Einleitung: Zur Behandlung der chronischen Hepatitis C Virus (HCV) Infektion stehen verschiedene interferonfreie Kombinationstherapien zur Verfügung. Die Häufigkeit von resistenzassoziierten Varianten (RAVs) gegenüber direkt antiviral wirksamen Substanzen (DAA) variiert zwischen den HCV Genotypen. In verschiedenen Studien waren präexistente RAVs mit einem virologischen Therapieversagen assoziiert. In dieser Arbeit wurde die Häufigkeit von NS3, NS5A und NS5B RAVs bei therapienaiven und -erfahrenen Patienten untersucht und die Konsequenzen für interferonfreie Therapieoptionen evaluiert.

BACKGROUND & AIMS:The European Association for the Study of the Liver (EASL) guidelines recommend HCV RNA measurements at specific time points during sofosbuvir(SOF)-therapy. However, it remains unclear, how these results should be interpreted. We aimed to analyze whether on-treatment HCV RNA levels predict relapse comparing the CobasAmpliPrep/CobasTaqMan v2.0 (CAP/CTM) and Abbott RealTime HCV (ART) assays. METHODS:Samples were collected from 298 patients (HCV genotypes; GT1-5) at weeks (w) 0, 1, 2, 4, 8, 12, 16, 20 and 24 during SOF-based therapy at two university clinics and tested for HCV RNA level by CAP/CTM and ART. Patients were treated with SOF/ribavirin (RBV) 12/24 w (n=99), pegylated-interferon-alfa (PegIFN)/SOF/RBV 12 w (n=51), SOF/simeprevir (SMV)±RBV 12 w (n=69) or SOF/daclatasvir±RBV 12/24 w (n=79). RESULTS:HCV RNA levels during the first 4weeks of SOF/RBV therapy were significantly lower in GT3 patients who achieved SVR compared with those who relapsed. All GT3 patients with a week 2 result <45IU/ml by CAP/CTM achieved SVR but only 33% of those with ⩾45IU/ml (p=0.0003). Similar results were documented with ART and 60IU/ml as cut-off (SVR: 100% vs. 29%; p=0.0002). In contrast, HCV RNA levels during early treatment phases were not significantly related to relapse in patients treated with other SOF-based regimens. Residual HCV RNA was frequently detected by ART at later stages of therapy. However, SVR rates remained high in these patients. At the end of SOF/SMV±RBV therapy HCV RNA was detectable with ART in 20% of patients, of whom 92% achieved SVR. CONCLUSIONS:HCV RNA levels assessed at week 2 of SOF/RBV therapy can predict relapse in GT3-patients. Detectable HCV RNA results at later stages during SOF-based therapy may occur frequently with the more sensitive ART. However, this should not lead to treatment extension. LAY SUMMARY:We analyzed the predictive value of hepatitis C virus (HCV) RNA levels measured at different time points for treatment efficacy. We found that the level of HCV RNA measured at week 2 of antiviral therapy can be used to predict treatment success in patients with HCV genotype 3 infection treated with sofosbuvir and ribavirin but not in patients treated with other sofosbuvir-based regimens. Low level HCV RNA is frequently detected by the RealTime HCV assay during later stages of antiviral therapy. However, this is not associated with reoccurrence of HCV RNA after the end of treatment.

Type 2 Diabetes (T2D) develops, when β-cell insulin response fails to compensate for insulin resistance. Recent studies reported associations between the IL28B polymorphisms (rs12979860 and rs8099917) and T2D development in Hepatitis C virus (HCV) patients. To identify possible association with T2D independent from virus infection, we investigated both IL28B polymorphisms in T2D patients and healthy controls (HC). No association was found comparing the genotype and allele frequencies of both IL28B polymorphisms between T2D patients and HC. However, higher glucose levels were found in T2D patients carrying the IL28B CT/TT rs12979860 and GT/GG rs8099917 HCV risk genotypes compared to those with the protective CC and TT genotype (p=0.06 and p=0.02, respectively). Moreover, T2D patients with CT/TT rs12979860 HCV risk genotypes possessed significantly higher HbA1c levels than CC carriers (p=0.04). In conclusion, the IL28B HCV risk genotypes may influence glucose homeostasis in T2D patients without HCV.

