HBV and HDV: New Treatments on the Horizon

Prevalence and characteristics of hepatitis delta virus infection in patients with hepatitis B in the United States: An analysis of the All-Payer Claims Database

BACKGROUND AND AIMS

HDV leads to the most severe form of viral hepatitis; however, the prevalence of HDV is not well understood. Using real-world data from the All-Payer Claims Database, this study estimates the prevalence of HBV/HDV infection among the chronic HBV population and describes patient/clinical characteristics for adults with HBV/HDV infection in the United States.

APPROACH AND RESULTS

Adults (≥18 years) with ≥1 inpatient claim or ≥2 outpatient claims for HDV infection or HBV in the All-Payer Claims Database from January 1, 2014, to December 31, 2020, were identified. HDV prevalence was calculated as the proportion of patients with HBV/HDV infection among total patients with HBV infection. Patient characteristics, socioeconomic status, advanced liver complications (eg, cirrhosis, HCC), and comorbidities were assessed. A total of 6719 patients were diagnosed with HBV/HDV among 144,975 with HBV and 12 months of continuous data, for a prevalence of 4.6%. At diagnosis, 31.7% of patients with HBV/HDV had advanced liver complications, including compensated cirrhosis (16.3%) and decompensated cirrhosis (10.4%). Diabetes (50.5%), hypertension (49.8%), and HIV infection (30.9%) were the top 3 comorbidities.

CONCLUSIONS

In a large database capturing approximately 80% of the US-insured population, HBV/HDV infection prevalence was 4.6% among adults infected with HBV. Patients infected with HDV had high rates of baseline liver complications and other comorbidities at the time of diagnosis, suggesting potentially delayed diagnosis and/or treatment. Earlier identification of HBV/HDV infection among the population with HBV may provide opportunities to improve linkage to care and treatment, thereby reducing the risk of liver-related morbidity and mortality.

Association of hepatitis delta virus with liver morbidity and mortality: A systematic literature review and meta-analysis

BACKGROUND AND AIMS

Studies have suggested that patients with chronic hepatitis B, either co- or superinfected, have more aggressive liver disease progression than those with the HDV. This systematic literature review and meta-analysis examined whether HDV RNA status is associated with increased risk of advanced liver disease events in patients who are HBsAg and HDV antibody positive.

APPROACH AND RESULTS

A total of 12 publications were included. Relative rates of progression to advanced liver disease event for HDV RNA+/detectable versus HDV RNA-/undetectable were extracted for analysis. Reported OR and HRs with 95% CI were pooled using the Hartung-Knapp-Sidik-Jonkman method for random-effects models. The presence of HDV RNA+ was associated with an increased risk of any advanced liver disease event [random effect (95% CI): risk ratio: 1.48 (0.93, 2.33); HR: 2.62 (1.55, 4.44)]. When compared to the patients with HDV RNA- status, HDV RNA+ was associated with a significantly higher risk of progressing to compensated cirrhosis [risk ratio: 1.74 (1.24, 2.45)] decompensated cirrhosis [HR: 3.82 (1.60, 9.10)], HCC [HR: 2.97 (1.87, 4.70)], liver transplantation [HR: 7.07 (1.61, 30.99)], and liver-related mortality [HR: 3.78 (2.18, 6.56)].

CONCLUSIONS

The patients with HDV RNA+ status have a significantly greater risk of liver disease progression than the patients who are HDV RNA-. These findings highlight the need for improved HDV screening and linkage to treatment to reduce the risk of liver-related morbidity and mortality.

Emerging Therapies for Chronic Hepatitis B and the Potential for a Functional Cure

Worldwide, an estimated 296 million people are living with chronic hepatitis B virus (HBV) infection, with a significant risk of morbidity and mortality. Current therapy with pegylated interferon (Peg-IFN) and indefinite or finite therapy with nucleoside/nucleotide analogues (Nucs) are effective in HBV suppression, hepatitis resolution, and prevention of disease progression. However, few achieve hepatitis B surface antigen (HBsAg) loss (functional cure), and relapse often occurs after the end of therapy (EOT) because these agents have no direct effect on durable template: covalently closed circular DNA (cccDNA) and integrated HBV DNA. Hepatitis B surface antigen loss rate increases slightly by adding or switching to Peg-IFN in Nuc-treated patients and this loss rate greatly increases up to 39% in 5 years with finite Nuc therapy with currently available Nuc(s). For this, great effort has been made to develop novel direct-acting antivirals (DAAs) and immunomodulators. Among the DAAs, entry inhibitors and capsid assembly modulators have little effect on reducing HBsAg levels; small interfering RNA, antisense oligonucleotides, and nucleic acid polymers in combination with Peg-IFN and Nuc may reduce HBsAg levels significantly, even a rate of HBsAg loss sustained for > 24 weeks after EOT up to 40%. Novel immunomodulators, including T-cell receptor agonists, check-point inhibitors, therapeutic vaccines, and monoclonal antibodies may restore HBV-specific T-cell response but not sustained HBsAg loss. The safety issues and the durability of HBsAg loss warrant further investigation. Combining agents of different classes has the potential to enhance HBsAg loss. Compounds directly targeting cccDNA would be more effective but are still in the early stage of development. More effort is required to achieve this goal.

Special Issue "New Therapies of Liver Diseases"

Medical and surgical treatments aimed at curing severe liver diseases and prolonging the survival of patients have improved dramatically in recent years [...].