Currently, hemophilia A patients are managed with prophylactic or on-demand replacement therapy with recombinant FVIII or alternative therapeutics. The major challenges of current treatment regimens, such as the short half-life of hemophilia therapeutics with the need for frequent IV injections, encourage the current efforts for gene transfer therapy. This study will evaluate the safety and preliminary efficacy of ASC618, an AAV vector encoding B-domain deleted codon-optimized human factor VIII under a synthetic liver-directed promoter