Einleitung: Prädiktoren für ein Therapieversagen von zugelassenen Kombinationstherapien direkt antiviraler Agenzien (DAAs) für HCV GT1 Infektionen sind das Vorhandensein einer Leberzirrhose sowie das Vorkommen von Resistenz-assoziierten Varianten (RAVs).

Triple therapy of chronic hepatitis C virus (HCV) infection with boceprevir (BOC) or telaprevir (TVR) leads to virologic failure in many patients which is often associated with the selection of resistance-associated variants (RAVs). These resistance profiles are of importance for the selection of potential rescue treatment options. In this study, we sequenced baseline NS3 RAVs population-based and investigated the sensitivity of NS3 phenotypes in an HCV replicon assay together with clinical factors for a prediction of treatment response in a cohort of 165 German and Swiss patients treated with a BOC or TVR-based triple therapy. Overall, the prevalence of baseline RAVs was low, although the frequency of RAVs was higher in patients with virologic failure compared to those who achieved a sustained virologic response (SVR) (7% versus 1%, P = 0.06). The occurrence of RAVs was associated with a resistant NS3 quasispecies phenotype (P<0.001), but the sensitivity of phenotypes was not associated with treatment outcome (P = 0.2). The majority of single viral and host predictors of SVR was only weakly associated with treatment response. In multivariate analyses, low AST levels, female sex and an IFNL4 CC genotype were independently associated with SVR. However, a combined analysis of negative predictors revealed a significantly lower overall number of negative predictors in patients with SVR in comparison to individuals with virologic failure (P<0.0001) and the presence of 2 or less negative predictors was indicative for SVR. These results demonstrate that most single baseline viral and host parameters have a weak influence on the response to triple therapy, whereas the overall number of negative predictors has a high predictive value for SVR.

Single‐nucleotide polymorphisms (SNPs) in the interferon lambda 4 (IFNL4) gene are predictors for treatment success in patients with hepatitis C virus (HCV) infection. For direct‐acting antiviral combinations only weak association with IFNL4 SNPs was observed. Little is known about potential selections of resistance‐associated variants (RAVs) by the IFNL4 genotype. This study analyzed the prevalence of RAVs to currently approved direct‐acting antivirals in a large European population in correlation to SNPs in IFNL4. Samples of 633 patients chronically infected with HCV genotypes 1a (n = 259), 1b (n = 323), and 3 (n = 51) were genotyped for rs12979860 (formerly known as IL28B) and rs368234815. RAVs in NS3, NS5A, and NS5B were detected by population‐based sequencing. In addition, IFNL4 SNPs and NS5A RAVs were analyzed including deep sequencing (n = 109) in an independent replication cohort of HCV genotype 1‐infected patients (n = 201). No significant correlation was found between IFNL4 SNPs and rare and common RAVs within NS3 and NS5B. In contrast, the NS5A RAV Y93H was detected frequently in HCV genotype 1b (14%) and significantly associated with the beneficial IFNL4 SNPs (P < 0.001 and P = 0.002, respectively). Moreover, the presence of Y93H in HCV genotype 1b patients was significantly associated with the second site variant T83M (P < 0.001). Independent factors significantly associated with the presence of Y93H were IFNL4 genotype and high baseline viral load. Conclusion: The NS5A RAV Y93H is significantly associated with the presence of beneficial IFNL4 SNPs and a high baseline viral load in HCV genotype 1‐infected patients, which may explain a lack of correlation or even an inverse correlation of treatment response with IFNL4 genotype in some NS5A inhibitor containing IFN‐free regimens. (Hepatology 2016;63:63–73)

