Estimating the Impact of Expanding Treatment Coverage and Allocation Strategies for Chronic Hepatitis C in a Direct Antiviral Agent Era

Abstract

Hepatitis C virus (HCV) infection is an important worldwide public health problem, and most of the global HCV burden is in low- to middle-income countries. This study aimed to estimate the future burden of chronic hepatitis C (CHC) and the impact of public health policies using novel antiviral agents in Thailand. A mathematical model of CHC transmission dynamics was constructed to examine the disease burden over the next 20 years using different treatment strategies. We compared and evaluated the current treatment (PEGylated interferon and ribavirin) with new treatments using novel direct-acting antiviral agents among various treatment policies. Thailand’s CHC prevalence was estimated to decrease 1.09%–0.19% in 2015–2035. Expanding treatment coverage (i.e., a five-fold increment in treatment accessibility) was estimated to decrease cumulative deaths (33,007 deaths avoided, 25.5% reduction) from CHC-related decompensated cirrhosis and hepatocellular carcinoma (HCC). The yearly incidence of HCC-associated HCV was estimated to decrease from 2,305 to 1,877 cases yearly with expanding treatment coverage. A generalized treatment scenario (i.e., an equal proportional distribution of available treatment to individuals at all disease stages according to the number of cases at each stage) was predicted to further reduce death from HCC (9,170 deaths avoided, 11.3% reduction) and the annual incidence of HCC (i.e., a further decrease from 1,877 to 1,168 cases yearly, 37.7% reduction), but cumulative deaths were predicted to increase (by 3,626 deaths, 3.7% increase). Based on the extensive coverage scenario and the generalized treatment scenario, we estimated near-zero death from decompensated cirrhosis in 2031. In conclusion, CHC-related morbidity and mortality in Thailand are estimated to decrease dramatically over the next 20 years. Treatment coverage and allocation strategies are important factors that affect the future burden of CHC in resource-limited countries like Thailand.

Direct‐acting antiviral treatment for hepatitis C virus infection and risk of incident liver cancer: a retrospective cohort study

“…Previous studies have observed that attainment of SVR by either interferon‐based or DAA‐based treatment reduces the risk of liver cancer . Due to the high SVR rates obtained with DAA therapy, many in the medical community have anticipated that the benefits of eradicating HCV without interferon would include a reduction in extra‐hepatic complications of HCV as well as the development of liver cancer among HCV‐infected populations . In contrast, some researchers have hypothesised that HCV eradication by DAA therapy could result in changes in immune surveillance and dysregulation of the anti‐tumour response, leading to an increased risk of liver cancer incidence or recurrence following DAA therapy …”

“…Based on the evidence of a reduced risk of HCC following SVR with interferon‐based therapy, it has been postulated that the uptake of direct‐acting antiviral (DAA) therapy, with its associated high SVR rates and ability to treat populations at the highest risk of HCC, will lead to reductions in HCC incidence among HCV‐infected populations . In contrast, some recent studies have reported unexpected high incidence and recurrence rates of HCC following treatment with DAA therapy, while other studies have found no increased rates or risk of HCC incidence or recurrence following DAA treatment.…”

Liver disease burden and required treatment expenditures for hepatitis C virus (HCV) infection in Thailand: Implications for HCV elimination in the new therapeutic era, a population-based study

“…Since the implementation of HCV screening in 1992, the seroprevalence in the general population has decreased to 0.9% [ 6 ]. However, rates of complicated liver diseases and CHC-related death are expected to increase in the coming decades due to the progression of diseases [ 16 ]. The lack of information on disease burden is an obstacle to establishing effective policies for prevention, screening and HCV elimination on a national scale [ 17 ].…”

“…These populations have a risk of rapid progression to severe disease, including HCC. Fortunately, current treatment allocation in Thailand prioritizes advanced liver disease stages [ 16 ]. We found that 78–83% of HCV patients (covered CHC patients with liver fibrosis stages F2–F4) in this study met the NHSO criteria and were eligible for HCV treatment via the UC program.…”

“…It is expected that liver disease complications will increase by three- to four-fold under the current treatment scenario, even in countries with a very low viremic prevalence (0.2–0.5% among adults) [ 24 ]. Although effective IFN-free DAA treatment can improve the therapeutic response (>90% with SVR), the cumulative death due to CHC depends on the treatment coverage and allocation strategies [ 16 ]. In Norway, increasing the coverage of DAA treatment to 50% is speculated to be able to reduce the incidence of cirrhosis by half [ 22 ], while, in Iran, doubling or stepwise increase in the current coverage is expected to reduce the number of deaths by >60% by 2030 [ 23 ].…”