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

objectivesSustained 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.

methodsA 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.

resultsSixty-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.

conclusionsThe 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.