Background: Monitoring HCV RNA levels during treatment is an important tool for managing proteaseinhibitor-based regimens, and different assays used in clinical practice can impact treatment decisions. Objectives: The concordance of three HCV RNA assays was determined, and their impact on treatment decisions assessed using samples from HCV genotype (GT) 1- and GT4-infected patients treated with the NS3/4A inhibitor simeprevir in combination with pegylated interferon-alpha/ribavirin.Study design: Plasma samples collected during the simeprevir Phase III studies QUEST-1 and QUEST-2 (GT1), and RESTORE (GT4) were analyzed with the Roche High-Pure-System COBAS (R) TaqMan (R) HCV v2.0 (HPS), the Roche AmpliPrep COBAS (R) TaqMan (R) HCV v2.0 (CAP), and the Abbott RealTime HCV (ART) assay.Results: In GT1, of the 440 samples, 81% were undetectable (rapid virological response; RVR) by HPS at Week 4, 76% by CAP and 44% by ART. In GT4 (103 samples), RVR rates were 67% by HPS and 24% by ART. HCV RNA <25 IU/mL at Week 4 was observed for 95-96% and 92% GT1 samples and 86% and 74% GT4 samples by HPS/CAP and ART, respectively. At Week 12, assay concordance for undetectability was high in GT1 and GT4, (95-98% and 93%, respectively).Conclusions: While different HCV RNA assays can lead to substantially different RVR rates, a good concordance was observed with a cut-off of 25 IU/mL. Sustained virologic response rates among GT1 patients achieving RVR or <25 IU/mL at Week 4 were high and similar between assays used. At later time points, when viremia is low, assay concordance was high. (C) 2015 Elsevier B.V. All rights reserved.

Different highly effective interferon-free treatment options for chronic hepatitis C virus (HCV) infection are currently available. Pre-existence of resistance associated variants (RAVs) to direct antiviral agents (DAAs) reduces sustained virologic response (SVR) rates by 3-53% in hepatitis C virus (HCV) genotype 1 infected patients depending on different predictors and the DAA regimen used. Frequencies of single and combined resistance to NS3, NS5A and NS5B inhibitors and consequences for the applicability of different treatment regimens are unknown. Parallel population based sequencing of HCV NS3, NS5A and NS5B genes in 312 treatment-naïve Caucasian HCV genotype 1 infected patients showed the presence of major resistant variants in 20.5% (NS3), 11.9% (NS5A), and 22.1% (NS5B) with important differences for HCV subtypes. In NS3, Q80K was observed in 34.7% and 2.1% of subtype 1a and 1b patients, respectively while other RAVs to second generation protease inhibitors were detected rarely (1.4%). Within NS5A RAVs were observed in 7.1% of subtype 1a and 17.6% in subtype 1b infected patients. RAVs to non-nucleoside NS5B inhibitors were observed in 3.5% and 44.4% of subtype 1a and 1b patients, respectively. Considering all three DAA targets all subtype 1a and 98.6% of subtype 1b infected patients were wildtype for at least one interferon free DAA regimen currently available. In conclusion, baseline resistance testing allows the selection of at least one RAVs-free treatment option for nearly all patients enabling a potentially cost- and efficacy-optimized treatment of chronic hepatitis C.

In verschiedenen asiatischen Studien konnte gezeigt werden, dass Mutationen im basalen Core Promotor (BCP) und in der preS-Region des Hepatitis B Virus (HBV) mit der Entwicklung einer Leberfibrose/Zirrhose und/oder eines Hepatozellulären Karzinoms assoziiert sind. Bezüglich Mutationen im Precore-Gen (PC) ist die Datenlage eher kontrovers. Über die Relevanz dieser Mutationen in chronisch HBV-infizierten Patienten in der EU und den USA existieren jedoch nur wenige Daten. Um prognostische Marker auch in diesem Patientenkollektiv zu etablieren, wurde die genotypen-spezifische Prävalenz dieser Mutationen sowie die Bedeutung dieser für den Verlauf der Erkrankung in einer großen europäischen Studienkohorte von Patienten untersucht, die mit den HBV-Genotypen (GT) A bis E infiziert sind.

