Outcome of chronic delta hepatitis in Italy: a long-term cohort study

Peginterferon alfa-2a plus tenofovir disoproxil fumarate for hepatitis D (HIDIT-II): a randomised, placebo controlled, phase 2 trial

BACKGROUND

Hepatitis D is the most severe form of chronic viral hepatitis. Treatment guidelines recommend 1 year of peginterferon alfa, which is effective in 25-30% of patients only. Whether prolonged therapy with peginterferon alfa-2a for 96 weeks and combination therapy with tenofovir disoproxil fumarate (TDF) would increase hepatitis D virus (HDV) RNA suppression is unknown. We aimed to explore whether prolonged treatment of HDV with 96 weeks of peginterferon would increase HDV RNA response rates and reduces post-treatment relapses.

METHODS

We did two parallel, investigator-initiated, multicentre, double-blind randomised, controlled trials at 14 study sites in Germany, Greece, Romania, and Turkey. Patients with chronic HDV infection and compensated liver disease who were aged 18 years or older were eligible for inclusion. All patients were HBsAg positive for at least 7 months, anti-HDV positive for at least 3 months, and HDV-RNA positive at the local laboratory at the screening visit. Patients were ineligible if alanine aminotransferase levels were higher than ten times above the upper limit of normal and if platelet counts were lower than 90 000 per μL, or if they had received interferon therapy or treatment with a nucleoside and nucleotide analogue within the preceding 6 months. Patients were randomly assigned by blinded stratified block randomisation (1:1) to receive 180 μg of peginterferon alfa-2a weekly plus either TDF (300 mg once daily) or placebo for 96 weeks. The primary endpoint was the percentage of patients with undetectable HDV RNA at the end of treatment assessed by intention to treat. The trials are registered as NCT00932971 and NCT01088659.

FINDINGS

Between June 24, 2009, and Feb 28, 2011, we randomly assigned 59 HDV RNA-positive patients to receive peginterferon alfa-2a plus TDF and 61 to receive peginterferon alfa-2a plus placebo, including 48 (40%) patients with cirrhosis to the two treatment groups (23 in the peginterferon alfa-2a plus TDF group and 25 in the peginterferon alfa-2a plus placebo group). The primary endpoint was achieved in 28 (48%) of 59 patients in the peginterferon alfa-2a plus TDF group and in 20 (33%) of 61 patients in the peginterferon alfa-2a plus placebo group (odds ratio 1·84, 95% CI 0·86-3·91, p=0·12). We recorded 944 adverse events (459 in the peginterferon alfa-2a plus TDF group and 485 in the peginterferon alfa-2a plus placebo group). The most common adverse events were haematological, behavioural (eg, fatigue), musculoskeletal, influenza-like syndromes, and psychiatric complaints.

INTERPRETATION

Addition of TDF resulted in no significant improvement in HDV RNA response rates at the end of treatment. These findings highlight that alternative treatment options are needed for hepatitis D.

FUNDING

The HepNet Study-House (a project of the German Liver Foundation founded by the German Liver Foundation, the German Ministry for Education and Research, and the German Center for Infectious Disease Research), Hoffmann-La Roche, and Gilead Sciences.

Vibration-controlled transient elastography for the detection of cirrhosis in chronic hepatitis D infection

Noninvasive detection of cirrhosis via vibration-controlled transient elastography (VCTE) has revolutionized the management of chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection. However, VCTE has not been studied in chronic hepatitis D virus (HDV) infection and accuracy remains in question due to the significant hepatic inflammation associated with this infection. Consecutive HBV, HCV and HDV patients who underwent VCTE (2006-2019) were evaluated. Diagnosis of cirrhosis was made via liver biopsy or clinical findings. VCTE was compared with other noninvasive serum fibrosis tests using AUROC curves. The performance of VCTE in HBV/HCV/HDV was also compared. We evaluated 319 patients (HBV-112; HCV-132; HDV-75), 278(87%) patients had histology for evaluation. HDV patients had evidence of higher hepatic inflammation as evidence by aspartate aminotransferase, alanine aminotransferase and histology activity index. Cirrhotic HDV patients had higher mean liver stiffness measurements compared with noncirrhotic patients (29.0 vs 8.3 kPa, P < .0001). VCTE demonstrated excellent diagnostic accuracy for the detection of cirrhosis with an AUROC of 0.90 compared with APRI (0.83), FIB-4 (0.88), AAR (0.73) and RPR (0.85). Performance of VCTE in HDV was comparable with HBV (0.93) and HCV (0.94). At the optimized cut-off value of ≥14.0 kPa for determining cirrhosis in HDV, VCTE had a sensitivity of 0.78, specificity of 0.86, NPV of 0.93 and PPV of 0.64. Hence, VCTE is a useful noninvasive test in HDV for determining cirrhosis despite the presence of significant hepatic inflammation.

High rates of cirrhosis and severe clinical events in patients with HBV/HDV co-infection: longitudinal analysis of a German cohort

Background

Chronic hepatitis delta virus (HDV) infection causes severe liver disease which often leads to cirrhosis and hepatocellular carcinoma (HCC). Aim of this study was to establish the disease severity and prognostic factors for disease outcome by analysing frequencies of clinical events and their correlation with baseline virological and biochemical parameters as well as interferon and nucleos(t)ide analogue treatment choice.

Methods

We studied a single-centre cohort of 49 anti-HDAg-positive patients with HBsAg persistence for at least 6 months. Virological and biochemical parameters, interferon and nucleos(t)ide analogue treatment choice as well as clinical events during follow-up were analysed by retrospective chart review (mean follow-up time 3 years, range 0.25–7.67 years).

Results

Severe clinical events occurred in 11/49 hepatitis D patients, including HCC (8/49), death (8/49) or liver transplantation (2/49). HCCs only occurred secondary to liver cirrhosis and their event rates in this cohort of hepatitis D patients did not differ from a matched HBV mono-infected cohort with comparable frequency of liver cirrhosis. A stepwise multivariate logistic regression revealed low platelet count (p = 0. 0290) and older age (p = 0.0337) correlating most strongly with overall clinical events, while serum HDV RNA positivity at baseline did not correlate with any clinical outcome. Interferon-free but not nucleos(t)ide analogue-free patient care correlated with the occurrence of HCC at logistic regression, although only 3/18 interferon-treated patients demonstrated repeatedly negative HDV PCR results post therapy.

Conclusions

Our data indicate that progressive liver disease at baseline plays a major role as predictive factor for overall clinical outcome of hepatitis D patients. In particular, HCC risk may not be underestimated in hepatitis D virus RNA negative hepatitis D patients with advanced liver fibrosis.

The Delta-4 fibrosis score (D4FS): A novel fibrosis score in chronic hepatitis D

BACKGROUND

Chronic Hepatitis D virus (HDV) infection results in the most severe form of viral hepatitis with a rapid progression to cirrhosis. However, non-invasive fibrosis tests that can accurately predict cirrhosis have not been adequately validated. We aimed to develop a clinically useful non-invasive score that can accurately detect cirrhosis.

MATERIAL AND METHODS

Patients with chronic HDV diagnosed by liver histology or serum PCR were evaluated. Data regarding demographics, laboratory, imaging, vibration-controlled transient elastography (VCTE), and liver biopsy were collected. The total cohort was randomized into a training and validation cohort. The training cohort was used to develop a novel score, the Delta-4 fibrosis score (D4FS) which was then compared to other non-invasive tests in the validation cohort by area under receiver operating characteristics (AUROC).

RESULTS

77 patients with chronic HDV were evaluated: mean age 42.6 (SD:11.1) years, 59.7% male, and 57.1% Asian. The total cohort was then separated into a training (n = 45) and validation (n = 32) cohort with no significant differences in terms of clinical characteristics between the two. From the training cohort, the D4FS was derived from variables of statistical and clinical interest (gamma-glutamyl transpeptidase (GGT), platelet count, alanine aminotransferase (ALT), and liver stiffness measurement (LSM)). The D4FS demonstrated the best AUROC in the validation cohort (0.94) followed by VCTE (0.90), FIB-4 (0.86), APRI (0.81), and AAR (0.71).

