F8 and hemophilia A: It is well established that FVIII levels directly correlate with clinical efficacy.2 Indeed, hemophilia A patients are classified into different severity levels depending on the percentage of normal hFVIII; mild (5–40% of normal, 0.05–0.40 IU/mL), moderate (1–5% of normal, 0.01–0.05 IU/mL), and severe (<1%, 0.01 IU/mL).