Validation of Baveno VII criteria and other non-invasive diagnostic algorithms for clinically significant portal hypertension in hepatitis delta.

BACKGROUND & AIMS: Non-invasive tests (NITs) for clinically significant portal hypertension (CSPH) require validation in patients with hepatitis D virus (HDV)-related compensated advanced chronic liver disease (cACLD). Therefore, we aimed to validate existing NIT algorithms for CSPH in this context. METHODS: Patients with HDV-cACLD (LSM ≥10 kPa or histological METAVIR F3/F4 fibrosis) who underwent paired HVPG and NIT assessment at Medical University of Vienna or Hannover Medical School between 2013 and 2023 were retrospectively included. Liver stiffness measurement (LSM), von Willebrand factor to platelet count ratio (VITRO), and spleen stiffness measurement (SSM) were assessed. Individual CSPH risk was calculated according to previously published models (ANTICIPATE, 3P/5P). The diagnostic performance of Baveno VII criteria and refined algorithms (Baveno VII-VITRO, Baveno VII-SSM) was evaluated. The prognostic utility of NITs was investigated in the main cohort and an independent, multicenter, validation cohort. RESULTS: Fifty-one patients (HVPG ≥10 mmHg/CSPH prevalence: 62.7%, varices: 42.2%) were included. Patients with CSPH had significantly higher LSM (25.8 [17.2-31.0] vs. 14.0 [10.5-19.8] kPa; p <0.001), VITRO (n = 31, 3.5 [2.7-4.5] vs. 1.3 [0.6-2.0] %/[G/L]; p <0.001), and SSM (n = 20, 53.8 [41.7-75.5] vs. 24.0 [17.0-33.9] kPa; p <0.001). Composite CSPH risk models yielded excellent AUROCs (ANTICIPATE: 0.885, 3P: 0.903, 5P: 0.912). Baveno VII criteria ruled out CSPH with 100% sensitivity and ruled in CSPH with 84.2% specificity. The Baveno VII 'grey zone' (41.1%) was significantly reduced by Baveno VII-VITRO or Baveno VII-SSM algorithms, which maintained diagnostic accuracy. Hepatic decompensation within 2 years only occurred in patients who had CSPH or met Baveno VII rule-in criteria. The prognostic value of NITs was confirmed in the validation cohort comprising 92 patients. CONCLUSIONS: Standalone and composite NIT/diagnostic algorithms are useful for CSPH diagnosis in patients with HDV-cACLD. Thus, NITs may be applied to identify and prioritize patients with CSPH for novel antiviral treatments against chronic hepatitis D. IMPACT AND IMPLICATIONS: Non-invasive tests (NITs) for clinically significant portal hypertension (CSPH) have been developed to identify patients with compensated advanced chronic liver disease (cACLD) at risk of decompensation, but conflicting data has been published regarding the accuracy of liver stiffness measurement (LSM) for the staging of fibrosis in patients infected with hepatitis D virus (HDV). In our study, including 51 patients with HDV-cACLD, LSM- and lab-based NITs yielded high AUROCs for CSPH. Moreover, only patients with CSPH or high non-invasively assessed CSPH risk were at risk of decompensation within 2 years, with the prognostic value of NITs confirmed in a validation cohort. Thus, NITs should be applied and updated in yearly intervals in clinical routine to identify patients with HDV-cACLD at short-term risk of clinical events; NITs may also guide prioritization for novel antiviral treatment options.

Kinetics and predictive value of HBcrAg, HBV RNA and anti-HBc during bulevirtide treatment of chronic HDV-infected patients.