DISCUSSION

The D4FS is a clinically useful non-invasive fibrosis score that can accurately detect cirrhosis in patients with chronic HDV infection. Further studies should be performed to further validate clinical utility.

First study of hepatitis delta virus in Algeria: Seroprevalence and risk factors in Setif region (east of Algeria)

Background

No recent data are available on hepatitis delta virus (HDV) prevalence in Algeria. For this reason we conducted an epidemiological study, cross-sectional seroprevalence of HDV in the region of Setif.

Methods

Between 2011 and 2014, sera samples of 500 patients (carrying HBsAg) admitted to the Division of Infectious Diseases Teaching Hospital, Setif (east of Algeria), were tested for anti-HDV-IgG ab (ETI-AB-DeltaK-2).

Results

The prevalence of HDV obtained is estimated at 2.4%. The prevalence ranges from 1% in chronic hepatitis to 11.1% in cirrhotic hepatitis (low endemic area). Seropositivity rate is closely correlated with age (Odds ratio [OR] = 9.98, p = 0.000) and gender (OR = 0.24, p = 0.025); it reaches 58.3% in the age group of 51–60 years and 0% in children (age group 1–15 years); it represents 75% in females and 25% in males. The presence of familial cases of HBsAg positive (OR = 4.54, p = 0.006), the endoscopic procedure (OR = 6.54, p = 0.000) and tattooing (OR = 20, p = 0.000) were found to be the transmission risk factors. A statistically significant relationship was found between the positivity of anti-HDV and advanced liver disease, cirrhosis (OR = 9. 16, p = 0.000). A significant correlation was found between the positivity of anti-HDV with diabetes (OR = 6.83, p = 0.000), obesity (OR = 4.19, p = 0.009) and viral suppression B (OR = 5.69, p = 0.003).

Conclusion

Our results show that HDV infection is low in Algeria. Research for total anti-HDV should be part of the initial assessment of patient care with viral hepatitis B as well as the prevalence of other viruses (hepatitis C [HCV] and HIV). A multicentre study should be carried out to know the importance of HDV infection and identify the risk groups.

Treatment of chronic hepatitis due to hepatitis B and hepatitis delta virus coinfection

An estimated 20-40 million individuals worldwide are infected with hepatitis delta virus (HDV), mostly with rapidly evolving liver disease. Therapy of chronic HDV infection remains an unmet need. To date, only interferon (IFN)-based therapy is recommended for HDV infection and response rates are unsatisfactory; in addition, many patients are intolerant to or ineligible for IFN treatment. In recent years, innovative approaches have been in development, including the following: targeting virus entry into hepatocytes; inhibition of the host enzyme farnesyltransferase by prenylation inhibitors, leading to inhibition of complete virion formation and release; blockade of hepatitis B surface antigen (HBsAg) secretion, inhibiting virus release; and IFN-lambda, which causes fewer adverse effects than IFN-alfa. Clinical trials are ongoing with encouraging preliminary results.

Chronic hepatitis delta: A state-of-the-art review and new therapies

Chronic delta hepatitis is the most severe form of viral hepatitis affecting nearly 65 million people worldwide. Individuals with this devastating illness are at higher risk for developing cirrhosis and hepatocellular carcinoma. Delta virus is a defective RNA virus that requires hepatitis B surface antigen for propagation in humans. Infection can occur in the form of a co-infection with hepatitis B, which can be self-limiting, vs superinfection in a patient with established hepatitis B infection, which often leads to chronicity in majority of cases. Current noninvasive tools to assess for advanced liver disease have limited utility in delta hepatitis. Guidelines recommend treatment with pegylated interferon, but this is limited to patients with compensated disease and is efficacious in about 30% of those treated. Due to limited treatment options, novel agents are being investigated and include entry, assembly and export inhibitors of viral particles in addition to stimulators of the host immune response. Future clinical trials should take into consideration the interaction of hepatitis B and hepatitis D as suppression of one virus can lead to the activation of the other. Also, surrogate markers of treatment efficacy have been proposed.

Acetaldehyde suppresses the display of HBV-MHC class I complexes on HBV-expressing hepatocytes

Hepatitis B virus (HBV) infection and alcoholism are major public health problems worldwide, contributing to the development of end-stage liver disease. Alcohol intake affects HBV infection pathogenesis and treatment outcomes. HBV-specific cytotoxic T lymphocytes (CTLs) play an important role in HBV clearance. Many previous studies have focused on alcohol-induced impairments of the immune response. However, it is not clear whether alcohol alters the presentation of HBV peptide-major histocompatibility complex (MHC) class I complexes on infected hepatocytes resulting in escape of its recognition by CTLs. Hence, the focus of this study was to investigate the mechanisms by which ethanol metabolism affects the presentation of CTL epitope on HBV-infected hepatocytes. As demonstrated here, although continuous cell exposure to acetaldehyde-generating system (AGS) increased HBV load in HepG2.2.15 cells, it decreased the expression of HBV core peptide 18-27-human leukocyte antigen-A2complex (CTL epitope) on the cell surface. Moreover, we observed AGS-induced suppression of chymotrypsin- and trypsin-like proteasome activities necessary for peptide processing by proteasome as well as a decline in IFNγ-stimulated immunoproteasome (IPR) function and expression of PA28 activator and immunoproteasome subunits LMP7 and LMP2. Furthermore, IFNγ-induced activation of peptide-loading complex (PLC) components, such as transporter associated with antigen processing (TAP1) and tapasin, were suppressed by AGS. The attenuation of IPR and PLC activation was attributed to AGS-triggered impairment of IFNγ signaling in HepG2.2.15 cells. Collectively, all these downstream events reduced the display of HBV peptide-MHC class I complexes on the hepatocyte surface, which may suppress CTL activation and the recognition of CTL epitopes on HBV-expressing hepatocytes by immune cells, thereby leading to persistence of liver inflammation.NEW & NOTEWORTHY Our study shows that in HBV-expressing HepG2.2.15 cells, acetaldehyde alters HBV peptide processing by suppressing chymotrypsin- and trypsin-like proteasome activities and decreases IFNγ-stimulated immunoproteasome function and expression of PA28 activator and immunoproteasome subunits. It also suppresses IFNγ-induced activation of peptide-loading complex (PLC) components due to impairment of IFNγ signaling via the JAK-STAT1 pathway. These acetaldehyde-induced dysfunctions reduced the display of HBV peptide-MHC class I complexes on the hepatocyte surface, thereby leading to persistence of HBV infection.

Hepatitis D infection: from initial discovery to current investigational therapies

Hepatitis D is the most severe form of viral hepatitis associated with a more rapid progression to cirrhosis and an increased risk of hepatocellular carcinoma and mortality compared with hepatitis B mono-infection. Although once thought of as a disappearing disease, hepatitis D is now becoming recognized as a serious worldwide issue due to improvement in diagnostic testing and immigration from endemic countries. Despite these concerns, there is currently only one accepted medical therapy (pegylated-interferon-α) for the treatment of hepatitis D with less than desirable efficacy and significant side effects. Due to these reasons, many patients never undergo treatment. However, increasing knowledge about the virus and its life cycle has led to the clinical development of multiple promising new therapies that hope to alter the natural history of this disease and improve patient outcome. In this article, we will review the literature from discovery to the current investigational therapies.

The oncogenic role of hepatitis delta virus in hepatocellular carcinoma

Hepatitis delta virus (HDV) is a small defective virus that needs hepatitis B virus (HBV) to replicate and propagate. HDV infection affects 20-40 million people worldwide and pegylated interferon (PegIFN) is the only recommended therapy. There is limited data on the contribution of HDV infection to HBV-related liver disease or liver cancer. Evidence from retrospective and cohort studies suggests that HBV/HDV coinfection accelerates progression to cirrhosis and is associated with an increased risk of hepatocellular carcinoma (HCC) development compared to HBV monoinfection. Although the life cycle of HDV is relatively well known, there is only ancillary information on the molecular mechanisms that can drive specific HDV-related oncogenesis. No thorough reports on the specific landscape of mutations or molecular classes of HDV-related HCC have been published. This information could be critical to better understand the uniqueness, if any, of HDV-related HCC and help identify novel targetable mutations. Herein, we review the evidence supporting an oncogenic role of HDV, the main reported mechanisms of HDV involvement and their impact on HCC development.

