OBJECTIVES: To assess the cost-effectiveness of diagnostic testing for hepatitis delta virus (HDV), consisting of the enzyme-linked immunosorbent assay (ELISA) test with a confirmatory HDV ribonucleic acid (RNA) test compared to no testing in patients with hepatitis B virus (HBV) in the United Kingdom (UK).

METHODS: A cost-effectiveness model was developed following a targeted literature search, leveraging a combination of a decision tree and Markov model approach. The decision tree covered the initial testing component for HDV in an HBV positive (HBV+) population, while the Markov model covered the HDV treatment component. In the Markov model, patients could receive treatment with pegylated interferon (off-label use) or bulevirtide. The model had a lifetime horizon with a baseline mean patient age of 36 years, while costs and outcomes were discounted at 3.5%.

RESULTS: The base case incremental cost-effectiveness ratio (ICER) comparing diagnostic testing for HDV against no testing was £26,984. While the model predicted higher incremental total costs (£10,525) for the intervention, which were mainly driven by drug treatment costs, the results showed that an additional 0.39 quality-adjusted life years were generated per patient. The model predicted the number of tests needed to avoid clinical events, such as progression to decompensated cirrhosis (45), progression to hepatocellular carcinoma (54) or liver transplants (406). Fibrosis health state utility had the largest impact on deterministic sensitivity analysis results, with the ICER ranging between £21,166-£37,212. Furthermore, probabilistic sensitivity analysis was conducted to test the impact of parameter uncertainty. At a willingness to pay of £30,000, testing for HDV in the UK was cost-effective with a probability of 75.5%.

CONCLUSIONS: Screening all HBV+ patients in the UK using the ELISA test with a confirmatory HDV RNA test is cost-effective and would reduce the number of liver transplants, thus reducing the HDV burden in the UK.