The entry inhibitor bulevirtide (BLV) is a new treatment option for patients with chronic hepatitis D virus (HDV) infection and compensated liver disease. The aim of this study was to investigate the kinetic and predictive value of markers reflecting HBV cccDNA transcriptional activity and host immune response activity during BLV treatment in a real-life cohort of HDV infected patients. Levels of HDV RNA, HBV RNA, hepatitis B core related antigen (HBcrAg) and hepatitis B core antibodies (anti-HBc) were measured in 16 patients before (BL), after three (3M) and six (6M) months of treatment with BLV. All patients received nucleos(t)ide analogue treatment. HDV RNA declined in all patients during treatment. 38% (6/16) showed ≥ 2 log HDV RNA decline from BL to 6M and 11 patients (69%) normalized ALT levels. HBV RNA levels were low and only detectable in two to four patients. HBcrAg levels declined in 75% (12/16) of patients. Median HBcrAg levels declined significantly from BL to 6M (3.75 logU/ml (IQR 2.93-4.78) vs. 3.4 logU/ml (IQR 2-4.68), p=0.002). A similar trend was shown for anti-HBc between BL and 6M. Levels of HBcrAg or anti-HBc did not differ significantly between patients with or without ≥ 2 log HDV RNA decline from BL to 6M.After 6 months treatment with BLV, levels of HBcrAg showed a significant decline, while HBV RNA and anti-HBc levels did not change. Reduction of HBV cccDNA transcriptional activity and immunological effects of antiviral treatment might explain these changes.

Interferon-based treatment of chronic hepatitis D.

Treatment of hepatitis D virus (HDV) infection has been based on the administration of interferon-alfa for more than three decades. First studies to treat HDV-infected patients with type 1 interferons were already performed in the 1980s. Several smaller trials and case series were reported thereafter. During the mid 2000s the use of pegylated interferons for hepatitis D was established. Since then, additional trials were performed in different countries exploring strategies to personalize treatment including extended treatment durations. The overall findings were that about one-quarter to one-third of patients benefit from interferon treatment with persistent suppression of HDV replication. However, only few patients achieve also functional cure of hepatitis B with HBsAg loss. Importantly, several studies indicate that successful interferon treatment is associated with improved clinical long-term outcomes. Still, only a proportion of patients with hepatitis D can be treated with interferons. Even though alternative treatments are currently developed, it is likely that pegylated interferon-alfa will still have an important role in the management of hepatitis D - either alone or in combination. Therefore, better biomarkers are needed to select patients with a high likelihood to benefit from interferon-based treatments. In this review we are discussing basic principles of mode of action of interferon alpha against HDV, summarize previous data on interferon treatment of hepatitis D and give an outlook on potential combinations with novel drugs currently in development.

[Glecaprevir/Pibrentasvir + Sofosbuvir + Ribavirin as a salvage regimen after Sofosbuvir + Velpatasvir + Voxilaprevir re-treatment failure]. / Glecaprevir/Pibrentasvir + Sofosbuvir + Ribavirin als Reserveregime nach Sofosbuvir + Velpatasvir + Voxilaprevir Re-Therapieversagen.

Antiviral therapy of chronic hepatitis C virus (HCV) achieves sustained virological response (SVR) in the majority of patients. Even after initial virological failure, re-treatment with the combination of sofosbuvir+velpatasvir+voxilaprevir (SOF/VEL/VOX) has been established as an effective second line regimen. However, some patients fail to achieve SVR after a second antiviral course with SOF/VEL/VOX. These patients are considered difficult-to-cure. Currently, the optimal regimen for antiviral re-re-treamtent is a matter of debate and European and American guidelines suggest the combination of SOF+glecaprevir/pibrentasvir (G/P) + Ribavirin as a salvage regimen. However, there is only little evidence to support this. In this study, data of two patients with genotype 3 chronic HCV infection, liver cirrhosis and virological failure after re-treatment with SOF/VEL/VOX that successfully achieved SVR with the combination of SOF+G/P ± RBV. Importantly, one patient had Child B cirrhosis to the time of treatment initiation. No adverse events were reported. Thus, our data support the use of SOF + G/P + RBV as a salvage regimen after re-treatment failure with SOF/VEL/VOX.

The transplant cohort of the German center for infection research (DZIF Tx-Cohort): study design and baseline characteristics.

