The Forgotten Virus, Hepatitis D: A Review of Epidemiology, Diagnosis, and Current Treatment Strategies.

Hepatitis D virus (HDV) is an RNA subvirus that infects patients with co-existing hepatitis B virus (HBV) infections. HDV burden is estimated to be approximately 15-20 million people worldwide. Despite HDV severity, screening for HDV remains inadequate. HDV screening would benefit from a revamped approach that automatically reflexes testing when individuals are diagnosed with HBV if HBsAg-positive, to total anti-HDV, and then to quantitative HDV-RNA polymerase chain reaction (PCR) rather than only testing those at high risk sequentially. There are no current treatments in the United States that are Food and Drug Administration (FDA)-approved for the treatment of HDV; however, bulevirtide (BLV) is approved in the European Union conditionally and is under review with the United States FDA. Current treatment strategies in many countries are centered on the use of pegylated-interferon-alfa-2a (PEG-IFNa-2a). There are other therapies in development globally that have shown promise, including BLV, pegylated-interferon-lambda (PEG-IFN-lambda), and lonafarnib (LNF). LNF has shown substantial response in the LOWR trials. BLV is a well-tolerated drug, but it is not finite therapy and has shown significant on-treatment responses in the MYR clinical trials, and the FDA cited concerns with the manufacturing and patient preparation of the drug that have delayed approval. The PDUFA date for BLV in the United States is mid-2024. Current studies with both BLV and LNF are limited in providing sustained virological response (SVR); future trials will need to demonstrate more substantial SVR with possible triple combination trials as options.

Primary biliary cholangitis drug evaluation and regulatory approval: Where do we go from here?

Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease. The management landscape was transformed 20 years ago with the advent of Ursodeoxycholic Acid (UDCA). Up to 40% of patients do not, however, respond adequately to UDCA and therefore still remain at risk of disease progression to cirrhosis. The introduction of Obeticholic acid (OCA) as second-line therapy for patients failing UDCA has improved outcomes for PBC patients. There remains, however, a need for better treatments for higher risk patients. The greatest threat facing our efforts to improve treatment in PBC is, paradoxically, the regulatory approval model providing conditional marketing authorisation for new drugs based on biochemical markers on the condition that long-term, randomized placebo-controlled outcomes trials are performed to confirm efficacy. As demonstrated by the COBALT confirmatory study with OCA, it is difficult to retain patients in the required follow-on confirmatory placebo-controlled PBC outcomes trials when a licensed drug is commercially available. New PBC therapies in development such as the PPAR agonists, face even greater challenges in demonstrating outcomes benefit through randomized placebo-controlled studies once following conditional marketing authorisation, as there will be even more treatment options available. A recently published EMA Reflection Paper provides some guidance on the regulatory pathway to full approval but fails to recognise the importance of Real-World Data in providing evidence of outcomes benefit in rare diseases. Here we explore the impact of the EMA reflection paper on PBC therapy and offer pragmatic solutions for generating evidence of long-term outcomes through Real World data collection.

Experience and impact of stigma in people with chronic hepatitis B: a qualitative study in Asia, Europe, and the United States.

BACKGROUND: People with chronic hepatitis B (CHB) commonly experience social and self-stigma. This study sought to understand the impacts of CHB-related stigma and a functional cure on stigma. METHODS: Adults with CHB with a wide range of age and education were recruited from 5 countries and participated in 90-minute qualitative, semi-structured interviews to explore concepts related to CHB-associated stigma and its impact. Participants answered open-ended concept-elicitation questions regarding their experience of social and self-stigma, and the potential impact of reduced CHB-related stigma. RESULTS: Sixty-three participants aged 25 to 71 years (15 from the United States and 12 each from China, Germany, Italy, and Japan) reported emotional, lifestyle, and social impacts of living with CHB, including prejudice, marginalization, and negative relationship and work experiences. Self-stigma led to low self-esteem, concealment of CHB status, and social withdrawal. Most participants stated a functional cure for hepatitis B would reduce self-stigma. CONCLUSIONS: CHB-related social and self-stigma are widely prevalent and affect many aspects of life. A functional cure for hepatitis B may reduce social and self-stigma and substantially improve the health-related quality of life of people with CHB. Incorporating stigma into guidelines along with infectivity considerations may broaden the patient groups who should receive treatment.

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.

Test All for Hepatitis B Virus: Link to Care and Treatment if Quantitative DNA Positive, Vaccinate if Susceptible.

Hepatitis B infection affects approximately 262 million people worldwide and is responsible for 900,000 deaths annually. This article reviews the major factors limiting HBV elimination, which includes limited linkage to care and complicated HBV testing and treatment guidelines. The article then provides solutions to these pressing issues.

