Towards the elimination and eradication of hepatitis B

Estimating the attributable fraction of cirrhosis and hepatocellular carcinoma due to hepatitis B and C

A goal of the WHO strategy on the elimination of hepatitis as a public threat is a 65% reduction in the attributable mortality. Deaths related to hepatitis B and C infections are mostly due to decompensated cirrhosis and hepatocellular carcinoma (HCC) but accurately measuring mortality is challenging as death certificates often do not capture the underlying disease. The aim of this collaborative study between European Centre for Disease Prevention and Control (ECDC) and the European Association for the Study of the Liver (EASL) was to assess a WHO-developed protocol to support countries in implementing studies to collect data on the fraction of cirrhosis and hepatocellular carcinoma attributable to hepatitis B and C. Three sentinel sites (in Bulgaria, Norway and Portugal) collected data for patients first admitted or seen in their centres during 2016. Patients with cirrhosis or HCC were identified through patient files or healthcare databases using ICD-10 codes. The proportion of patients with cirrhosis and HCC who tested positive for HBV and HCV were calculated to estimate the aetiological fractions. After the pilot study was completed, each site was asked about the feasibility and acceptability of the protocol. A total of 1249 patients presenting with cirrhosis and/or HCC were evaluated across the three sites. The prevalence of HBV and HCV among cases of cirrhosis showed that in Norway and Portugal, HCV was responsible for about one-quarter of the cases, whereas in Bulgaria, HBV was more common. For HCC, HCV was responsible for more than one-third of cases in Norway and Portugal, while in Bulgaria HBV was more frequent as the underlying cause. Results obtained during the pilot study were comparable to published estimates obtained through statistical modelling or meta-analyses. Several challenges were reported from the sites involved in the pilot including the considerable time needed for reviewing the hospital records and extracting patient data. The pilot demonstrated the feasibility of collecting data on the prevalence of HBV and HCV infection among patients with cirrhosis and HCC in sentinel sites. This method can be used to estimate mortality attributable to HBV and HCV for elimination monitoring. Where easily implementable, sentinel studies are the best way to empower countries, get up-to date data and closely monitor the changes in the attributable fraction at a country level.

Antitumor Effects of Triterpenes in Hepatocellular Carcinoma

BACKGROUND

Triterpenes are a large group of secondary metabolites mainly produced by plants with a variety of biological activities, including potential antitumor effects. Hepatocellular carcinoma (HCC) is a very common primary liver disease spread worldwide. The treatment can consist of surgical intervention, radiotherapy, immunotherapy and chemotherapeutic drugs. These drugs mainly include tyrosine multikinase inhibitors, although their use is limited by the underlying liver disease and displays side effects. For that reason, the utility of natural compounds such as triterpenes to treat HCC is an interesting line of research. No clinical studies are reported in humans so far.

OBJECTIVE

The aim of the present work is to review the knowledge about the effects of triterpenes as a possible coadjuvant tool to treat HCC.

RESULTS

In vitro and xenograft models have pointed out the cytotoxic and anti-proliferative effects as well as improvements in tumor growth and development of many triterpenes. In addition, they have also shown to be chemosensitizing agents when co-administered with chemotherapeutic agents. The mechanisms of action are diverse and involve the participation of mitogen-activated protein kinases, including JNK, p38 MAPK and ERK, and the survival-associated PI3K / Akt signaling pathway. However, no clinical studies are still reported in humans.

CONCLUSION

Triterpenes could become a future strategy to address HCC or at least improve results when administered in combination with chemotherapeutic agents.

