In vivo coagulation potential assessed by ROTEM in HA mice infused with D519V/E665V/K1813A and D519V/E665V FVIII mutants. WT-FVIII (2 μg/kg) or mutant; D519V/E665V/K1813A (0.25, 0.5, 1, and 2 μg/kg) or D519V/E665V (1 μg/kg), or phosphate-buffered saline (PBS) were infused to the HA mice. CaCl₂ was added to citrated whole-blood samples obtained from HA mice, followed by a ROTEM assay. The (A) CT and (B) α-angle parameters in WT mice and HA mice are shown. Statistical analysis between WT-FVIII (2 μg/kg) and FVIII mutants or no FVIII administration was performed using Dunnett multiple comparison test. Significant differences are defined as P < .05 (∗P < .05 and ∗∗P < .01). Each data point represents an individual mouse. The straight line in each graph represents the mean values. ns, not significant.