Current status of hepatitis delta

The prevalence of HDV among HBsAg-positive populations with and without HIV-1 in China

BACKGROUND

Existing research has provided evidence of changes in hepatitis delta virus (HDV) prevalence worldwide. This study aimed to investigate the prevalence and molecular characteristics of HDV to elucidate its spread in China.

METHODS

A total of 3,000 samples were collected from 2,241 HBV monoinfections and 759 HBV/HIV-1 coinfections across 13 sites in northern, southern, western, and southwestern China. Serological and virological prevalence were determined by detecting anti-HDV antibodies and HDV RNA.

RESULTS

The study revealed a 2.63% (95% CI: 2.06-3.21) seroprevalence of HDV among HBV infections in China, exhibiting regional variation. HDV seroprevalence was notably higher at 7.91% (95% CI: 5.98-9.83) in HBV and HIV-1 coinfections. Region and HIV-1 infection were identified as risk factors for HDV infection. Virological prevalence was 0.67% (95% CI: 0.38-0.96) in HBV infections and 2.24% (95% CI: 1.18-3.29) in HBV/HIV-1 coinfections. The predominant HDV genotype in China was HDV-2a, followed by HDV-1. Participants with anti-HDV positivity demonstrated significantly higher proportions of abnormal liver dysfunction and elevated HBV DNA load (P < 0.001) compared to anti-HDV-negative participants.

CONCLUSIONS

This study highlights the HDV epidemic in China, sheds light on its geographical distribution and high-risk populations, and provides insights for developing strategies to manage the spread of HDV in the country.

Prevalence of hepatitis D virus infection among patients with chronic hepatitis B infection in a tertiary care centre in Thailand

Knowledge about the epidemiology of hepatitis D virus (HDV) is essential for effective screening and management. Our study aimed to update the prevalence of HDV infection among patients with hepatitis B virus (HBV) infection at hepatology clinics in Thailand. We enrolled HBV-infected patients from hepatology clinics at King Chulalongkorn Memorial Hospital, Bangkok, Thailand, between June 2022 and November 2023. Demographic, biochemical characteristics, and liver-related complications (LRC), including cirrhosis and hepatocellular carcinoma, were reviewed. The competitive enzyme and chemiluminescence immunoassays were used to detect anti-HDV antibodies. Real-time polymerase chain reaction (RT-PCR) was used to test for HDV RNA in anti-HDV-positive patients. The HDV genotype was identified in detectable HDV RNA samples. Of the 702 enrolled patients, four (0.6%) had positive and equivocal for both anti-HDV tests. Two (50.0%) of the four patients tested positive for HDV RNA and genotype 1 was identified; one had multiple risk factors. Anti-HDV seroprevalence was not significantly different between patients with and without LRC. In conclusion, HDV co-infection is less common in Thailand than globally. Additionally, our study identified genotype 1, the predominant HDV genotype worldwide, and observed co-infection even without LRC.

HERACLIS-HDV cohort for the factors of underdiagnosis and prevalence of hepatitis D virus infection in HBsAg-positive patients

BACKGROUND AND AIMS

Hepatitis D virus (HDV) underdiagnosis remains common. We assessed the HDV screening and prevalence rates in HBsAg-positive patients seen at tertiary liver centres throughout Greece as well as factors affecting HDV diagnosis.

METHODS

All adult HBsAg-positive patients seen within the last 5 years were included. Non-screened patients who visited or could be recalled to the clinics over a 6-month period were prospectively tested for anti-HDV.

RESULTS

Of 5079 HBsAg-positive patients, 53% had anti-HDV screening (41% before and 12% after study initiation). Pre-study (8%-88%) and total screening rates (14%-100%) varied widely among centres. Screening rates were associated with older age, known risk group, elevated ALT, centre location and size and period of first visit. Anti-HDV prevalence was 5.8% without significant difference in patients screened before (6.1%) or after study initiation (4.7%, p = 0.240). Anti-HDV positivity was associated with younger age, parenteral drug use, born abroad, advanced liver disease and centre location. Overall, HDV RNA detectability rate was 71.6% being more frequent in anti-HDV-positive patients with elevated ALT, advanced liver disease and hepatitis B therapy.

CONCLUSIONS

Anti-HDV screening rates and recall capabilities vary widely among Greek liver clinics being higher in HBsAg-positive patients of known risk group with active/advanced liver disease seen at smaller centres, while non-medical factors are also important. Anti-HDV prevalence varies throughout Greece being higher in patients born abroad with younger age, parenteral drug use and advanced liver disease. Viremia is more frequently but not exclusively detected in anti-HDV-positive patients with elevated ALT and advanced liver disease.

