Impact of hepatitis D reflex testing on the future disease burden: A modelling analysis

Double reflex testing improves the efficacy and cost effectiveness of hepatitis delta diagnosis in southern Spain

This study aims to evaluate the prevalence of undiagnosed hepatitis delta in southern Spain (Andalusia) and assess the effectiveness and cost-efficiency of implementing reflex testing for hepatitis D detection in HBsAg-positive patients. A multicenter ambispective study was conducted in 17 Andalusian hospitals. The retrospective phase (January 2018-June 2022) analyzed diagnostic processes for hepatitis delta in HBsAg-positive patients. The prospective phase (October 2022-March 2023) implemented reflex testing, performing anti-HDV serology on all HBsAg-positive patients without prior testing. HDV RNA testing followed for those who tested anti-HDV-positive. In the retrospective phase, out of 18,583 HBsAg-positive patients, anti-HDV tests were performed on 3,436 (18%), identifying 205 (6%) positive cases. HDV RNA was tested in 158 (77%) anti-HDV-positive patients, with 69 (44%) testing positive. In the prospective phase, out of 2,384 HBsAg-positive patients without prior anti-HDV testing, 2,293 (96%) were tested, identifying 109 (4.7%) positive cases. HDV RNA was analyzed in 97 (89%) anti-HDV-positive patients, with 30 (31%) testing positive. Reflex testing increased anti-HDV detection by 77%, resulting in a fourfold increase in detecting anti-HDV-positive patients and a threefold increase in detecting HDV RNA-positive patients, reducing undiagnosed HDV RNA-positive cases to 4% compared to 45% with clinical practice. Cost analysis indicated a saving of €265,954 with reflex testing. Reflex testing improves HDV detection, reduces costs, and simplifies diagnosis, making it an efficient strategy for managing chronic hepatitis D patients.

Clinical and economic value of bulevirtide in the treatment of chronic hepatitis D

BACKGROUND/AIMS

Bulevirtide (Hepcludex®) is the first drug approved for the treatment of chronic hepatitis D (CHD), unlike the current off-label treatment (PEG-IFN-α), limited in clinical practice and associated with post-treatment relapses. In a hypothetical cohort of CHD patients in Spain, the study aim was to compare the efficiency of bulevirtide with PEG-IFN-α in terms of clinical events avoided and associated cost savings.

METHODS

A validated economic model reflecting the natural history of the disease was used to project lifetime liver complications and costs for two hypothetical cohorts treated with bulevirtide or PEG-IFN-α. The model considered progression to complications such as decompensated cirrhosis (DCC), hepatocellular carcinoma (HCC), liver transplantation (LT), and death. The efficacy rates used at 24 and 48 weeks were defined as the combined response rate for bulevirtide and undetectable HDV RNA to PEG-IFN-α. The numbers of clinic events and associated costs were evaluated from the perspective of the National Healthcare System.

RESULTS

In a hypothetical cohort of 3882 patients, bulevirtide reduced the numbers of complications events in comparison to PEG-IFN-α (152 DCC, 113 HCC, 11 LT, and 321 deaths over a lifetime). This was associated with a reduction of event-related costs of €11,837,044 (DCC €1,138,059; HCC €1,503,583; LT €7,834,291; and death €1,361,111).

CONCLUSION

In patients with CHD, bulevirtide could prevent a significant number of clinical events compared to PEG-IFN-α and contribute to cost savings through these reduction in liver complications. Further testing for hepatitis D virus is needed so that more patients can benefit from bulevirtide.

Cost analysis of hidden hepatitis D virus infection in Spain

INTRODUCTION

A significant percentage of patients coinfected with hepatitis B virus (HBV) and hepatitis D virus (HDV) are undiagnosed. Coinfected patients progress to advanced liver disease faster than HBV monoinfected patients, thereby consuming more healthcare resources. The aim was to perform an analysis to determine the cost of hidden HDV infection in Spain.