Infectious complications are the major cause of morbidity and mortality after solid organ and stem cell transplantation. To better understand host and environmental factors associated with an increased risk of infection as well as the effect of infections on function and survival of transplanted organs, we established the DZIF Transplant Cohort, a multicentre prospective cohort study within the organizational structure of the German Center for Infection Research. At time of transplantation, heart-, kidney-, lung-, liver-, pancreas- and hematopoetic stem cell- transplanted patients are enrolled into the study. Follow-up visits are scheduled at 3, 6, 9, 12 months after transplantation, and annually thereafter; extracurricular visits are conducted in case of infectious complications. Comprehensive standard operating procedures, web-based data collection and monitoring tools as well as a state of the art biobanking concept for blood, purified PBMCs, urine, and faeces samples ensure high quality of data and biosample collection. By collecting detailed information on immunosuppressive medication, infectious complications, type of infectious agent and therapy, as well as by providing corresponding biosamples, the cohort will establish the foundation for a broad spectrum of studies in the field of infectious diseases and transplant medicine. By January 2020, baseline data and biosamples of about 1400 patients have been collected. We plan to recruit 3500 patients by 2023, and continue follow-up visits and the documentation of infectious events at least until 2025. Information about the DZIF Transplant Cohort is available at https://www.dzif.de/en/working-group/transplant-cohort .

Mice Expressing Minimally Humanized CD81 and Occludin Genes Support Hepatitis C Virus Uptake In Vivo.

Hepatitis C virus (HCV) causes chronic infections in at least 150 million individuals worldwide. HCV has a narrow host range and robustly infects only humans and chimpanzees. The underlying mechanisms for this narrow host range are incompletely understood. At the level of entry, differences in the amino acid sequences between the human and mouse orthologues of two essential host factors, the tetraspanin CD81 and the tight junction protein occludin (OCLN), explain, at least in part, HCV's limited ability to enter mouse hepatocytes. We have previously shown that adenoviral or transgenic overexpression of human CD81 and OCLN facilitates HCV uptake into mouse hepatocytes in vitro and in vivo In efforts to refine these models, we constructed knock-in mice in which the second extracellular loops of CD81 and OCLN were replaced with the respective human sequences, which contain the determinants that are critical for HCV uptake. We demonstrate that the humanized CD81 and OCLN were expressed at physiological levels in a tissue-appropriate fashion. Mice bearing the humanized alleles formed normal tight junctions and did not exhibit any immunologic abnormalities, indicating that interactions with their physiological ligands were intact. HCV entry factor knock-in mice take up HCV with an efficiency similar to that in mice expressing HCV entry factors transgenically or adenovirally, demonstrating the utility of this model for studying HCV infection in vivo IMPORTANCE: At least 150 million individuals are chronically infected with hepatitis C virus (HCV). Chronic hepatitis C can result in progressive liver disease and liver cancer. New antiviral treatments can cure HCV in the majority of patients, but a vaccine remains elusive. To gain a better understanding of the processes culminating in liver failure and cancer and to prioritize vaccine candidates more efficiently, small-animal models are needed. Here, we describe the characterization of a new mouse model in which the parts of two host factors that are essential for HCV uptake, CD81 and occludin (OCLN), which differ between mice and humans, were humanized. We demonstrate that such minimally humanized mice develop normally, express the modified genes at physiological levels, and support HCV uptake. This model is of considerable utility for studying viral entry in the three-dimensional context of the liver and to test approaches aimed at preventing HCV entry.

Host cell mTORC1 is required for HCV RNA replication.

