OBJECTIVES: Hereditary angioedema (HAE) is a rare genetic disease caused by the deficiency or dysfunction of C1 esterase inhibitor (C1-INH), and characterized by recurring episodes of severe swelling, commonly affecting the skin, gastrointestinal tract, or upper airway (which can be life-threatening). Frequency and severity of attacks vary. Replacement C1-INH therapies provide effective relief; however, there is a lack of comparative data on economic outcomes.

METHODS: Acquisition costs for human plasma-derived and recombinant C1-INH were collected from public databases for the UK, Netherlands, Czech Republic, and Bulgaria. Attack rates and the mean number of doses required to control each attack were collected from published studies; data from randomized controlled studies were analysed separately from real-world and open-label studies. Cost per attack was estimated considering the distribution of patient weights and labelled dose regimens.

RESULTS: The proportion of patients requiring multiple doses to control an attack ranged from 9.1% to 63.8% in randomized studies and 0.2% to 30.9% in real-world studies. In general, recombinant C1-INH was less expensive than plasma-derived options, due to lower re-dosing rates. In the analysis using randomized studies, average savings per patient per attack (and per year) were £712 (£19,151) in the UK, €264 (€7,095) in the Netherlands, €469 (€12,610) in Czech Republic, and €312 (€8,391) in Bulgaria. In the analysis using real-world studies, average savings per patient per attack (and per year) were £447 (£12,036) in the UK, €61 (€1,640) in the Netherlands, €288 (€7,735) in Czech Republic, and €166 (€4,454) in Bulgaria.

CONCLUSIONS: Based on published studies and drug prices, treatment with recombinant C1-INH may provide savings when compared with plasma-derived products and require fewer repeat doses to control an HAE attack. In addition to the economic impact of re-dosing, future analyses should consider the humanistic impact of rapid control of attacks.