METHODS

An analytical model was developed to estimate the prevalence of hidden HDV infection with/without advanced liver disease at the time of diagnosis. An epidemiological flow chart was established to quantify undiagnosed chronic hepatitis D patients. The percentages of patients with compensated cirrhosis (CC), decompensated cirrhosis (DC), hepatocellular carcinoma (HCC) and requiring liver transplantation (LT) and their annual costs were subsequently obtained from the literature. Direct healthcare costs were considered within a time horizon of 1 year. For patients without advanced disease, the consumption of healthcare resources was obtained from an experts panel.

RESULTS

A total of 2180 patients with hidden HDV infection were estimated; of these, 1188 (54%) had advanced liver disease (29%-CC, 57%-DC, and 8%-HCC) or underwent LT (6%), and 992 (46%) patients did not have advanced disease. The total annual cost of hidden HDV would be € 17.8million (€ 16.9million with advanced disease and € 882,400 for those without).

CONCLUSIONS

Hidden HDV infection represents a high economic burden in Spain due to the rapid progression of liver disease in affected patients. These results highlight the importance of early diagnosis to prevent future clinical and economic burden related to liver disease progression.

The diagnostic cascade for patients with hepatitis delta infection in France, 2018-2022: A cross-sectional study

BACKGROUND AND AIMS

Chronic hepatitis D infection is the most severe form of viral hepatitis and can rapidly progress to cirrhosis or hepatocellular carcinoma. Despite recommendations for systematic screening of hepatitis B surface antigen (HBsAg)-positive individuals, data from real-world studies have reported a low frequency of hepatitis D (or delta) virus (HDV) screening. Our cross-sectional analysis evaluated the diagnostic cascade for hepatitis D infection in tertiary centres and described the characteristics of HDV-positive patients.

METHODS

A total of 6772 individuals who tested HBsAg positive for the first time between 2018 and 2022 were retrospectively included. Demographic, clinical and laboratory data were analysed.

RESULTS

A total of 5748 HBsAg-positive individuals (84.9%) were screened for HDV infection. The screening rate varied from 63% to 97% according to the screening strategy used in the centres including or not HDV reflex testing. The prevalence of HDV infection was 6.3%. HDV RNA levels were determined in 285 of the 364 (78.3%) HDV antibody screening-positive patients, and 167 (58.6%) had active HDV infection. 66.8% were males, with a mean age of 44.9 years. A total of 97.5% were born abroad, and 92.9% were HBeAg negative. At the time of diagnosis, HDV RNA levels were 6.0 Log UI/mL; 60.1% had alanine aminotransferase >40 U/L, and 56.3% had significant fibrosis (≥F2), including 41.6% with cirrhosis. The most common genotype was HDV-1 (75.4%). Coinfections were not uncommon: 7.4% were HIV positive, and 15.0% were HCV antibody positive.

CONCLUSIONS

The present study highlights the need for increased screening and monitoring of HDV infection. Reflex testing helps to identify HDV-infected individuals.

Advances in hepatitis delta research: emerging insights and future directions

OBJECTIVES

Hepatitis delta virus (HDV) is a defective virus needing the envelope provided by hepatitis B virus (HBV) in order to enter liver cells and propagate. Chronic HDV infection is considered the most severe viral hepatitis, resulting in accelerated fibrosis progression until cirrhosis and its complications (hepatocellular carcinoma, liver decompensation) compared with HBV mono-infected patients. Off-label treatment with interferon has represented the only treatment option in the last 40 years, resulting in suboptimal virological response rates and being limited by safety issues especially in patients with advanced cirrhosis. Recently, the first HBV-HDV entry inhibitor Bulevirtide (BLV) has been approved by the European Medicines Agency (EMA) for treatment of chronic compensated HDV.

METHODS

This review summarises most recent updates on HDV epidemiology, diagnosis and treatment, with a special focus both on clinical trials and real-life studies about BLV. An overview on new HDV compounds under development is also provided.

