Factor VIII activity (left axis) and inhibitor titer (right axis) during hospital stay, 10 years after diagnosis: note logarithmic scale on y-axes. Shaded blue area represents the reference range for factor VIII activity; shaded orange area represents the reference range for the Bethesda assay. *Denotes the time when the patient received susoctocog alfa. anti-hFVIII, anti-human factor VIII; anti-rpFVIII, anti–recombinant porcine factor VIII; CSA, chromogenic substrate assay; FVIII, factor VIII; Pred, prednisolone.