Budget impact analysis of newly available treatments for chronic hepatitis C infection in Hong Kong

Abstract

Background Hepatitis C is a global public health issue causing 3-4 million new infections each year. Revolutionary change of treatment landscape is underway with approval of second generation direct-acting antivirals (DAAs) which possess remarkable safety, efficacy and tolerability. In Hong Kong, Sofosbuvir (SOF), Ledipasvir/Sofosbuvir (LED/SOF) and Ombitasvir/Paritaprevir/ Ritonavir plus Dasabuvir (VP) are registered; SOF and VP are listed as special drugs in Hospital Authority (HA) Drug Formulary. However, local pharmacoeconomic study is yet to be established to evaluate the cost impact of new DAAs. Objective The goal of this study is to evaluate the budget impact of SOF, LED/SOF and VP treatments to the Hong Kong healthcare system from the HA perspective, as well as the benefits of adding LED/SOF to the formulary. Method Prevalence and incidence of genotype 1 hepatitis C infection in Hong Kong were estimated using local and overseas data. Budget impact analysis was conducted under best scenario – treating all prevalent patients in the first year and incident patients in subsequent years. 5-year time horizon was adopted. Individual treatment cost was compared with standard of care (Boceprevir, BOC treatment) and between new DAAs; total expenditure and clinical management costs incurred with and without introduction of new DAAs were also compared. Results Prevalent population was estimated to be 12,674 in 2016 and incident population was 304 per year in 2017-2020. Comparing with BOC treatment, new DAA treatments present cost-saving manner in treatment cost per SVR (sustained virologic response) of individual treatment, clinical management costs, total cost (5,571 vs. 5,540 million) and total cost per SVR (8,892 vs. 6,004 million) over the 5 years. Over 90% of total expenditure occurred in the first year under the best scenario. Sensitivity analysis assessed cost variance due to variation in cost ratio, market share of drugs, proportion of treatment experienced and SVR of drugs. VP would be the most “budget friendly” DAA, followed by LED/SOF as both DAAs would cause additional reduction in total cost per SVR when increase in market share. Conclusion Lower treatment cost per SVR and total costs suggested cost-saving from introduction of new DAAs to the formulary. Moreover, listing LED/SOF to the formulary would be beneficial to total cost per SVR and clinical management costs, and provide patients of other genotype infection with equitable access of optimal treatment. Further studies on other HCV genotypes, recently approved DAAs and cost impact from reduced risk of liver complications are required in order to assess the overall budget impact of newly available hepatitis C treatments.