A review on hepatitis D: From virology to new therapies

Hepatitis delta virus (HDV) is a defective virus that requires the hepatitis B virus (HBV) to complete its life cycle in human hepatocytes. HDV virions contain an envelope incorporating HBV surface antigen protein and a ribonucleoprotein containing the viral circular single-stranded RNA genome associated with both forms of hepatitis delta antigen, the only viral encoded protein. Replication is mediated by the host cell DNA-dependent RNA polymerases. HDV infects up to72 million people worldwide and is associated with an increased risk of severe and rapidly progressive liver disease. Pegylated interferon-alpha is still the only available treatment for chronic hepatitis D, with poor tolerance and dismal success rate. Although the development of antivirals inhibiting the viral replication is challenging, as HDV does not possess its own polymerase, several antiviral molecules targeting other steps of the viral life cycle are currently under clinical development: Myrcludex B, which blocks HDV entry into hepatocytes, lonafarnib, a prenylation inhibitor that prevents virion assembly, and finally REP 2139, which is thought to inhibit HBsAg release from hepatocytes and interact with hepatitis delta antigen. This review updates the epidemiology, virology and management of HDV infection.

Clinical outcomes in patients with hepatitis D, cirrhosis and persistent hepatitis B virus replication, and receiving long-term tenofovir or entecavir

BACKGROUND

Suppression of hepatitis B virus (HBV) replication with nucelos(t)ide analogues should be considered for patients with chronic hepatitis D virus (HDV) infection and ongoing HBV replication.

AIM

To verify the clinical outcome after long-term entecavir or tenofovir treatment in patients with advanced fibrosis/cirrhosis, ineligible to peg-interferon therapy.

METHODS

Patients were prospectively followed-up at 3-6 month intervals; measured outcomes were decompensation, hepatocellular carcinoma (HCC), liver transplant and liver related death. HBV monoinfected patients receiving the same treatment served as reference after 1:1 matching by age, gender, platelet count, albumin level, bilirubin and INR.

RESULTS

56 HDV patients (48 with cirrhosis; median follow-up 50 months) were enrolled; all achieved HBV DNA suppression. Death or liver transplant occurred in 19 patients, with a rate (n/1000 patient-months) of 2.92 in HDV patients vs 0.38 in HBV monoinfected patients (P < 0.001); similarly, decompensation occurred at a rate of 1.53 vs 0.13 (P = 0.015), respectively, and the rate of HCC was almost thrice in HDV cohort (3.12 vs 1.12; P = 0.02) Platelet count, Child-Pugh score and marginally HDV infection were associated with HCC development.

CONCLUSION

Patients with HDV infection and advanced liver disease maintain an increased risk of severe clinical events as compared with HBV monoinfected patients, during prolonged HBV DNA suppression with potent NA.

Non-F HBV/HDV-3 coinfection is associated with severe liver disease in Western Brazilian Amazon

The clinical outcome of hepatitis B virus (HBV) infection may be related to host and viral genetic factors, as well as to the type of infection (monoinfection and coinfection). To analyze the distribution/combination of HBV/hepatitis D virus (HDV) genotypes and the associated clinical characteristics, 409 serum samples from patients with chronic HBV (94 of them coinfected by HDV) followed at the Viral Hepatitis Referral Center of Rio Branco, Brazil were enrolled. HBV DNA and HDV RNA were amplified, respectively, by polymerase chain reaction (PCR) and nested PCR using specific primers in the PreC/C region and the S gene, and by reverse-transcription PCR and seminested PCR using specific primers in the delta antigen region and sequenced. The proportion of women (56.1%) was significantly higher than males in this cohort ( P < 0.01). Women were significantly younger (39.8 years; 8-77 years) than males (44.7 years; 12-79 years; P < 0.01). Sixty-eight (18%) patients were infected with HBV-F genotype and 264 (69.8%) with HBV/non-F genotypes. Coinfection by HDV was detected in 23.9% (94 of 409) of this population and was more frequent in male (54.2%, 51 of 94) than in female patients (44.7%, 42 of 94; P = 0.015). HDV-3 was the most prevalent (88.9%) genotype. Almost 70% of HDV-3 coinfected patients were infected with HBV/non-F genotypes. Severe liver disease was diagnosed in 41 patients, 60.9% (25 of 41) of them coinfected with HDV. HBV/HDV coinfection was associated with male sex, age above 30 years, severe liver disease, and increased alanine aminotransferase levels. HBV/HDV-3 coinfection is associated with severe liver disease, in Rio Branco, Brazil.

Pathogenesis of and New Therapies for Hepatitis D

Hepatitis delta virus (HDV) infection of humans was first reported in 1977, and now it is now estimated that 15-20 million people are infected worldwide. Infection with HDV can be an acute or chronic process that occurs only in patients with an hepatitis B virus infection. Chronic HDV infection commonly results in the most rapidly progressive form of viral hepatitis; it is the chronic viral infection that is most likely to lead to cirrhosis, and it is associated with an increased risk of hepatocellular carcinoma. HDV infection is the only chronic human hepatitis virus infection without a therapy approved by the US Food and Drug Administration. Peginterferon alfa is the only recommended therapy, but it produces unsatisfactory results. We review therapeutic agents in development, designed to disrupt the HDV life cycle, that might benefit patients with this devastating disease.

Molecular Signature and Mechanisms of Hepatitis D Virus-Associated Hepatocellular Carcinoma

There is limited data on the molecular mechanisms whereby hepatitis D virus (HDV) promotes liver cancer. Therefore, serum and liver specimens obtained at the time of liver transplantation from well-characterized patients with HDV-HCC (n = 5) and with non-HCC HDV cirrhosis (n = 7) were studied using an integrated genomic approach. Transcriptomic profiling was performed using laser capture-microdissected (LCM) malignant and nonmalignant hepatocytes, tumorous and nontumorous liver tissue from patients with HDV-HCC, and liver tissue from patients with non-HCC HDV cirrhosis. HDV-HCC was also compared with hepatitis B virus (HBV) HBV-HCC alone, and hepatitis C virus (HCV) HCV-HCC. HDV malignant hepatocytes were characterized by an enrichment of upregulated transcripts associated with pathways involved in cell-cycle/DNA replication, damage, and repair (Sonic Hedgehog, GADD45, DNA-damage-induced 14-3-3σ, cyclins and cell-cycle regulation, cell cycle: G₂-M DNA-damage checkpoint regulation, and hereditary breast cancer). Moreover, a large network of genes identified functionally relate to DNA repair, cell cycle, mitotic apparatus, and cell division, including 4 cancer testis antigen genes, attesting to the critical role of genetic instability in this tumor. Besides being overexpressed, these genes were also strongly coregulated. Gene coregulation was high not only when compared with nonmalignant hepatocytes, but also to malignant hepatocytes from HBV-HCC alone or HCV-HCC. Activation and coregulation of genes critically associated with DNA replication, damage, and repair point to genetic instability as an important mechanism of HDV hepatocarcinogenesis. This specific HDV-HCC trait emerged also from the comparison of the molecular pathways identified for each hepatitis virus-associated HCC. Despite the dependence of HDV on HBV, these findings suggest that HDV and HBV promote carcinogenesis by distinct molecular mechanisms.Implications: This study identifies a molecular signature of HDV-associated hepatocellular carcinoma and suggests the potential for new biomarkers for early diagnostics. Mol Cancer Res; 16(9); 1406-19. ©2018 AACR.

Hepatitis delta virus infection in a large cohort of chronic hepatitis B patients in Ethiopia

BACKGROUND & AIMS

Hepatitis D virus (HDV) infection is associated with a more severe outcome in patients with chronic hepatitis B (CHB); however, little is known about the presence of HDV in sub-Saharan Africa. We aimed to determine the prevalence of HDV infection, as well as its clinical, biological and virological characteristics, in a large CHB cohort in Ethiopia.

