Are Published Health Economic Models for Chronic Hepatitis B Appropriately Capturing the Benefits of HBsAg Loss? A Systematic Literature Review

Predictors of therapeutic response to peginterferon α‑2a and nucleos(t)ide analog combination therapy for HBeAg‑negative chronic hepatitis B: 1‑year follow‑up after treatment

Chronic hepatitis B (CHB) is a major global health concern. Guidelines for the management of hepatitis B virus (HBV) indicate that the loss of hepatitis B surface antigen (HBsAg) is a key endpoint of interest. The present study aimed to examine long-term changes in HBsAg levels in HBV-DNA-negative, hepatitis B e-antigen (HBeAg)-negative patients treated with peginterferon (Peg-IFN) α-2a and nucleos(t)ide analog (NA), and to examine the conditions that make them susceptible to HBsAg decline. A total of 17 patients with CHB treated with NA and Peg-IFN were observed for 96 weeks (48 weeks of Peg-IFN therapy and 48 weeks of post-treatment follow-up). In this study, responders were defined as those with a 50% or greater decrease in HBsAg levels from baseline at week 96. Beginning at week 16 of Peg-IFN therapy, there was a significant difference in the decrease in HBsAg levels from baseline between the responders and non-responders. In responders, HBsAg levels tended to be >60% lower 16 weeks after Peg-IFN initiation than before initiation. Age at the start of NA use and the duration of NA use before Peg-IFN treatment initiation were significant pretreatment factors associated with HBsAg response. In conclusion, Peg-IFN was revealed to be more effective in HBeAg-negative patients with CHB who started NA at a young age and have been on long-term treatment, particularly if the HBsAg levels decreased to less than 60% of the starting level at week 16 after starting Peg-IFN treatment.

Cost-effectiveness of combination antiviral treatment with extended duration for hepatitis B e antigen (HBeAg)-negative chronic hepatitis B in China

Background

Hepatitis B surface antigen clearance or seroconversion is rarely achieved for patients using nucleoside analogs or pegylated interferon alpha monotherapy approaches. Several recent studies have confirmed the benefit of a combination of these two approaches for selected chronic hepatitis B patients. However, few reports have investigated long-term outcomes or health economic evaluation for hepatitis B surface antigen clearance. The aim of this study was to perform a cost-effectiveness analysis of the long-term use of this combination strategy among selected hepatitis B e antigen-negative patients.

Methods

Drawing on experience in China, we used a Markov model to simulate disease progression among a population of hepatitis B e antigen-negative chronic hepatitis B patients with surface antigen levels of ≤1,000 IU/mL through a discrete series of health states. We compared nucleoside analog monotherapy to the combination strategy over a prolonged period. We measured lifetime costs, quality-adjusted life-years and incremental cost-effectiveness ratios.

Results

The combination therapy produced 15.8 quality-adjusted life-years, and cost US dollars (USD) 45,032 per patient. The monotherapy gave 13.9 quality-adjusted life-years, and had a cost of USD 52,064. The incremental cost-effectiveness ratio of the monotherapy (USD −3,755 per quality-adjusted life-year) did not obtain extended dominance over combination therapy. The most cost-effective option was combination therapy among patients with hepatitis B surface antigen levels of ≤10 IU/mL, which had the lowest calculated cost of USD 35,318 and most quality-adjusted life-years (16.7).

Conclusions

A long-term combination treatment strategy for selected hepatitis B e antigen-negative chronic hepatitis B patients may prolong quality-adjusted life-years compared with nucleoside analog monotherapy. Chronic hepatitis B patients with a hepatitis B surface antigen level of ≤10 IU/mL were the most cost-effective population under this strategy.

Systematic Literature Review and Critical Appraisal of Health Economic Models Used in Cost-Effectiveness Analyses in Non-Alcoholic Steatohepatitis: Potential for Improvements

BACKGROUND

Non-alcoholic steatohepatitis (NASH) is a severe, typically progressive form of non-alcoholic fatty liver disease (NAFLD). The global prevalence of NASH is increasing, driven partly by the global increase in obesity and type 2 diabetes mellitus (T2DM), such that NASH is now a leading cause of cirrhosis. There is currently an unmet clinical need for efficacious and cost-effective treatments for NASH; no pharmacologic agents have an approved indication for NASH.

OBJECTIVE

Our objective was to summarise and critically appraise published health economic models of NASH, to evaluate their quality and suitability for use in the assessment of novel treatments for NASH, and to identify knowledge gaps, challenges and opportunities for future modelling.

METHODS

A systematic literature review was performed using the MEDLINE, Embase, Cochrane Library and EconLit databases to identify published health economic analyses in patients with NAFLD or NASH. Supplementary hand searches of grey literature were also performed. Articles published up to November 2019 were included in the review. Quality assessment of identified studies was also performed.

RESULTS

A total of 19 articles comprising 16 unique models including either NAFLD as a whole or NASH alone were included in the review. Structurally, most models had a state-transition component; in terms of health states, two different approaches to early disease states were used, modelling either progression through fibrosis stages or NAFLD/NASH-specific health states. Conditions that frequently co-exist with NASH, such as obesity, T2DM and cardiovascular disease were not captured in models identified here. Late-stage complications such as cirrhosis, decompensated cirrhosis and hepatocellular carcinoma were consistently included, but input data (e.g. costs, utilities and transition probabilities) for late-stage complications were frequently sourced from other liver disease areas. The quality of included studies was heterogenous, and only a small proportion of studies reported internal and external validation processes.

CONCLUSION

The health economic models identified in this review are associated with limitations primarily driven by a lack of NASH-specific data. Identified models also largely overlooked the intricate association between NASH and other conditions, including obesity and T2DM, and did not capture the increased risk of cardiovascular events associated with NASH. High-quality, transparent, validated health economic models of NASH will be required to evaluate the cost effectiveness of treatments currently in development, particularly compounds that may target other non-hepatic outcomes.