This is a single arm, phase 4, prospective, open-label, United States single-center study to
determine the hemostatic characteristics of Hemlibra (emicizumab) as measured by coagulation
laboratory parameters in the mild hemophilia A male patient population with endogenous
altered FVIII (baseline FVIII activity of >5% to 30%). The safety and hemostatic efficacy of
Hemlibra (emicizumab) in this patient population will be investigated. Secondary outcomes
will assess changes in joint health and quality of life in treated patients.