Transcriptome Classification Reveals Molecular Subgroups in Patients with Hepatitis B Virus

Hepatitis B virus (HBV) specifically infects hepatocytes, which can cause progressive liver fibrosis and a significantly increased risk of liver cancer. Multiple studies indicated host genetic, virological, and immunological factors could affect the HBV infection. However, the underlying mechanism involved in HBV infection remained unclear. Based on the analysis of gene expression data of 124 HBV patients (GEO accession: GSE84044), molecular subgroups of patients infected with hepatitis B virus were identified in this study, including C1, C2, and C3 groups. The age, fiber, degree of chemical and inflammation, and gene expression difference were also compared among the three sampling groups. Furthermore, the liver index was calculated using 93 liver-specific genes. The liver-specific gene expression in different molecular subgroups of HBV patients was thoroughly analyzed and then was compared with fibrosis and inflammation levels. Results showed that the C2 group was the youngest and the C3 group had the highest degree of fibrosis and inflammation. Enrichment analysis showed that metabolism-related pathways were mainly expressed in the C1 and C2 groups, and inflammation-related pathways and proteoglycans in cancer were highly expressed in the C1 and C3 groups. The liver index was higher in the C2 group than in the C1 and C3 groups, and it was the lowest in the C3 group. Macrophage M1/M2 and neutrophils were significantly different in the three groups. M1 was mainly abundant in the C3 group, and M2 and neutrophils were mainly abundant in the C2 group. This study provides novel information to understand the mechanisms of HBV infection in chronic hepatitis B (CHB) patients.

Treatment of hepatitis B virus with combination therapy now and in the future

Chronic Hepatitis B continues as a significant public health problem despite the availability of safe and effective antivirals and a highly effective protective vaccine. Current therapy, however rarely leads to cure and lifelong therapy is often required, contributing to poor uptake and ongoing morbidity. New insights into the hepatitis B viral life cycle and the host immune response have expanded the potential targets for drug therapies with interesting antiviral candidates and novel immunotherapeutic approaches in early stage development. Yet, HBV persistence is multifactorial - due to an intrahepatic reservoir and ongoing HBV-mediated immune dysregulation, making "cure" unlikely to be realized through even the most efficacious monotherapy. Building on the success seen in the treatment of hepatitis C (HCV) and human immunodeficiency virus (HIV), combination therapy may be an essential strategy to improve efficacy and decrease viral breakthrough. Combinations acting on immune and viral targets are particularly attractive. However, creating synergy while balancing efficacy and safety remains a clear challenge. Various approaches to combination therapy are reviewed, highlighting strengths and challenges of each potential strategy. Overall, combination therapies are attractive as the next step towards cure and are a key strategy for achieving treatment with finite durations and durable endpoints.

2015 Philip S. Portoghese Medicinal Chemistry Lectureship. Curing Hepatitis C Virus Infection with Direct-Acting Antiviral Agents: The Arc of a Medicinal Chemistry Triumph

The development of direct-acting antiviral agents that can cure a chronic hepatitis C virus (HCV) infection after 8-12 weeks of daily, well-tolerated therapy has revolutionized the treatment of this insidious disease. In this article, three of Bristol-Myers Squibb's HCV programs are summarized, each of which produced a clinical candidate: the NS3 protease inhibitor asunaprevir (64), marketed as Sunvepra, the NS5A replication complex inhibitor daclatasvir (117), marketed as Daklinza, and the allosteric NS5B polymerase inhibitor beclabuvir (142), which is in late stage clinical studies. A clinical study with 64 and 117 established for the first time that a chronic HCV infection could be cured by treatment with direct-acting antiviral agents alone in the absence of interferon. The development of small molecule HCV therapeutics, designed by medicinal chemists, has been hailed as "the arc of a medical triumph" but may equally well be described as "the arc of a medicinal chemistry triumph".

The current treatment situation and definitions of a cure for chronic HBV infection

HBV vaccination, while effective in reducing incident chronic disease in endemic regions, will not have the desired impact on the rates of end-stage liver disease in chronically infected persons. Over three decades, IFN-α and nucleoside analogs have reduced the morbidity from the disease. A large reservoir of chronic infection remains. The natural history of HBV infection is still being defined. Understanding the interactions between HBV and the host will be fundamental to achieving higher rates of cure. Curing hepatitis B will require several steps for either eradication, or a functional cure in the host. It is unclear whether covently closed circular DNA chromatin would need to be cleared to cure hepatitis B, or whether low threshold levels would slow the disease.