METHODS

In total, 1267 HIV-negative CHB patients at St. Paul's Hospital Millennium Medical College in Addis Ababa were screened for anti-HDV antibodies using ELISA assays. Confirmed positive samples were further tested for HDV RNA using a consensus commercial real-time RT-PCR assay. HDV genotypes were also determined for RNA-positive samples by nucleotide sequencing followed by phylogenetic analyses. Demographical, clinical and biological data from patients were recorded and compared based on HDV RNA results.

RESULTS

Most patients (n = 748, 59.0%) were men, and the median age was 31 years (interquartile range 26-40). Anti-HDV antibodies were detected in 19 individuals (1.5%), 12 of whom were HDV RNA-positive with a viral load ranging from <2 to >8 log 10 IU/mL. All strains were genotype 1. HDV RNA-positive patients were more likely to have significant liver fibrosis (63.6% vs 24.7%, P = .007) and cirrhosis (45.5% vs 16.4%, P = .024).

CONCLUSIONS

HDV infection is rare in Ethiopia but is associated with more advanced liver fibrosis.

Clinical and virological heterogeneity of hepatitis delta in different regions world-wide: The Hepatitis Delta International Network (HDIN)

BACKGROUND & AIMS

Chronic hepatitis D (delta) is a major global health burden. Clinical and virological characteristics of patients with hepatitis D virus (HDV) infection and treatment approaches in different regions world-wide are poorly defined.

METHODS

The Hepatitis Delta International Network (HDIN) registry was established in 2011 with centres in Europe, Asia, North- and South America. Here, we report on clinical/ virological characteristics of the first 1576 patients with ongoing or past HDV infection included in the database until October 2016 and performed a retrospective outcome analysis. The primary aim was to investigate if the region of origin was associated with HDV replication and clinical outcome.

RESULTS

The majority of patients was male (n = 979, 62%) and the mean age was 36.7 years (range 1-79, with 9% of patients younger than 20 years). Most patients were HBeAg-negative (77%) and HDV-RNA positive (85%). Cirrhosis was reported in 48.7% of cases which included 13% of patients with previous or ongoing liver decompensation. Hepatocellular carcinoma (HCC) developed in 30 patients (2.5%) and 44 (3.6%) underwent liver transplantation. Regions of origin were independently associated with clinical endpoints and detectability of HDV RNA. Antiviral therapy was administered to 356 patients with different treatment uptakes in different regions. Of these, 264 patients were treated with interferon-a and 92 were treated with HBV-Nucs only.

CONCLUSIONS

The HDIN registry confirms the severity of hepatitis delta but also highlights the heterogeneity of patient characteristics and clinical outcomes in different regions. There is an urgent need for novel treatment options for HDV infection.

A Case Report of Hepatocellular Carcinoma 5 Years After HBsAg Loss in Chronic Hepatitis Delta: How Long Surveillance is Required?

BACKGROUND

Hepatitis delta virus infection occurs as acute co-infection or as superinfection in patients with preexisting chronic hepatitis B. Chronic hepatitis delta leads to more severe disease than chronic hepatitis B, with more rapid progression of fibrosis and increased risk of hepatocelullar carcinoma.

CASE REPORT

We report a case of hepatocelullar carcinoma 5 years after spontaneous clearance of Hepatitis B surface antigen in a patient with previous chronic hepatitis delta. He had been diagnosed with acute hepatitis delta superinfection 30 years ago which evolved to chronic delta infection and subsequently development of liver cirrhosis. Despite no specific antiviral treatment, he lost HBsAg persistently with later regression of cirrhosis.

CONCLUSIONS

In patients with cirrhosis due to chronic hepatitis delta who cleared HBsAg with improvement of liver fibrosis by non invasive techniques, it remains unknown how long hepatocelullar carcinoma surveillance has to be maintained.

Hepatitis delta infection - Current and new treatment options

In humans, hepatitis D virus (HDV) infection only occurs in the presence of a concomitant hepatitis B virus (HBV) infection, and induces the most severe form of human viral hepatitis. Even though HDV is spread worldwide and is endemic in some regions, screening and treatment has been often neglected in part due to the lack of an effective therapy. Moreover, HDV prevalence rates are increasing in many countries driven by immigration from areas of high endemicity. Currently, no FDA-approved anti-HDV therapy is available, although interferon (IFN) alpha therapy has demonstrated benefit in a minority of patients. In this review, we present a current view of our understanding of the epidemiology, molecular virology and management of HDV infection. We additionally discuss new treatment approaches in development and describe the most promising results of recent and ongoing clinical trials of these new potential agents.

Hepatitis delta and HIV infection

Viral liver diseases are frequent comorbidities and major contributors to death in HIV-positive individuals on antiretroviral therapy. Although cure of hepatitis C and control of hepatitis B with antivirals avert liver disease progression in most HIV-coinfected patients, the lack of satisfactory treatment for hepatitis delta virus (HDV) infection remains a major threat for developing cirrhosis and liver cancer in this population. In the European Union (EU) and North America, sexual contact has replaced injection drug use that has been the major transmission route for HDV in HIV-positive persons. PegIFNα is the only approved HDV therapy; however, sustained HDV-RNA clearance is achieved by less than 25%. The recent discovery of sodium taurocholate cotransporting polypeptide as the key hepatitis B virus (HBV) and HDV cell entry receptor has opened the door to a new therapeutic era. Indeed, promising results have been released using Myrcludex-B, a sodium taurocholate cotransporting polypeptide inhibitor. More encouraging are data with new classes of HDV blockers, such as prenylation inhibitors (i.e. lonafarnib) and nucleic acid polymers. At this time, sustained suppression of HDV replication is the primary goal of HDV therapy, as it is associated with normalization of liver enzymes and histological improvement. Of note, the use of specific antivirals for HDV must be given along with anti-HBV agents to prevent HBV rebounds following removal of viral interference. The lack of persistent forms of HDV-RNA could provide a unique opportunity for curing hepatitis delta, even without eliminating HBV circular covalently closed DNA. Ultimately, suppression of HDV replication along with hepatitis B surface antigen clearance once drugs are off would be the best reflect of hepatitis delta cure.

Antiviral treatment and liver-related complications in hepatitis delta

Hepatitis delta virus (HDV) is the most severe form of viral hepatitis. Pegylated interferon alfa (PEG-IFNα) is effective in only 25%-30% of patients and is associated with frequent side effects. The aim of this study was to analyze the clinical long-term outcome of hepatitis delta in relation to different antiviral treatment strategies. We studied 136 anti-HDV-positive patients who were followed for at least 6 months in a retrospective single-center cohort (mean time of follow-up, 5.2 years; range, 0.6-18.8). Liver cirrhosis was already present in 62 patients at first presentation. Twenty-nine percent of patients did not receive any antiviral treatment, 38% were treated with interferon alfa (IFNα)-based therapies, and 33% received nucleos(t)ide analogues (NAs) only. Clinical endpoints defined as hepatic decompensation (ascites, encephalopathy, and variceal bleeding), hepatocellular carcinoma, liver transplantation, and liver-related death developed in 55 patients (40%). Patients who received IFNα-based therapies developed clinical endpoints less frequently than those treated with NA (P = 0.02; HR, 4.0) or untreated patients (P = 0.05; HR, 2.2; 17%, 64%, and 44%), respectively, which was significant in both chi-square and Kaplan-Meier analysis. In addition, considering various clinical and virological parameters, IFNα therapy was independently associated with a more benign clinical long-term outcome in multivariate logistic regression analysis (P = 0.04; odds ratio, 0.25; 95% confidence interval, 0.07-0.9). Loss of HDV RNA during follow-up was more frequent in IFNα-treated patients and strongly linked with a lower likelihood to experience liver-related complications.

CONCLUSION

IFNα-based antiviral therapy of hepatitis delta was independently associated with a lower likelihood for clinical disease progression. Durable undetectability of HDV RNA is a valid surrogate endpoint in the treatment of hepatitis delta. (Hepatology 2017;65:414-425).

