Comparison of the mouse-monkey chimeric anti-primate FVIII neutralizing antibody cyVIII-2236 with the original mouse antibody VIII-2236 in an APTT assay. (A) Effects of cyVIII-2236 and VIII-2236 on APTT in normal cynomolgus monkey plasma. (B) Influence of 300 µg/mL cyVIII-2236 and VIII-2236 on APTT-shortening activity of ACE910 in FVIII-deficient human plasma. Data are expressed as means ± SD (n = 3). The bars depicting SD are shorter than the height of the symbols. The symbols for the group without anti-FVIII antibody are hidden behind the symbols for the other groups in panel B.