate survival analysis, the hazard ratio for hepatocellular carcinoma recurrence after direct-acting antivirals exposure was 0.24 (95% confidence interval: 0.10-0.55; P<.001). CONCLUSIONS: Hepatocellular carcinoma recurrence rate was significantly lower among patients treated with direct-acting antivirals compared with untreated patients. Given the potential impact of our observation, large-scale prospective cohort studies are needed to confirm these results.

Hepatitis A outbreak in HIV-infected MSM and in PrEP-using MSM despite a high level of immunity, Lyon, France, January to June 2017.

Since 2016, an increase in the number of hepatitis A cases affecting mainly men who have sex with men (MSM) has been reported in low endemic countries in Europe. We calculated the attack rate in Lyon, France, in populations considered at high-risk: HIV-infected MSM and HIV-negative MSM receiving HIV pre-exposure prophylaxis (PrEP). In these populations, high level of immunity did not prevent the outbreak, indicating that vaccination should be reinforced, particularly in younger individuals.

Hepatitis E virus mutations associated with ribavirin treatment failure result in altered viral fitness and ribavirin sensitivity.

BACKGROUND & AIMS: Ribavirin monotherapy is the preferred treatment for chronic hepatitis E, although occasional treatment failure occurs. We present a patient with chronic hepatitis E experiencing ribavirin treatment failure with a completely resistant phenotype. We aimed to identify viral mutations associated with treatment failure and explore the underlying mechanisms. METHODS: Viral genomes were deep-sequenced at different time points and the role of identified mutations was assessed in vitro using mutant replicons, antiviral assays, cell culture of patient-derived virus and deep-sequencing. RESULTS: Ribavirin resistance was associated with Y1320H, K1383N and G1634R mutations in the viral polymerase, but also an insertion in the hypervariable region comprising a duplication and a polymerase-derived fragment. Analysis of these genome alterations in vitro revealed replication-increasing roles for Y1320H and G1634R mutations and the hypervariable region insertion. In contrast, the K1383N mutation in the polymerase F1-motif suppressed viral replication and increased the in vitro sensitivity to ribavirin, contrary to the clinical phenotype. Analysis of the replication of mutant full-length virus and in vitro culturing of patient-derived virus confirmed that sensitivity to ribavirin was retained. Finally, deep-sequencing of hepatitis E virus genomes revealed that ribavirin is mutagenic to viral replication in vitro and in vivo. CONCLUSIONS: Mutations Y1320H, G1634R and the hypervariable region insertion compensated for K1383N-associated replication defects. The specific role of the K1383N mutation remains enigmatic, but it appears to be of importance for the ribavirin resistant phenotype in this patient. LAY SUMMARY: Ribavirin is the most common treatment for chronic hepatitis E and is mostly effective, although some cases of ribavirin treatment failure have been described. Here, we report on a particular case of ribavirin resistance and investigate the underlying causes of treatment failure. Mutations in the viral polymerase, an essential enzyme for viral replication, appear to be responsible.