Performance Characteristics of a New Consensus Commercial Kit for Hepatitis D Virus RNA Viral Load Quantification

Hepatitis D virus (HDV) is responsible for fulminant hepatitis and liver failure and accelerates evolution toward cirrhosis and hepatocellular carcinoma in hepatitis B virus (HBV)-infected patients. To date, treatment relies upon long-term administration of pegylated alpha-interferon with a sustained virological response in 30% of the patients. Very recently, new, promising anti-HDV therapies have been developed and are already being used in clinical trials. HDV RNA viral load (HDVL) monitoring must be an integral part of the management of the infected patients. However, HDV genus is characterized by a high genetic variability into eight genotypes (HDV-1 to -8), and most available in-house or commercial assays are useful for only a limited subset of genotypes. Results of a comparison of the performance of a new kit for HDVL quantification with the consensus in-house assay of the French National Reference Laboratory for HDV developed in 2005 are reported here. A total of 611 clinical samples of all HDV genotypes with various HDVL values, including several consecutive samples over several years from 36 patients, were studied. A specificity, sensitivity, and reproducibility evaluation was conducted using HDV-positive clinical samples, hepatitis A, B, C and E (HAV, HBV, HCV, and HEV, respectively) and HIV mono-infected samples, and the WHO HDV RNA international standard. Overall results were strictly comparable between the two assays (median difference, 0.07 log IU/ml), with high diagnosis precision and capacity. In summary, this new kit showed high performance in detection/quantification of HDVL, regardless of the genotype of the infecting strain used, and seems to be a suitable tool for patient management.

Hepatocarcinogenesis associated with hepatitis B, delta and C viruses

Globally, over half a billion people are persistently infected with hepatitis B (HBV) and/or hepatitis C viruses. Chronic HBV and HCV infection frequently lead to fibrosis, cirrhosis and hepatocellular carcinoma (HCC). Co-infections with hepatitis delta virus (HDV), a subviral satellite requiring HBV for its propagation, accelerates the progression of liver disease toward HCC. The mechanisms by which these viruses cause malignant transformation, culminating in HCC, remain incompletely understood, partially due to the lack of adequate experimental models for dissecting these complex disease processes in vivo.

The hepatitis delta virus: Replication and pathogenesis

Hepatitis delta virus (HDV) is a defective virus and a satellite of the hepatitis B virus (HBV). Its RNA genome is unique among animal viruses, but it shares common features with some plant viroids, including a replication mechanism that uses a host RNA polymerase. In infected cells, HDV genome replication and formation of a nucleocapsid-like ribonucleoprotein (RNP) are independent of HBV. But the RNP cannot exit, and therefore propagate, in the absence of HBV, as the latter supplies the propagation mechanism, from coating the HDV RNP with the HBV envelope proteins for cell egress to delivery of the HDV virions to the human hepatocyte target. HDV is therefore an obligate satellite of HBV; it infects humans either concomitantly with HBV or after HBV infection. HDV affects an estimated 15 to 20 million individuals worldwide, and the clinical significance of HDV infection is more severe forms of viral hepatitis--acute or chronic--, and a higher risk of developing cirrhosis and hepatocellular carcinoma in comparison to HBV monoinfection. This review covers molecular aspects of HDV replication cycle, including its interaction with the helper HBV and the pathogenesis of infection in humans.

Hepatitis B and D viruses replication interference: Influence of hepatitis B genotype

AIM: To study the hepatitis B virus (HBV) and hepatitis D virus (HDV) replication interferences in patients with chronic hepatitis delta infected with different HBV genotypes.

METHODS: We conducted a transversal study including 68 chronic hepatitis delta (CHD) (37 HIV-positive) patients and a control group of 49 chronic hepatitis B (CHB) (22 HIV-positive) patients. In addition, a dynamic follow-up was performed in 16 CHD patients. In all the samples, the surface antigen of hepatitis B (HBsAg) serum titers were analyzed with the Monolisa HBsAg Ultra system (Bio-Rad), using as quantification standard a serial dilution curve of an international HBsAg standard. Serum HBV-DNA titers were analyzed using the Roche Cobas TaqMan (Roche, Barcelona, Spain), and the serum HDV-RNA using an in-house real-time qRT-PCR method, with TaqMan probes. HBV genotype was determined with the line immunoassay LiPA HBV genotyping system (Innogenetics, Ghent, Belgium). In those patients negative for LiPA assay, a nested PCR method of complete HBsAg coding region, followed by sequence analysis was applied.

RESULTS: No differences in the HBV-DNA levels were found in CHB patients infected with different HBV genotypes. However, in CHD patients the HBV-DNA levels were lower in those infected with HBV-A than in those with HBV-D, both in HIV negative [median (IQR): 1.25 (1.00-1.35) vs 2.95 (2.07-3.93) log₁₀ (copies/mL), P = 0.013] and HIV positive patients [2.63 (1.24-2.69) vs 7.25 (4.61-7.55) log₁₀ (copies/mL), P < 0.001]. This was confirmed in the dynamic study of the HBV/HDV patients. These differences induce an under-estimation of HBV-A incidence in patients with CHD analyzed with LiPA assay. Finally, the HBsAg titers reflected no significant differences in CHD patients infected with HBV-A or D.

CONCLUSION: Viral replication interference between HBV and HDV is HBV-genotype dependent, and more evident in patients infected with HBV-genotype A, than with HBV-D or E.

AISF position paper on liver disease and pregnancy

The relationship between liver disease and pregnancy is of great clinical impact. Severe liver disease in pregnancy is rare; however, pregnancy-related liver disease is the most frequent cause of liver dysfunction during pregnancy and represents a severe threat to foetal and maternal survival. A rapid differential diagnosis between liver disease related or unrelated to pregnancy is required in women who present with liver dysfunction during pregnancy. This report summarizes the recommendation of an expert panel established by the Italian Association for the Study of the Liver (AISF) on the management of liver disease during pregnancy. The article provides an overview of liver disease occurring in pregnancy, an update on the key mechanisms involved in its pathogenesis, and an assessment of the available treatment options. The report contains in three sections: (1) specific liver diseases of pregnancy; (2) liver disease occurring during pregnancy; and (3) pregnancy in patients with pre-existing chronic liver disease. Each topic is discussed considering the most relevant data available in literature; the final statements are formulated according to both scientific evidence and clinical expertise of the involved physicians, and the AISF expert panel recommendations are reported.

Seroepidemiology and clinical features of hepatitis delta among HBsAg carriers: a study from Hepatitis Clinic of Iranian Blood Transfusion Organization

BACKGROUND

Hepatitis B is a significant health problem and more than 350 million individuals are infected with hepatitis B virus (HBV) globally. About 5% of these individuals are coinfected with hepatitis D virus (HDV). HBV-HDV coinfection increases the rate of fulminant hepatitis, chronic hepatitis and cirrhosis. This study aimed to evaluate the epidemiology of HDV in individuals positive for hepatitis B surface antigen (HBsAg) who were referred to Tehran Blood Transfusion Hepatitis Clinic from 2011 to 2012.

MATERIALS AND METHODS

HBsAg-positive individuals attending this clinic were tested for anti-HDAg antibodies (anti-HDAbs). All samples positive for anti-HDAb were also tested for detection of HDV RNA by reverse transcription-polymerase chain reaction (RT-PCR). A questionnaire consisting of demographic characteristics and potential risk factors for acquisition of HDV was filled for each individual.

RESULTS

Among 1038 individuals, HBsAg was detected in 660 (63.6%) cases following blood donation and in 378 (36.4%) cases following blood testing. In this study, 23 [2.2%, 95% confidence interval (CI) = 1.3-3.2%] patients were HDV-seropositive. In HDV-seropositive patients, 14 (60.9%, 95% CI = 39.1-78.3%) were positive for HDV RNA. HDV-seropositive cases were more likely to have evidence of severe forms of hepatitis than the group of individuals without anti-HDAb (P < 0.01). Familial history of hepatitis D infection was more observed in HDV-seropositive patients than in individuals negative for anti-HDAb (P < 0.01).

