IntroductionThe standard of care for people with haemophilia A (PwHA) is regular prophylactic therapy with Factor VIII. However, very little is known about the treatment preferences of PwHA with and without inhibitors, or their caregivers, when presented with the choice between intravenous and subcutaneous prophylactic treatments with different modes of action, side effect risk and frequency of administration.MethodsWe conducted a discrete choice experiment to assess the preferences of PwHA or their caregivers. The survey was conducted in Australia, New Zealand, Canada, France, Italy and the United Kingdom.ResultsThere were 56 respondents. The majority of PwHA had hereditary HA (78%) rather than spontaneous HA (22%). Most PwHA were diagnosed when they were under 12 months old (65%). The model identified two segments based on treatment preferences. There is heterogeneity between PwHA in their treatment preferences. People with and without inhibitors prefer to receive treatment via a subcutaneous injection compared to an intravenous infusion. However, for PwHA, efficacy is key; they value a reduction in the annual bleed rate. For those without inhibitors, this also includes a reduction in the risk of developing inhibitors. The side effect risk, administration risk and storage requirements were prioritised differently in each segment.ConclusionsResults from this study may inform decisions about the value of existing and new treatments for PwHA.