On-treatment risks of cirrhosis and hepatocellular carcinoma among a large cohort of predominantly non-Asian patients with non-cirrhotic chronic hepatitis B.

Background & Aims: The vast majority of studies evaluating differences in on-treatment risks of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB) have been conducted in Asia. Data on the course of CHB on antiviral therapy among predominantly non-Asian populations is less well described. We aimed to evaluate overall risks of cirrhosis and HCC and the influence of baseline factors on this risk among a predominantly non-Asian cohort of patients with CHB in the US. Methods: Using longitudinal data from the national Veterans Affairs database, we evaluated the incidence of cirrhosis or HCC among adults with non-cirrhotic CHB on continuous antiviral therapy. Cumulative incidence functions and adjusted Cox proportional hazards models employed competing risks methods and evaluated overall risk and predictors of developing cirrhosis or HCC while on treatment. Results: Among 2,496 patients with non-cirrhotic CHB (39.1% African American, 38.4% non-Hispanic White, 18.8% Asian, mean age 58.0 ± 13.4 years), the overall incidences of cirrhosis and HCC were 3.99 per 100 person-years (95% CI 3.66-4.35) and 0.43 per 100 person-years (95% CI 0.33-0.54), respectively. The highest incidences of cirrhosis and HCC were observed in non-Hispanic White patients (5.74 and 0.52 per 100 person-years, respectively), which were significantly higher than in Asian patients (1.93 and 0.17 per 100 person-years, respectively, p <0.0001). On multivariate regression, only baseline FIB-4 score was consistently associated with long-term risk of cirrhosis or HCC. Conclusions: Using a longitudinal cohort of predominantly non-Asian Veterans with non-cirrhotic CHB on antiviral therapy (an understudied population), we provide important epidemiological data to describe long-term risks of cirrhosis and HCC. Impact and implications: In one of the largest studies to date of a predominantly non-Asian cohort of patients with non-cirrhotic chronic hepatitis B, we provide important epidemiological data describing the long-term risks of cirrhosis and hepatocellular carcinoma among patients on antiviral therapies. Among this understudied population, the overall incidence of cirrhosis was 3.99 per 100-person-years (95% CI 3.66-4.35) and of HCC was 0.43 per 100-person-years (95% CI 0.33-0.54). These data also emphasize the importance of continued monitoring and HCC surveillance among CHB patients who are maintained on antiviral therapies.

Advancing research, awareness, screening, and linkage to care to eliminate HDV in the U.S.

HDV, which coinfects individuals living with HBV, is the most aggressive form of viral hepatitis. Compared with hepatitis B monoinfection, hepatitis delta is associated with more rapid progression to cirrhosis and an increased risk of liver cancer and death. Despite being a major contributor to hepatitis B-associated liver disease, hepatitis delta remains largely unknown to the general public, health care providers, and at-risk communities. Given the widespread lack of awareness and underdiagnosis of hepatitis delta in the US, the American Liver Foundation (ALF) and the Hepatitis B Foundation (HBF) convened a virtual Hepatitis Delta Roundtable Meeting on April 21 and 22, 2022. The Roundtable Panel included persons living with hepatitis delta, caregivers, liver disease specialists, primary care providers, state and federal public health professionals, and community-based organizations. The Panel identified several major challenges surrounding hepatitis delta, including a lack of awareness of hepatitis delta among the public and health care providers; complex risk-based testing protocols; a lack of accurate prevalence data; limited data on linkage to care; and inadequate communications among stakeholders. Potential strategies to address these challenges include improving and expanding education for different audiences; advocating for simplified protocols for hepatitis B screening with hepatitis delta reflex testing; expanding surveillance for hepatitis delta; requiring automated reporting and national notification; improving data sharing for research; and enhancing communications around hepatitis delta. The recent CDC recommendations for universal adult screening and vaccination against hepatitis B and the anticipated availability of new therapies for hepatitis delta present a unique opportunity to focus attention on this dangerous virus. The Roundtable Panel calls for urgent action to make significant progress in addressing hepatitis delta among individuals living with hepatitis B.

Hepatitis D double reflex testing of all hepatitis B carriers in low-HBV- and high-HBV/HDV-prevalence countries.