CONCLUSION

The seroprevalence of HDV in HBsAg-positive individuals in this study was about 2% which seems to be lower than the global prevalence of HDV.

Development and evaluation of a baseline-event-anticipation score for hepatitis delta

Hepatitis delta is considered the most severe form of viral hepatitis, but variables associated with disease progression are poorly defined. This study aimed to identify risk factors associated with worse clinical outcome in patients with hepatitis delta and to develop a clinical score to determine their risk of experiencing liver-related morbidity or mortality. We followed 75 HBsAg-anti-HDV-positive patients with hepatitis delta for up to 16 years (median 5 years). The baseline-event-anticipation score (BEA score) was developed based on variables associated with the development of liver-related clinical complications. Age, region of origin, presence of cirrhosis, albumin, INR, hyperbilirubinemia and thrombocytopenia were all associated with the development of an event in the training cohort. The BEA score included age, sex, region of origin, bilirubin, platelets and INR. Points were allocated according to hazard ratios, and three risk groups were defined: BEA-A mild risk, BEA-B moderate risk and BEA-C high risk. Hazard ratios of BEA-B and BEA-C patients for liver-related clinical endpoints were 9.01 and 25.27 vs BEA-A with an area under curve of the receiving operating characteristic curve of 0.88. The accuracy of the BEA score was confirmed in two independent validation cohorts followed in Barcelona (n = 77) and Düsseldorf (n = 62). Delta hepatitis is associated with a very severe long-term outcome. The BEA score is easy to apply and predicts with a very high accuracy the development of liver-related complications in patients with hepatitis delta.

Clinical presentation of hepatitis D in Pakistani children

BACKGROUND

There are limited data on hepatitis D in children. The aim of this study was to assess the clinical presentation of hepatitis D virus (HDV) infection in Pakistani children.

MATERIALS AND METHODS

All pediatric patients (age≤18 years) seen in the clinic with chronic HDV infection and detectable HDV RNA (n=48) were compared with consecutive hepatitis B virus (HBV) monoinfection patients (n=48). A total of 50 patients underwent liver biopsy: 28 in the HDV group and 22 in the HBV group.

RESULTS

There was a male preponderance (85.4%). Significant differences were noted in age (P=0.012), presence of cirrhosis (P=0.004), splenomegaly (P<0.001), esophageal varices (P=0.006), splenic varices (P=0.022), alanine aminotransferase, aspartate aminotransferase and γ-glutamyl transferase levels (P<0.001 each), platelet count (P=0.015), international normalized ratio (P<0.001), severity of inflammation on liver biopsy (P=0.007), and advanced fibrosis (P=0.016) in the two groups, indicating more severe disease in the HDV group. In the HDV group, six patients had normal ALT, of whom three were positive for hepatitis B e antigen (HBeAg) and HBV DNA. HBV DNA was detectable in 50% and HBeAg in 52% of the HDV patients. There were no differences in the severity of liver disease in HBeAg-reactive and HBeAg-nonreactive patients. Six patients with hepatitis D had decompensation at the time of presentation; five were HBV DNA positive and three had reactive HBeAg. Only one patient with HBV monoinfection had decompensation.

CONCLUSION

Children with HDV infection have more aggressive liver disease than HBV monoinfection irrespective of HBeAg status.

Late HDV RNA relapse after peginterferon alpha-based therapy of chronic hepatitis delta

Interferon alpha is the only treatment option for hepatitis delta virus (HDV). Trials investigating the efficacy of pegylated interferon alpha (PEG-IFNa) showed HDV RNA negativity rates of 25-30% 24 weeks after therapy. However, the clinical and virological long-term outcome of HDV-infected patients treated with PEG-IFNa is unknown. We performed a retrospective-prospective follow-up of 77 patients treated for 48 weeks with either PEG-alfa-2a and adefovir (ADV) or either drug alone in the Hep-Net-International-Delta-Hepatitis-Intervention-Study 1 (HIDIT-1) trial. Long-term follow-up data were available for 58 out of 77 patients (75%) with a median time of follow-up of 4.5 (0.5-5.5) years and a median 3 visits per patient. Patients treated with ADV alone received retreatment with PEG-IFNa (48% versus 19%; P = 0.02) more often. Hepatitis B virus surface antigen (HBsAg) became negative in six PEG-IFNa-treated patients until the end of long-term follow-up (10%). Sixteen patients tested HDV RNA-negative 6 months after PEG-IFNa treatment who were entered in the long-term follow-up study. Out of these, nine individuals tested HDV RNA-positive at least once during further long-term follow-up, with seven patients being HDV RNA-positive at the most recent visit. Clinical endpoints (liver-related death, liver transplantation, hepatic decompensation, hepatocellular carcinoma) were observed in three PEG-IFNa-treated (8%) and three ADV-treated (14%) patients during posttreatment long-term follow-up with an overall annual event rate of 2.5% (4.9% in cirrhosis). Sequencing confirmed the reappearance of pretreatment virus strains in all cases.

CONCLUSION

Late HDV RNA relapses may occur after PEG-IFNa therapy of hepatitis delta and thus the term sustained virological response should be avoided in HDV infection. The annual posttreatment rate of clinical events in hepatitis delta patients eligible for PEG-IFNa therapy is about 2.5% and 4.9% in patients with cirrhosis.

Interferon alpha-2b therapy in chronic hepatitis delta

BACKGROUND

Approximately 5% of hepatitis B virus (HBV) carriers are coinfected with hepatitis D virus (HDV). HBV/HDV coinfection is a major cause of cirrhosis and end stage liver disease in chronic HBsAg carriers. The only approved therapy for chronic hepatitis delta is interferon alpha (IFN α) in either pegylated or conventional forms. Although higher doses and longer durations of IFN α therapy in HBV/HDV coinfected patients are currently applied, yet treatment response is low.

OBJECTIVES

We aimed to determine the efficacy of IFN α-2b therapy in patients with HBV/HDV coinfection.

PATIENTS AND METHODS

In this cross sectional study, 20 HBsAg carriers with positive Anti-HDVAb and RT-PCR for HDV RNA were recruited and treated for three year duration with 5 million units (MU) of IFN α-2b, three times weekly or one year with 5 MU of IFN α-2b daily. Sustained virological response (SVR) was defined as a negative qualitative HDV RT-PCR, 6 months after treatment cessation.

RESULTS

Overall, 3 (15%) subjects achieved SVR, 10 cases (50%) relapsed after treatment cessation and 7 (35%) patients did not clear HDV during the treatment.

CONCLUSIONS

HDV coinfection with HBV had very low response rate to high doses and long durations of IFN α-2b therapy.

Development of a reverse transcription quantitative real-time PCR-based system for rapid detection and quantitation of hepatitis delta virus in the western Amazon region of Brazil

The hepatitis delta virus (HDV) is a pathogen that causes a severe and rapidly progressive disease of hepatocytes. The measurement of viral load in the peripheral blood of patients with HDV infections is important for diagnosis, treatment monitoring, and support for follow-up studies of viral replication during the course of the disease. This study reports the development of an assay capable of detecting and quantifying the abundance of HDV particles in serum samples, based on reverse-transcription quantitative PCR (RT-qPCR). Two standards for calibration were produced for determining the viral load of HDV: a cDNA cloned into a linear plasmid and a transcribed RNA. For validating this assay, 140 clinical samples of sera were used, comprising 100 samples from patients who tested positive for anti-HDV and hepatitis B virus surface antigen (HBsAg) by ELISA; 30 samples from blood donors; 5 samples monoinfected with hepatitis B virus (HBV); and 5 samples monoinfected with hepatitis C virus (HCV). The HDV RT-qPCR assay performed better when calibrated using the standard based on HDV cDNA cloned into a linear plasmid, yielding an efficiency of 99.8% and a specificity of 100% in the in vitro assays. This study represents the first HDV RT-qPCR assay developed with clinical samples from Brazil and offers great potential for new clinical efficacy studies of antiviral therapeutics for use in patients with hepatitis delta in the western Amazon region.

