Model-Based Economic Analyses of Haemophilia from a Societal Perspective: A Scoping Review

Haemophilia imposes substantial lifelong humanistic and economic burdens, necessitating economic evaluations that adopt a societal perspective and comprehensively capture all relevant costs. Given the rarity of haemophilia and the limitations in data availability, modelling is crucial for integrating data from diverse sources to construct hypothetical cohorts. This review aims to identify and summarise model-based economic studies conducted in haemophilia from a societal perspective.

A systematic search was conducted across eight databases, grey literature, and manual searches up to January 5th, 2024. Eligible studies included English-language full-text publications of economic studies employing modelling techniques from a societal perspective with no date limits. The reported cost values from the included studies were adjusted to the international dollar (I$) and the United States dollar (US$) in 2022.

Out of 3340 unique records, 26 studies from 20 countries met the inclusion criteria. Among these, 17 (65.4%) were full economic evaluations, while the remaining nine (34.6%) comprised partial economic evaluations and cost analyses. Most studies (n = 20) focused on haemophilia A, with or without inhibitors. Nine studies compared prophylactic to episodic treatment. Reporting of model characteristics was frequently incomplete. Specifically, 17.6% (n = 3) and 35.3% (n = 6) of the 17 full economic evaluation studies did not report the number of health states and the cycle length, respectively. Additionally, among all studies, four (15.4%) did not perform sensitivity analysis. Key input parameters were also underreported by relevant studies, including the dose, frequency, and consumption of haemostatic therapies (19/24), unit cost of the haemostatic therapy (16/24), average body weight of the study population (10/25), the number and unit cost of days off (14/26), and the methodology for estimating indirect costs (10/26). All studies reported direct medical costs; however, only 46% reported direct formal non-medical costs, 15% reported direct informal non-medical costs, and one study included intangible costs. Indirect costs were reported in all studies. The results generally supported the cost-effectiveness or dominance of prophylaxis over episodic treatment, emicizumab over recombinant activated factor VII (rFVIIa), and gene therapy over factor VIII (FVIII) prophylaxis and emicizumab.

There were notable gaps, including inadequate reporting of model characteristics and input parameters, along with omission and mislabelling of cost categories. The findings underscore the urgent need for a disease-specific, standardised framework for societal cost categories and globally accessible costing datasets to enhance the consistency and transparency of economic studies in haemophilia.