Hepatitis D virus (HDV) infection occurs as a coinfection with hepatitis B and increases the risk of hepatocellular carcinoma, decompensated cirrhosis, and mortality compared to hepatitis B virus (HBV) monoinfection. Reliable estimates of the prevalence of HDV infection and disease burden are essential to formulate strategies to find coinfected individuals more effectively and efficiently. The global prevalence of HBV infections was estimated to be 262,240,000 in 2021. Only 1,994,000 of the HBV infections were newly diagnosed in 2021, with more than half of the new diagnoses made in China. Our initial estimates indicated a much lower prevalence of HDV antibody (anti-HDV) and HDV RNA positivity than previously reported in published studies. Accurate estimates of HDV prevalence are needed. The most effective method to generate estimates of the prevalence of anti-HDV and HDV RNA positivity and to find undiagnosed individuals at the national level is to implement double reflex testing. This requires anti-HDV testing of all hepatitis B surface antigen-positive individuals and HDV RNA testing of all anti-HDV-positive individuals. This strategy is manageable for healthcare systems since the number of newly diagnosed HBV cases is low. At the global level, a comprehensive HDV screening strategy would require only 1,994,000 HDV antibody tests and less than 89,000 HDV PCR tests. Double reflex testing is the preferred strategy in countries with a low prevalence of HBV and those with a high prevalence of both HBV and HDV. For example, in the European Union and North America only 35,000 and 22,000 cases, respectively, will require anti-HDV testing annually.

Chronic Hepatitis B Virus and Hepatitis D Virus: New Developments.

Hepatitis B virus (HBV) and hepatitis D virus are leading causes of morbidity and mortality worldwide. Despite the availability of HBV vaccinations that are 98% to 100% effective, an estimated 820,000 annual deaths were attributed to HBV in 2019, mainly related to the sequelae of cirrhosis and hepatocellular carcinoma. Because disease prevalence is concentrated outside of the United States, it is overlooked, but with expanded vaccination recommendations provided by the Centers for Disease Control and Prevention and recommended screening, as well as heightened awareness by health care providers, we can work toward the eradication of this preventable disease.

Establishing baseline framework for hepatitis B virus micro-elimination in Ho Chi Minh City, Vietnam - A community-based seroprevalence study.

Background: We conducted a community-based seroprevalence study using three HBV seromarkers (HBsAg, anti-HBs, anti-HBc) in Ho Chi Minh City (HCMC), Vietnam, to (1) determine the prevalence of HBV serologic profiles; (2) document factors associated with HBV infection or susceptibility; and (3) propose strategies toward HBV elimination by 2030. Methods: During 2019-2020, we deployed a multistage cluster design with probability proportionate to size, to recruit 20,000 adults for an HBV screening and linkage to care program citywide. Screening results with interpretation, recommendations, and health education materials were returned to participants. Post-study surveys were conducted within three months to identify gaps in linkage to care. Findings: Of the 17,600 adults invited, 15,275 (86.7%) participated in the study, 14,674 (96.1%) completing all data for final analyses. The prevalence of HBsAg (+) and HBV-naïve were 7.5% and 37.7%, respectively. HBV vaccination rates were 18.7% and about 50% of HCMC population had been exposed to HBV. Of the persons with HBsAg (+), 27.1% linked to care (76% used health insurance). There were wide variations in HBsAg (+) and HBV vaccination rates between districts, risk factors, and socio-economic statuses. Interpretation: The significant disease burden of and gaps in the continuum of care highlight the need and urgency to address the HBV public health problem in Vietnam. Using three screening seromarkers that tailor interventions to the needs of HBV micro-populations could be an effective strategy to pursue HBV elimination goals. Funding: Gilead Sciences Inc; Roche Diagnostic International Ltd; Roche Diagnostics-Vietnam; Abbott Diagnostics-Vietnam; Hepatitis B Foundation; Medic MedicalCenter, Vietnam; Center of Excellence for Liver Disease in Vietnam, Johns Hopkins University School of Medicine.

Simplifying Treatment Criteria in Chronic Hepatitis B: Reducing Barriers to Elimination.

BACKGROUND: Early, sustained hepatitis B virus (HBV) DNA suppression reduces long-term risks of hepatocellular carcinoma. Chronic hepatitis B (CHB) treatment criteria are complex. Simplifying criteria will improve timely linkage to therapy. We evaluated treatment eligibility patterns among US patients with CHB and propose stepwise simplification of CHB treatment criteria. METHODS: Using 2016-2020 Quest Diagnostics data, we evaluated treatment eligibility among patients with CHB (2 positive HBV tests [HBV surface antigen, HBV e antigen, or HBV DNA] ≥6 months apart) using American Association for the Study of Liver Disease (AASLD), European Association for Study of the Liver (EASL), Asian Pacific Association for Study of the Liver (APASL), and Asian American Treatment Algorithm (AATA) criteria. RESULTS: Among 84 916 patients with CHB, 6.7%, 6.2%, 5.8%, and 16.4% met AASLD, EASL, APASL, and AATA criteria, respectively. Among treatment-ineligible patients with CHB, proportion with significant fibrosis (aspartate aminotransferase platelet ratio index >0.5) were 10.4%, 10.4%, 10.8%, and 7.7% based on AASLD, EASL, APASL, and AATA, respectively. In the proposed treatment simplification, the proportion of patients with CHB eligible for therapy increased from 10.3% for step 1 (HBV DNA >20 000 IU/mL, elevated alanine aminotransferase [ALT] level) to 14.1% for step 2 (HBV >2000 IU/mL, elevated ALT level), 33.5% for step 3 (HBV DNA >2000 IU/mL, any ALT level), and 87.2% for step 4 (detectable HBV DNA, any ALT level). CONCLUSIONS: A large proportion of patients with CHB not meeting established treatment criteria have significant fibrosis. Simplifying criteria to treat all patients with detectable HBV DNA will reduce complexity and heterogeneity in assessing treatment eligibility, improving treatment rates and progress toward HBV elimination.

