Cost-effectiveness analysis of oral anti-viral drugs used for treatment of chronic hepatitis B in Turkey

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

OBJECTIVES

Sustained hepatitis B surface antigen (HBsAg) loss or 'functional cure' (FC) is considered an optimal treatment endpoint by international clinical guidelines for chronic hepatitis B (CHB), yet rarely is this achieved with current standard of care (SoC). This leads to an under-reporting of FC in clinical trials, observational studies and health economic (HE) models. This paper systematically identifies and assesses how FC is incorporated in published HE models of CHB.

METHODS

A systematic literature review was conducted in PubMed and Embase (conducted February 2019) to review how HBsAg loss is captured in HE models. The following items were extracted: rate of (and transition probabilities to) HBsAg loss, HBsAg loss health state costs, and HBsAg loss health state utilities.

RESULTS

Sixty-five economics evaluations were identified, and < 50% of these (27/65) incorporated HBsAg loss in their models. Only 15/27 stated HBsAg loss health state costs, 15/27 stated HBsAg loss health state utilities, and 11/27 mentioned treatment-specific transition probabilities to HBsAg loss. The majority of sources these inputs were derived from are not transparent.

CONCLUSIONS

The benefits of FC in current HE models are not well captured, as FC is often not reported or not directly related to modelled treatments. This has the potential for novel agents with higher efficacy compared with SoC to be overlooked and undervalued if their worth is not appropriately communicated. In order to ensure optimal access for patients to new and effective therapies, it is important that the benefits of FC are better assessed and captured within HE models.

A descriptive study of racial inequalities in mortality from hepatocellular cancer before and after licensure of lifesaving drugs for hepatitis C virus in the United States

BACKGROUND

Since 1979, mortality from hepatocellular cancer (HCC) has doubled in the United States (US). Lifesaving drugs, prohibitively expensive for some, were approved and marketed to treat hepatitis C virus (HCV), a major risk factor for HCC, beginning in 1997. After the prior introduction of other lifesaving innovations, including active retroviral drug therapy for human immunodeficiency virus and surfactant for respiratory distress syndrome of the newborn, racial inequalities in their mortalities increased in the US. In this descriptive study, we explored racial inequalities in mortality from HCC before and after licensure of HCV drugs in the US.

METHODS

The US Centers for Disease Control and Prevention Wide-ranging ONline Data for Epidemiologic Research (WONDER) were used to describe HCC mortality rates from 1979 to 2016 in those 55 years of age and older, because they suffer the largest disease burden. Joinpoint regression was used to analyze trends. To estimate excess deaths, we applied White age-sex-specific rates to corresponding Black populations.

FINDINGS

From 1979 to 1998, racial inequalities in mortality from HCC in the US were declining but from 1998 to 2016 racial inequalities steadily increased. From 1998 to 2016, of the 16,770 deaths from HCC among Blacks, the excess relative to Whites increased from 27.8% to 45.4%, and the trends were more prominent in men. Concurrently, racial inequalities in mortality decreased for major risk factors for HCC, including alcohol, obesity and diabetes.

INTERPRETATION

These descriptive data, useful to formulate but not test hypotheses, demonstrate decreasing racial inequalities in mortality from HCC which were followed by increases after introduction of lifesaving drugs for HCV in the US. Among many plausible hypotheses generated are social side effects, including unequal accessibility, acceptability and/or utilization. Analytic epidemiological studies designed a priori to do so are necessary to test these and other hypotheses.

Cost-Effectiveness of Tenofovir Alafenamide for Treatment of Chronic Hepatitis B in Canada

BACKGROUND/AIM

Tenofovir alafenamide (TAF) has been approved for treating chronic hepatitis B (CHB) due to a proposed better safety profile in comparison with current therapies. We evaluated the cost effectiveness of TAF and other available treatment options for hepatitis B envelope antigen (HBeAg)-positive and HBeAg-negative CHB patients from a Canadian provincial Ministry of Health perspective.

METHODS

A state-transition model based on the published literature was developed to compare treatment strategies involving entecavir (ETV), tenofovir disoproxil fumarate (TDF), and TAF. It adopted a lifetime time horizon. Outcomes measured were predicted number of liver-related deaths, costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs).

RESULTS

For HBeAg-positive patients, TAF followed by ETV generated an additional 0.16 QALYs/person at an additional cost of Can$14,836.18 with an ICER of Can$94,142.71/QALY compared with TDF followed by ETV. Of the iterations, 28.7% showed that it is the optimal strategy with a Can$50,000 willingness-to-pay threshold. For HBeAg-negative patients, ETV followed by TAF would prevent an additional 13 liver-related deaths per 1000 CHB patients compared with TDF, followed by ETV. It generated an additional 0.13 QALYs/person at an additional cost of Can$59,776.53 with an ICER of Can$461,162.21/QALY compared with TDF, followed by ETV. TAF-containing strategies are unlikely to be a rational choice in either case. The results were sensitive to the HBeAg seroconversion rates and viral suppression rates of the treatments.

CONCLUSIONS

Our analysis suggests that TAF is not cost effective at its current cost. A 33.4% reduction in price would be required to make it cost effective for HBeAg-positive patients with a Can$50,000 willingness-to-pay threshold.