OBJECTIVES: To estimate the reduction in societal economic burden among patients with severe hemophilia A without inhibitors currently managed with prophylaxis in the US after the introduction of valoctocogene roxaparvovec.

METHODS: An economic model was developed to estimate the change in burden of a cohort of adult males with severe hemophilia A managed with prophylaxis after the introduction of valoctocogene roxaparvovec over a 10-year horizon. As the valoctocogene roxaparvovec launch price is unknown, a placeholder of $2.9M/typical patient was used and 4% of patients were assumed to return to prophylaxis annually. Direct medical costs (FVIII concentrate or emicizumab, other non-FVIII medical costs) and non-medical costs (early retirement, caregiver, underemployment, absenteeism, transfer payments) were considered. Total economic burden and distribution among payers were estimated. Sensitivity analyses were conducted.

RESULTS: After the introduction of valoctocogene roxaparvovec, there is an expected 30% reduction in total economic burden over 10 years among patients treated with valoctocogene roxaparvovec, from $5.5M/patient managed with prophylaxis to $3.9M/patient treated with valoctocogene roxaparvovec. The cumulative 10-year reduction in economic burden is $564M (public: $230M; private: $334M; household: $422K), representing a 3% reduction among the modelled cohort. Assuming 4% of treated patients resume prophylaxis annually, post-gene therapy prophylaxis cost is $513M over 10 years. Cost-savings occurs after 4 years. Nationally, 99% of the burden reduction is attributable to savings in direct medical costs. Non-medical costs are the main driver of economic burden in households, accounting for 78% of total costs borne by households. There is a 17% reduction in household-borne non-medical costs among patients treated with valoctocogene roxaparvovec, driven by decreased absenteeism.

CONCLUSIONS: While the initial, one-time cost of valoctocogene roxaparvovec is significant, its use will reduce the overall societal economic burden of severe hemophilia A that would otherwise be managed with prophylaxis and result in cost-savings after 4 years.