Hepatocellular carcinoma: The virus or the liver?

Hepatocellular carcinoma (HCC) represents a major public health problem being one of the most common causes of cancer-related deaths worldwide. Hepatitis B (HBV) and C viruses have been classified as oncoviruses and are responsible for the majority of HCC cases, while the role of hepatitis D virus (HDV) in liver carcinogenesis has not been elucidated. HDV/HBV coinfection is related to more severe liver damage than HBV mono-infection and recent studies suggest that HDV/HBV patients are at increased risk of developing HCC compared to HBV mono-infected patients. HBV is known to promote hepatocarcinogenesis via DNA integration into host DNA, disruption of molecular pathways by regulatory HBV x (HBx) protein and excessive oxidative stress. Recently, several molecular mechanisms have been proposed to clarify the pathogenesis of HDV-related HCC including activation of signalling pathways by specific HDV antigens, epigenetic dysregulation and altered gene expression. Alongside, ongoing chronic inflammation and impaired immune responses have also been suggested to facilitate carcinogenesis. Finally, cellular senescence seems to play an important role in chronic viral infection and inflammation leading to hepatocarcinogenesis. In this review, we summarize the current literature on the impact of HDV in HCC development and discuss the potential interplay between HBV, HDV and neighbouring liver tissue in liver carcinogenesis.

Novel Pegylated Interferon for the Treatment of Chronic Viral Hepatitis

Ropeginterferon alfa-2b is a novel mono-pegylated and extra-long-acting interferon, being developed for the treatment of myeloproliferative neoplasm (MPN) and chronic viral hepatitis. It has a favorable pharmacokinetic profile and less frequent dosing schedule, i.e., once every two to four weeks, compared to conventional pegylated interferon products, which have multiple isomers and are administered weekly. It was approved for the long-term treatment of polycythemia vera, an MPN, and has been included in the NCCN clinical practice guidelines for this indication. Ropeginterferon alfa-2b has demonstrated efficacy and showed a favorable safety profile for the treatment of chronic viral hepatitis in several clinical studies. In this article, we review its pharmacokinetics and available clinical data and suggest that ropeginterferon alfa-2b administered once every two weeks can serve as a new treatment option for patients with chronic viral hepatitis, including chronic hepatitis B, C, and D.

Ropeginterferon alfa-2b in patients with genotype 1 chronic hepatitis C: Pharmacokinetics, safety, and preliminary efficacy

Background and Aim

Ropeginterferon alfa‐2b (P1101) is a novel long‐acting mono‐PEGylated recombinant proline interferon (IFN) conjugated to a 40 kDa branched polyethylene glycol (PEG) chain at its N‐terminus, allowing every‐two‐week injection. It received European Medicines Agency and Taiwan marketing authorization for the treatment of polycythemia vera in 2019 and 2020, respectively. This phase 2 study aimed to evaluate the pharmacokinetics, safety, and preliminary efficacy of ropeginterferon alfa‐2b as compared with PEG‐IFN‐α2a in patients with chronic hepatitis C virus genotype 1 infection.

Methods

One hundred six treatment naive patients were enrolled in this phase 2 study and randomized to four treatment groups: subcutaneous weekly PEG‐IFN‐α2a 180 μg (group 1), weekly ropeginterferon alfa‐2b 180 μg (group 2), weekly ropeginterferon alfa‐2b 270 μg (group 3), or biweekly ropeginterferon alfa‐2b 450 μg (group 4) plus ribavirin for 48 weeks.

Results

After multiple weekly administration, serum exposure (AUC_0‐τ) in ropeginterferon alfa‐2b 180 μg was approximately 41% greater and the accumulation ratio of 2‐fold greater than PEG‐IFN‐α2a 180 μg. The incidences of flu‐like symptoms were 66.7% (18/27), 53.3% (16/30), 55.0% (11/20), and 48.3% (14/29), anxiety were 14.8% (4/27), 6.7% (2/30), 0%, and 0%, and depression were 25.9% (7/27), 13.3% (4/30), 0%, and 3.4% (1/29), for groups 1–4, respectively. Two grade 2 of 3 depression were noted in PEG‐IFN‐α2a arm, but none in ropeginterferon arms. The SVR24 rates were 77.8% (21/27), 66.7% (20/30), 80% (16/20), and 69% (20/29), respectively.

Conclusions

Ropeginterferon alfa‐2b showed longer effective half‐life and superior safety profile than PEG‐IFN‐α2a. Biweekly injection of ropeginterferon alfa‐2b will be studied in larger viral hepatitis patient population.