Liver enzyme levels in hemophilia B dogs after intraportal delivery of AAV vectors. AAV2/8 LSP-cFIX-W was administrated as a single intraportal injection into the liver of 2 hemophilia B dogs at a dose of 5.25 × 10¹² GC/kg (G43, ▪; H12, ○). Hemophilia B dog D39 (•) was initially injected intraportally with AAV2 LSP-cFIX-W at a dose of 2.8 × 10¹² GC/kg, and 995 days after the first injection, the dog received a second intraportal injection with AAV2/8 LSP-cFIX-W vector at a dose of 5 × 10¹² GC/kg. Hemophilia B dog C52 (▵) received a first intraportal injection of AAV2 LSP-cFIX at a dose of 2.8 × 10¹¹ GC/kg; 1180 days after the first injection, the dog received a second intraportal injection with AAV2/5 LSP-cFIX-W vector at a dose of 2.3 × 10¹³ GC/kg. (A,C,E) Alanine aminotransferase (ALT); shaded areas represent normal range of ALT, which is 12 to 118 U/L. (B,D,F) Aspartate aminotransferase (AST); shaded areas represent normal range of AST, which is 15 to 66 U/L.