Einleitung: Zur Therapie der chronischen Infektion mit dem Genotyp (GT) 1 Hepatitis C Virus (HCV) stehen Kombinationen eines nukleotidischen NS5B Inhibitors (Sofosbuvir, SOF) mit einem NS3 Proteaseinhibitor (Simeprevir, SMV) oder einem NS5A-Inhibitor (Daclatasvir, DCV und Ledipasvir, LDV) sowie eine Triple DAA Therapie (NS3-, NS5A- und nicht-nukleosidischer NS5B-Inhibitor) (Paritaprevir, PTV; Ombitasvir, OMV und Dasabuvir, DSV) zur Verfügung. Alternative Optionen sind DCV plus SMV oder Asunaprevir (ASV) für GT1b. In Studien waren die SVR-Raten (sustained virologic response) hoch (> 90%), aber präexistente resistenzassoziierte Varianten (RAVs) führten zur einer SVR Reduktion von 5 – 50%. Es soll untersucht werden, bei wie vielen Patienten eine interferonfreie Therapie unter Ausschluss von präexistenen Resistenzen möglich ist.

Sofosbuvir (SOF) ist ein nukleotidischer Inhibitor der RNA-abhängigen RNA-Polymerase NS5B, der in Deutschland zur Behandlung der chronischen Hepatitis C (HCV) zugelassen ist. Da das aktive Zentrum der NS5B-Polymerase eine hoch-konservierte Region darstellt, hat SOF prinzipiell pangenotypische Wirksamkeit und weist zudem eine hohe Resistenzbarriere auf. Dennoch konnte kürzlich aufgezeigt werden, dass Patienten mit HCV Genotyp (GT)1b-Infektion in den SOF-Zulassungsstudien geringere Ansprechraten als GT 1a-Patienten aufwiesen.

linkage was determined by HCV core and NS5B region sequencing. Clinical and laboratory data was collected longitudinally. Outcomes of interest included spontaneous clearance, determined by two undetectable HCV RNA tests more than 28 days apart, and sustained virological response (SVR). Logistic regression and exact tests were performed, as appropriate, to assess whether duration of infection or IL28B (INFL4) genotype were associated with clearance. Consent was obtained for data retention and analysis. RESULTS: Forty-nine women were determined to have epidemiologically and virologically linked HCV genotype-1b infection. A further 6 aviraemic individuals with detectable HCV antibodies were epidemiologically linked. Among all individuals with linked HCV (n = 55), 39 women consented for analysis (median age 30.2 years; IL28B CC 58%). Eleven (28%) participants spontaneously cleared HCV infection. Of those who failed to spontaneously clear, 22 (79%) commenced treatment using 24–48 weeks (response-guided) pegylated-interferon (PEG) with ribavirin; 1 acute HCV infection was treated with PEG-monotherapy. Five participants were not treated due to comorbidities or loss to follow up. The median duration of infection at treatment initiation was 15 months (IQR 12–22). SVR was achieved in 20 (91%). SVR did not significantly change by IL28B genotype (100% versus 80%, CC versus non-CC, p = 0.486), duration of infection (OR 1.05 per month since date of infection, 95% CI 0.85–1.31, p = 0.663) or length of PEG treatment. Treatment discontinuation due to adverse mental health effects occurred in two cases, however both participants achieved an SVR regardless. CONCLUSION: This is the largest documented single source HCV outbreak in Australia, and required an extensive public health investigation. Notably, PEG-based treatment was highly effective in this cohort who had early chronic HCV infection. In this well characterised outbreak, further research could explore how host selection pressure influences HCV viral evolution, and pathways to clearance or chronicity.