Expression of hFVIII expression in F8^−/− mice. (A-D) Kinetics of hFVIII expression shown as activity (hFVIII:C; mean ± SD) and antigen (hFVIII:Ag; mean ± SD) levels in male F8^−/− mice following a single tail vein administration of low (2 × 10¹² vg/kg) and high dose (2 × 10¹³ vg/kg) of (A) rAAV-HLP-codop-BDD-hFVIII (BDD), (B) rAAV-HLP-codop-hFVIII-N6 (N6), or (C) rAAV-HLP-codop-hFVIII-V3 (V3). Standards consisted of normal human pool plasma (NHP) diluted in murine plasma. (D) Transgene copy number in the liver at 8 weeks following gene transfer of rAAV-HLP-codop-BDD-hFVIII, rAAV-HLP-codop-hFVIII-N6, and rAAV-HLP-codop-hFVIII-V3. (E) Blood loss in F8^−/− mice following gene transfer with rAAV-HLP-codop-BDD-hFVIII, rAAV-HLP-codop-hFVIII-N6, and rAAV-HLP-codop-hFVIII-V3 (V3) compared with that in F8^−/− mice treated with vehicle alone or recombinant FVIII.