OBJECTIVE: Chronically HCV-infected orthotopic liver transplantation (OLT) recipients appear to have improved outcomes when their immunosuppressive regimen includes a mammalian target of rapamycin (mTOR) inhibitor. The mechanism underlying this observation is unknown. DESIGN: We used virological assays to investigate mTOR signalling on the HCV replication cycle. Furthermore, we analysed HCV RNA levels of 42 HCV-positive transplanted patients treated with an mTOR inhibitor as part of their immunosuppressive regimen. RESULTS: The mTOR inhibitor rapamycin was found to be a potent inhibitor for HCV RNA replication in Huh-7.5 cells as well as primary human hepatocytes. Half-maximal inhibition was observed at 0.01 µg/mL, a concentration that is in the range of serum levels seen in transplant recipients and does not affect cell proliferation. Early replication cycle steps such as cell entry and RNA translation were not affected. Knockdown of raptor, an essential component of mTORC1, but not rictor, an essential component of mTORC2, inhibited viral RNA replication. In addition, overexpression of raptor led to higher viral RNA replication, demonstrating that mTORC1, but not mTORC2, is required for HCV RNA replication. In 42 HCV-infected liver-transplanted or kidney-transplanted patients who were switched to an mTOR inhibitor, we could verify that mTOR inhibition decreased HCV RNA levels in vivo. CONCLUSIONS: Our data identify mTORC1 as a novel HCV replication factor. These findings suggest an underlying mechanism for the observed benefits of mTOR inhibition in HCV-positive OLT recipients and potentiate further investigation of mTOR-containing regimens in HCV-positive recipients of solid organ transplants.

Modulation of HCV reinfection after orthotopic liver transplantation by fibroblast growth factor-2 and other non-interferon mediators.

OBJECTIVE: In HCV infected individuals graft infection occurs shortly after orthotopic liver transplantation (OLT). We aimed to describe the composition of the inflammatory response at this time, how it affects the HCV replication cycle and identify novel proviral and antiviral factors. DESIGN: We used a Luminex assay to quantify 50 inflammatory mediators in sera before and shortly after OLT. In vitro grown HCV based on the JFH-1 isolate were used to characterise the effects of patient sera and individual mediators on HCV. RESULTS: Although the mediator composition is highly variable between individuals, sera drawn immediately post-OLT significantly enhance HCV infectivity compared with control sera from before OLT in about half of the cases. Among 27 non-interferon inflammatory mediators fibroblast growth factor (FGF)-2 stood out as it enhanced HCV RNA replication and release of infectious particles. The effect was concentration-dependent and detectable in dividing and non-dividing cells. Moreover, pharmacological inhibition of FGF-2 receptor signalling abrogated the enhancing effect of FGF-2 and inhibited HCV replication in the absence of serum FGF-2 suggesting that HCV replication is dependent on basal activation of the FGF-2 triggered signalling pathway. Finally, in individuals with chronic HCV infection with high viral load, serum FGF-2 was significantly higher compared with those with low viral load. CONCLUSIONS: Although no single mediator may account for this effect, serum shortly post-OLT enhances HCV infection. FGF-2 is a novel endogenous driver of HCV replication and a potential therapeutic target.

Kinetics and Value of Hepatitis B Core-Related Antigen in Patients with Chronic Hepatitis B Virus Infection during Antiviral Treatment.

BACKGROUND: The hepatitis B core-related antigen (HBcrAg) correlates with HBV DNA in patients with chronic HBV infection without antiviral treatment. Its utility in monitoring patients during and after the cessation of nucleos(t)ide analog (NA) treatment is unknown. METHODS: The levels of HBcrAg were longitudinally determined in two cohorts of chronic HBV-infected patients with (A) newly started NA treatment or (B) after NA cessation during a median follow up (FU) of 60 months or 48 weeks, respectively. The correlation of HBcrAg and HBV DNA and the predictive value for HBeAg seroconversion and HBsAg loss were evaluated. RESULTS: Fifty-six patients with newly-started NA treatment and 22 patients with NA cessation were identified. HBcrAg and HBV DNA strongly correlated before NA treatment (r = 0.77, p < 0.0001) and at virological relapse (0.66, p = 0.0063). At the individual level, the discrepant kinetics of HBcrAg and HBV DNA became evident. During NA treatment, 33% (6/18) and 9% (5/56) of patients showed HBeAg seroconversion or HBsAg loss/HBsAg < 100 IU/mL, respectively. Low levels of HBcrAg were associated with these endpoints. CONCLUSION: HBcrAg levels before antiviral treatment help to identify patients with chances of HBsAg loss or HBeAg seroconversion. However, its utility in replacing quantitative HBV DNA to evaluate treatment efficacy or virological relapse off-treatment is limited.