The importance of triple panel testing for hepatitis B and the burden of isolated anti-hepatitis B core antibodies within a community sample.

Within the United States (US), 2.4 million individuals are living with chronic hepatitis B, but less than 20% are diagnosed. Isolated anti-hepatitis B core (iAHBc) antibodies indicate serology in an individual that is positive for anti-HBc antibodies, while negative for surface antigen (HBsAg) and surface antibodies (anti-HBs). A result of iAHBc could indicate a chronic occult bloodstream infection, necessitating further testing. This study assesses the prevalence and risk factors associated with anti-HBc and iAHBc within community high-risk screening in Greater Philadelphia. Participants (n = 177) were screened for HBsAg, anti-HBs, and anti-HBc during community screening events in 2022. Chi-square tables and Firth logistic regression were used to describe the data and to assess the odds of iAHBc. The findings indicate that there was an iAHBc prevalence of 7.3% (n = 13) within our study. The odds of anti-HBc were increased for immigrants from the Western Pacific (4.5%) and Africa (11.9%). Individuals born in Africa had 7.93 greater odds for iAHBc than those born in the Americas, and these odds are multiplied by 1.01 for every 1-year increase in age. Our data show a high burden of iAHBc within high-risk and often hard-to-reach communities. Triple panel screening should be incorporated into all HBV screening programs, in accordance with current Centers for Disease Control and Prevention (CDC) universal screening recommendations, to ensure a comprehensive picture of the disease burden and reduce the risk of missing people with occult hepatitis B and those at risk for viral reactivation or liver complications.

Active site polymerase inhibitor nucleotides (ASPINs): Potential agents for chronic HBV cure regimens.

Chronic hepatitis B virus (HBV) infection affects 240 to 300 million people worldwide. In the nucleus of infected hepatocytes, the HBV genome is converted to covalently closed circular DNA (cccDNA), which persists and serves as a transcriptional template for viral progeny. Therefore, a long-term cure for chronic HBV infection will require elimination of cccDNA. Although currently available nucleos(t)ide analogues (eg, tenofovir disoproxil fumarate, tenofovir alafenamide, entecavir) effectively control HBV replication, they are seldom curative (functional cure rate ∼10%) and require lifelong treatment for most patients. As such, antiviral agents with novel mechanisms of action are needed. Active site polymerase inhibitor nucleotides (ASPINs) noncompetitively distort the HBV polymerase active site to completely inhibit all polymerase functions, unlike traditional chain-terminating nucleos(t)ide analogues, which only target select polymerase functions and are consumed in the process. Clevudine, a first-generation ASPIN, demonstrated potent and prolonged HBV suppression in phase 2 and 3 clinical studies, but long-term treatment was associated with reversible myopathy in a small number of patients. ATI-2173, a novel next-generation ASPIN, is structurally similar to clevudine but targets the liver and demonstrates potent anti-HBV activity on and off treatment, and may ultimately demonstrate an improved pharmacokinetic and safety profile by significantly reducing systemic clevudine exposure. Thus, ATI-2173 is currently in clinical development as an agent for HBV cure. Here, we review the mechanism of action and preclinical and clinical profiles of clevudine and ATI-2173 to support the role of ASPINs as part of curative regimens for chronic HBV infection.

Low Performance of Hepatitis Delta Virus Testing Among 2 National Cohorts of Chronic Hepatitis B Patients in the United States.

INTRODUCTION: The purpose of this study was to evaluate hepatitis delta virus (HDV) testing patterns among US adults with chronic hepatitis B (CHB). METHODS: HDV testing was evaluated among CHB patients using Quest Diagnostics (2016-2020) and Veterans Affairs (2010-2020) data. RESULTS: Among 157,333 CHB patients (Quest), 6.7% received HDV testing, among which 2.2% were positive. HDV testing was higher in male patients, younger individuals, and patients with advanced liver disease. Among 12,002 CHB patients (Veterans Affairs), 19.7% received HDV testing, among which 3.1% were positive. HDV testing was higher in younger individuals and Asians. DISCUSSION: Low HDV testing was observed among 2 large US cohorts of adults with CHB.