RESULTS

BLV, the HBV-HDV entry inhibitor, has shown promising safety and efficacy data in clinical trials and in real-life studies, also in patients with advanced cirrhosis and portal hypertension. However, according to EMA label treatment is currently intended long-term until clinical benefit and predictors of responses are still undefined. The potential combination with PegIFNα seems to increase virological and clinical responses. New compounds are under development or in pipeline for treatment of HDV.

CONCLUSION

After more than 40 years since HDV discovery, new treatment options are currently available to provide efficient strategies for chronic hepatitis Delta.

Impact of anti-HDV reflex testing at HBs antigen positive discovery in a single center France: Support for primary HDV screening in France

BACKGROUND

Hepatitis Delta virus (HDV) infection is a major cause of liver-related morbidity and mortality in patients infected with HBV, with a global HDV prevalence uncertain. In France, 2 to 5 % of HBs antigen (HBsAg) carriers present anti-HDV antibodies (anti-HDV). The EASL recommends testing for anti-HDV in all HBsAg-positive patients. Since January 2022, we have systematically carried out anti-HDV serology when a positive HBsAg is discovered (new HBsAg carriers).

OBJECTIVES

We evaluated the benefit of anti-HDV reflex testing after one year of practice by comparing anti-HDV and HBsAg serology data over the last six years, among the new HBsAg carriers and all the HBsAg carriers.

STUDY DESIGN

HBsAg and anti-HDV were screened using the Abbott Architect HBsAg quanti kit and the DIA.PRO HDVAb kit. Serological, demographic, virological, and clinical data were analyzed.

RESULTS

Implementing anti-HDV reflex testing leads to more than a 2-fold increase in diagnoses of HDV infection among all HBsAg carriers. If the anti-HDV positive rate remains stable among the new HBsAg carriers, a significant increase in the anti-HDV positive rate from 6.8 % to 10.3 % was observed considering all HBsAg carriers. Interestingly, the discovery of anti-HDV carriage increased from 3.9 % to 6.5 % in 2022, allowing earlier identification of HBV-HDV-infected patients and a fast referral to hepatologists for adequate clinical management and, in some cases, the introduction of bulevirtide-based therapy.

CONCLUSIONS

Our preliminary results at one year seem promising and evaluating the cost-effectiveness of reflex tests in real life with feedback would be helpful.

Is there a need for universal double reflex testing of HBsAg-positive individuals for hepatitis D infection?

Hepatitis D virus (HDV) can infect HBsAg-positive individuals, causing rapid fibrosis progression, early decompensation, increased hepatocellular carcinoma risk, and higher mortality than hepatitis B virus (HBV) mono-infection. Most countries lack high-quality HDV prevalence data, and the collection techniques employed often bias published data. In recent meta-analyses, HDV prevalence in HBsAg-positive patients reaches 5%-15% and is even significantly higher in endemic areas. Since HBV vaccination programs were implemented, HDV prevalence has decreased among younger populations. However, owing to immigrant influx, it has increased in some Western countries. The current practice of HDV screening in HBsAg-positive individuals is stepwise, based on physician's discretion, and limited to at-risk populations and may require numerous visits. Double reflex testing, which includes anti-HDV testing in all HBsAg-positive individuals and then HDV RNA testing for anti-HDV-positive ones, is uncommon. Reflex testing can identify more HDV infection cases and link identified patients to further care and follow-up. Moreover, laboratory-based double reflex screening is less biased than physician-led testing. Therefore, healthcare providers should learn about reflex testing, and federal and provincial hepatitis control programs should implement laboratory-based double reflex testing to obtain reliable HDV prevalence estimates. The test's cost-effectiveness depends on the number of HBV-positive patients screened to identify one HDV-positive patient. Such testing may be viable in areas with low HBsAg but high HDV prevalence. However, its economic impact on areas with low HDV prevalence needs further study.