Economic Burden of Haemophilia from a Societal Perspective: A Scoping Review.

Introduction: Haemophilia is a rare genetic bleeding disorder that leads to musculoskeletal complications. The high cost of haemophilia treatment necessitates a thorough evaluation of its economic burden. However, due to the difficulty of estimating direct non-medical, indirect, and intangible costs, studies often underestimate the actual economic burden of haemophilia. This scoping review aims to summarise economic studies in haemophilia conducted from a societal perspective.

Methods: A systematic search across eight scholarly databases, grey literature, and reference lists until the 5^th of July 2023 was conducted to identify relevant studies. The inclusion criteria encompassed full-text, English-language publications of economic analyses in congenital haemophilia from a societal perspective. Model-based studies and those adopting a payer perspective were excluded. Costs were adjusted to international dollars (I$) and US dollars (US$) in 2022 for comparability.

Results: Out of 2993 potential sources identified, 25 studies met the inclusion criteria, covering 7226 persons with haemophilia across 22 countries. All studies reported direct medical costs, with four excluding the cost of haemostatic therapy. Fifteen studies reported direct formal non-medical costs, while eight reported direct informal non-medical costs. All but one study reported the indirect costs. The average annual costs of haemophilia varied widely based on treatment modality, disease severity, geographical location, and included cost categories. When including the cost of clotting factor replacement therapy (CFRT), the total cost for severe haemophilia without inhibitors ranged from 1566 I$ to 700,070 I$ per person per year (lowest value reported in India and highest in the United States). CFRT represented up to 99.9% of the total cost for those receiving prophylaxis and up to 95.1% for episodic treatment. Haemostatic therapies accounted for 82% of the total cost in patients with inhibitors.

Conclusion: There is a significant heterogeneity in defining cost categories required for a comprehensive economic analysis from a societal perspective. While haemostatic therapies constitute a substantial portion of the overall cost, direct non-medical and indirect costs are crucial as they are often paid out-of-pocket and may impede access to treatment. It is essential for haematologists and economists to establish a standardised costing framework for future studies, particularly in the era of novel therapies.