Effect of tenofovir with and without interferon on hepatitis D virus replication in HIV-hepatitis B virus-hepatitis D virus-infected patients

The effect of tenofovir (TDF) alone or in combination with interferon on hepatitis D virus (HDV) replication is poorly characterized in patients infected with human immunodeficiency virus (HIV), hepatitis B virus (HBV), and HDV. We analyzed triinfected patients undergoing treatment with either TDF alone (n=13) or including interferon (IFN) at some point during TDF therapy (TDF+IFN, n=4). Linear mixed-effect models were used to estimate the mean change from baseline of HDV-RNA and hepatitis surface antigen (HBsAg) levels during treatment. Patients were followed for a median 31.6 (25-75%-tile: 15.0-47.4) months. In the TDF+IFN group, three initiated IFN-based therapy after a median of 21.7 months (range=10.5-24.9) of lamivudine (LAM)+TDF, while the remaining patient had 46.8 months of prior LAM exposure. Significant decreases in HDV-RNA were observed in both groups [TDF alone: -0.380 log10 copies/ml per year (95% CI: -0.557, -0.202) vs. TDF+IFN: -1.325 log10 copies/ml per year (95% CI: -1.931, -0.720)], while the HDV-RNA decline overall was significantly faster in patients with TDF+IFN (p=0.002). Accordingly, two patients achieved HDV-RNA below the limit of quantification (LOQ: <1,000 copies/ml) and one near LOQ (1450 copies/ml), all concomitantly treated with interferon. There were no significant changes in HBsAg levels for either group [TDF alone: -0.008 log10 IU/ml per month (95% CI: -0.019, 0.004), TDF+IFN:-0.011 log10 IU/ml per month (95% CI: -0.037, 0.015)] and no significant difference in slope between treatment groups (p=0.8). Interferon therapy might be more effective after extended previous anti-HBV antiviral exposure among triinfected patients; however, the long-term implications of these findings remain unknown.

High prevalence and significance of hepatitis D virus infection among treatment-naïve HBsAg-positive patients in Northern Vietnam

Background

Hepatitis D virus (HDV) infection is considered to cause more severe hepatitis than hepatitis B virus (HBV) monoinfection. With more than 9.5 million HBV-infected people, Vietnam will face an enormous health burden. The prevalence of HDV in Vietnamese HBsAg-positive patients is speculative. Therefore, we assessed the prevalence of HDV in Vietnamese patients, determined the HDV-genotype distribution and compared the findings with the clinical outcome.

Methods

266 sera of well-characterized HBsAg-positive patients in Northern Vietnam were analysed for the presence of HDV using newly developed HDV-specific RT-PCRs. Sequencing and phylogenetic analysis were performed for HDV-genotyping.

Results

The HDV-genome prevalence observed in the Vietnamese HBsAg-positive patients was high with 15.4% while patients with acute hepatitis showed 43.3%. Phylogenetic analysis demonstrated a predominance of HDV-genotype 1 clustering in an Asian clade while HDV-genotype 2 could be also detected. The serum aminotransferase levels (AST, ALT) as well as total and direct bilirubin were significantly elevated in HDV-positive individuals (p<0.05). HDV loads were mainly low (<300 to 4.108 HDV-copies/ml). Of note, higher HDV loads were mainly found in HBV-genotype mix samples in contrast to single HBV-infections. In HBV/HDV-coinfections, HBV loads were significantly higher in HBV-genotype C in comparison to HBV-genotype A samples (p<0.05).

Conclusion

HDV prevalence is high in Vietnamese individuals, especially in patients with acute hepatitis B. HDV replication activity showed a HBV-genotype dependency and could be associated with elevated liver parameters. Besides serological assays molecular tests are recommended for diagnosis of HDV. Finally, the high prevalence of HBV and HDV prompts the urgent need for HBV-vaccination coverage.

Prevalence of hepatitis delta virus (HDV) infection in chronic hepatitis B patients with unusual clinical pictures

BACKGROUND

Probably 5% of the HBV carriers have HDV super infection. The risk of fulminant hepatitis, cirrhosis and hepatocellular carcinoma is higher in superinfection than the settings when HBV is alone.

OBJECTIVES

The aim of this study was to evaluate the prevalence of HDV in Iranian HBV isolates and to compare their clinical and virological pictures as well as their HDV genetic variations with other worldwide isolates.

PATIENTS AND METHODS

81 carriers with positive results for HBsAg with upper limit ranges of ALT and low or undetectable levels of HBV viral load who did not respond to HBV therapy were selected. After RT amplification of HDV Delta antigen, direct sequencing and phylogenetic study were performed to explore the genotype(s) and nucleotide/amino acid variations.

RESULTS

12 (14.8%) patients had positive results for both HDV RNA and anti-HDV. The mean ALT level was higher in HDV positive patients (75.9 U/ML) than HBV-mono-infected individuals; however, the mean HBV viral load was lower in coinfected patients than HBV-mono-infected patients. Phylogenetically, genotype I was the only detected genotype, and the most closely related isolates were of Turkish, Italian and Mongolian origin. Within the delta Ag, there were 326 nucleotide mutations, of which 111 and 215 were silent and missense, respectively. The total number of amino acid substitution was 148; most were located in known functional/epitopic domains. There was no correlation between the numbers of amino acid mutations, with clinical, virological status of the patients.

CONCLUSIONS

HDV should be suspected in HBV carriers with unusual clinical and virological pictures. Relatedness of Iranian HDV isolates to Italian and Turkish sequences proposed a common Caucasian origin for the distribution of HDV genotype I in this ethnic group.

Hepatitis viruses (other than hepatitis B and C viruses) as causes of hepatocellular carcinoma: an update

Chronic hepatitis B and C virus infections are universally accepted as causes of hepatocellular carcinoma in humans. Hepatitis A and E viruses cause only acute self-limiting infections of the liver. Of the remaining hepatitis viruses - Delta hepatitis, hepatitis G (GB-C), TT and SEN - all have at some time been incriminated as causes of hepatocellular carcinoma. Delta hepatitis virus requires helper functions from hepatitis B virus to become invasive. Chronic Delta/hepatitis B viral co-infection runs a more severe course than that resulting from chronic hepatitis B virus infection alone, with progression to cirrhosis being more likely and more rapid. A substantial majority of the early studies did not find an increased incidence of hepatocellular carcinoma in co-infected individuals. But more recently, an increased incidence of the tumour has been recorded more often than no increase. Further studies are needed to draw a firm conclusion with regard to the hepatocarcinogenic effect of dual Delta/hepatitis B virus co-infection. With one exception, no published study (of 13) has incriminated chronic infection with hepatitis G virus as a cause of hepatocellular carcinoma. The dissenting study, published in 1999, was the only one performed in the United States. Fewer studies of the hepatocarcinogenic effect of TT virus have been performed. Apart from one study, published in 1999, no convincing evidence is available that supports a causal role for TT virus in hepatocarcinogenesis. The exception was in Japanese patients with high hepatitis C viral loads but independent of chronic hepatitis C virus infection. No evidence has been produced to indicate that SEN virus causes hepatocellular carcinoma.

Treatment options for hepatitis delta virus infection

The hepatitis D virus (HDV), the smallest virus known to infect man, causes the most severe form of chronic viral hepatitis, hepatitis delta. It is estimated that about 15 to 20 million people are suffering from chronic HDV infection. HDV is a defective satellite virus depending on the hepatitis B surface antigen (HBsAg) for transmission. Chronic hepatitis delta is associated with a rapid progression of liver fibrosis and a high prevalence of liver cirrhosis, even in younger patients. Immunization against hepatitis B virus (HBV) protects from HDV infection, but there is no specific vaccine against HDV available for HBsAg-positive individuals. Treatment options for hepatitis delta patients are limited. So far, only interferon-alpha has shown an antiviral efficacy against HDV. Recent trials showed sustained virological response rates concerning HDV in 25 %-30 % of patients treated with pegylated interferons. HDV is dominant over HBV in the majority of cases, but HBV DNA-positive subjects should be treated with HBV polymerase inhibitors. Combination therapy of pegylated interferon-alpha and adefovir showed a more pronounced HBsAg decline, but the exact role of combination therapies in hepatitis delta requires further investigation. Alternative future treatment strategies may include prenylation inhibitors and HBV entry inhibitors, which are in early clinical development.

