Evaluating codon-optimized and hyperfunctional FIX transgenes by IDLV delivery in hemophilic mice. Mice were intravenously administered with the indicated doses (in transducing units), and clotting activity was measured by chromogenic FIX activity assays (A-C) on plasma samples collected at the indicated times after IDLV administration. (A) A total of 109 TU (n = 3) of ET.cFIX.142T IDLV or ET.co-cFIX.142T IDLV. (B) A total of 109 TU (n = 4) of ET.co-cFIX.142T IDLV or in a separate experiment 109 TU (n = 4) of ET.co-cFIXR388L.142T IDLV or 4 × 109 TU (n = 1) of ET.co-cFIXR338L.142T IDLV. (C) D-dimer levels (black bars) were determined by ELISA, and FIX activity (white bars) was analyzed by chromogenic assay in mice injected with different vector doses as indicated compared with noninjected control. The D-dimer positive control is shown. Data are mean ± SEM. *P < .05 (t test or ANOVA). **P < .01 (t test or ANOVA). ***P < .001 (t test or ANOVA).
