This is a first-in-humans gene therapy study for subjects diagnosed with severe hemophilia A. A one time infusion of the gene therapy product (BAX888) will be given with the hope of eliminating or reducing the need for prophylactic and/or on-demand use of FVIII concentrate therapy. Up to 10 subjects will be enrolled study-wide with up to two subjects enrolled at MUSC. This study will require weekly visits to the study clinic after initial infusion for the first 15 weeks followed by monthly visits for the first year. Compensation will be provided.