Treatment of chronic hepatitis delta virus with peg-interferon and factors that predict sustained viral response

AIM: To observe the efficacy of peg-interferon in the treatment of hepatitis delta virus (HDV) and to identify the factors that would be predictive of the sustained viral response (SVR).

METHODS: This prospective study was conducted in Medical Unit IV of the Liaquat University of Medical and Health Sciences Hospital Jamshoro from June 2008 to September 2011. This study cohort included all patients of either sex who presented during this time with hepatitis B surface antigen positivity, hepatitis B virus DNA > 20 000 IU/mL, serum glutamic pyruvic transaminase (SGPT) > 2(upper limit of normal), HDV-RNA positivity with fibrosis stage ≥ 2. Informed consent was obtained from each of these individuals. Patients were diagnosed with hepatitis D on the basis of detectable viral antibodies and the presence of HDV-RNA in their serum. A liver biopsy was performed in all cases and fibrosis staging was performed in accordance with the METAVIR scoring system. All eligible patients were administered peg-interferon at a weekly dosage of 1.5 μg/kg body weight for 48 wk. HDV-RNA was assayed at the end of this treatment period and again at 24 wk later. A biochemical response was determined by a normalization of SGPT at the end of the treatment or during follow up. The end of treatment response was defined by a HDV-RNA negative status. A sustained virological response was defined by undetectable serum HDV-RNA at six months after the end of treatment.

RESULTS: Among the 277 patients enrolled in our present study, 238 completed a course of peg-interferon therapy of which 180 (75.6%) were male and 58 (24.4%) female. Biochemical responses were achieved in 122/238 (51.3%) patients. End of treatment responses were achieved in 71/238 (29.8%) cases. A SVR was achieved in 70 of these patients (29.4%). A strong association was found between the SVR and the end of treatment responses (P = 0.001), biochemical responses (P = 0.001) and the degree of fibrosis (P = 0.002).

CONCLUSION: Peg-interferon therapy can induce remission in nearly one third of patients harboring HDV.

Current concept in the pathophysiology of hepatitis delta infection

Hepatitis delta virus (HDV) is a unique human virus, showing similarities with plant viroids. Although impressive knowledge on virus structure and replication has been achieved, several questions like HBV/HDV interaction and post translational modifications of HD antigens remain to be answered. Potential targets for therapeutic strategies are now emerging. To date, eight major genotypes of the HDV have been identified. The HDV-1 is the prevailing genotype in Europe, but migration phenomena may change this profile. Immune response is likely to play an important role in the pathogenesis of HDV-induced liver disease; few data are available on T cells response either during infection and therapy. HDV usually suppresses HBV replication; recent studies show as viral dominances may change over time. Delta infection leads to severe liver disease, with different patterns of progression to liver fibrosis and decompensation. Beside the association between HDV/HBV and HCC is demonstrated a risk specifically related to HDV remains controversial.

HBeAg-positive hepatitis delta: virological patterns and clinical long-term outcome

BACKGROUND AND AIMS

The presence of the hepatitis B virus (HBV)-eAg in patients with hepatitis B is associated with higher HBV replication and with an increased risk to develop liver-related clinical endpoints defined as liver related death, liver transplantation, development of hepatocellular carcinoma and hepatic decompensation. The aim of this study was to investigate the role of HBeAg in patients co-infected with the hepatitis D virus (HDV).

METHODS

We studied virological markers of HBV and HDV infection and as well as biochemical and clinical features of liver disease in a cohort of 534 anti-HDV-positive patients. In addition, we compared the clinical long-term outcome of HBeAg-positive HDV-infected patients with HBeAg-negative control patients matched for age, gender and baseline-MELD score.

RESULTS

HBeAg-positive hepatitis delta was detected in 71 of 534 patients (13.3%). HBeAg positivity was associated with a higher biochemical disease activity and higher HBsAg levels in HDV co-infected patients. Sixty one per cent of the HBeAg-positive HDV-infected patients presented with HBV DNA levels below 2000 IU/ml, at least once during follow-up. Both HBeAg-positive and -negative patients showed a similar severe clinical long-term course with about half of the patients developing a liver-related clinical complication after a median follow-up period of 51 months (range: 9-193 months).

CONCLUSIONS

HBV DNA levels are low in both HBeAg-negative and HBeAg-positive patients suggesting suppressive effects of HDV on HBV irrespective of the phase of HBV infection. The clinical long-term outcome of HBeAg-positive patients is not different to HBeAg-negative patients infected with the HDV.

Interferon-α for patients with chronic hepatitis delta: a systematic review of randomized clinical trials

BACKGROUND

Hepatitis delta virus (HDV) infection therapy is unclear. This systematic analysis aimed to clarify the evidence on the efficacy of interferon (IFN)-α-based therapy in HDV.

METHODS

We performed a systematic search on electronic databases including MEDLINE (1970 to January 2011), Web of Science, The Cochrane Library and ClinicalTrials.gov. Randomized clinical trials (RCTs) comparing IFN-α-based therapy with either another drug, placebo or no intervention were included. We excluded paediatric studies. We calculated relative risks (RRs) for comparison of treatment options on the primary outcome measure, which was defined as undetectable levels of HDV RNA and normal alanine aminotransferase at end of treatment (EOT; 1 year).

RESULTS

Nine RCTs were included. Seven trials evaluated the treatment with IFN-α (n=132). The remaining two trials evaluated treatment with pegylated (PEG)-IFN-α (n=45). We found that 1-year treatment with high-dose IFN-α achieved better primary outcome rates than with PEG-IFN-α (RR=4.14, 95% CI 1.00, 17.14). Data for 1-year treatment with low-dose IFN-α compared with PEG-IFN-α were similar (RR=2.83, 95% CI 0.65, 12.40), as were low-dose IFN-α versus high-dose IFN-α (RR=0.68, 95% CI 0.31, 1.50). High-dose IFN-α and PEG-IFN-α reached similar HDV RNA suppression 24 weeks after EOT (RR=1.00, 95% CI 0.51, 1.97). None of the 55 patients assigned to no intervention obtained undetectable levels of HDV RNA and only one patient achieved normalization of alanine aminotransferase level.

CONCLUSIONS

Based on available RCTs, 1-year high-dose IFN-α monotherapy appears to be more effective than PEG-IFN-α for treatment of HDV patients, with efficacy rates of approximately 30%. There is a lack of head-to-head comparisons. Combination therapies and longer treatment duration need to be investigated.

Molecular and clinical aspects of hepatitis D virus infections

Hepatitis D virus (HDV) is a defective virus with circular, single-stranded genomic RNA which needs hepatitis B virus (HBV) as a helper virus for virion assembly and infectivity. HDV virions are composed of a circular shape HDV RNA and two types of viral proteins, small and large HDAgs, surrounded by HBV surface antigen (HBsAg). The RNA polymerase II from infected hepatocytes is responsible for synthesizing RNAs with positive and negative polarities for HDV, as the virus does not code any enzyme to replicate its genome. HDV occurs as co-infection or super-infection in up to 5% of HBsAg carriers. A recent multi-center study highlighted that pegylated interferon α-2a (PEG-IFN) is currently the only treatment option for delta hepatitis. Nucleotide/nucleoside analogues, which are effective against HBV, have no relevant effects on HDV. However, additional clinical trials combining PEG-IFN and tenofovir are currently ongoing. The molecular interactions between HDV and HBV are incompletely understood. Despite fluctuating patterns of HBV viral load in the presence of HDV in patients, several observations indicate that HDV has suppressive effects on HBV replication, and even in triple infections with HDV, HBV and HCV, replication of both concomitant viruses can be reduced. Additional molecular virology studies are warranted to clarify how HDV interacts with the helper virus and which key cellular pathways are used by both viruses. Further clinical trials are underway to optimize treatment strategies for delta hepatitis.