1. Clarifications regarding the surgery indication, such as definitions of the surgery types, safety data required prior to surgery, and evaluation times of the surgery outcome data during the study, were given as requested by the regulatory agencies 2. The regulatory agencies recommended studying two different dosing regimens to arrive at the optimal dose of BAY81-8973. Consistent with this recommendation, the study design was revised from prophylaxis (20-40 IU/kg BAY81-8973 administered 2-3 times/week) versus on-demand treatment to prophylaxis using 2 different dosing regimens (BAY81-8973 high-dose [30-40 IU 3 times/week] or low-dose [20-30 IU 2 times/week]) versus on-demand treatment 3. Addition of a secondary objective of demonstration of non-inferiority of BAY81-8973 dose determined by CS/EP versus BAY81-8973 dose determined by CS/ADJ as measured by the proportion of bleeds controlled by 1 or 2 infusions (among all bleeds) in subjects treated on-demand

1. The definition of severe hemophilia A in the inclusion criteria was clarified and expanded to allow subjects with previous medical history documentation of < 1% FVIII:C, determined by one-stage clotting assay, included in the trial without further testing/confirmation of severe hemophilia A, if the screening result turned out to be equal to or higher than 1%. The rationale for the change was to allow subjects with previously documented severe hemophilia A enrolled into the trial without the delay of having another one-stage clotting assay performed, since severity is not known to change during the course of the disease. The documented historical evidence of severe hemophilia A could be either from a previous Bayer hemophilia clinical trial, or from a previously performed one-stage clotting assay from a certified laboratory 2. The number of surgeries was increased from ≥10 to ≥15, and the classification of surgery types was clarified to enable a more thorough evaluation of the safety and efficacy of BAY 81-8973 in the surgical setting. The amendment further specified that ≥8 surgeries were major surgical procedures 3. To further ensure subject safety, the requirement was added that BAY 81-8973 was not to be supplied for use in the surgical setting until its hemostatic activity had been assessed in at least 20 bleeding events 4. To be consistent with the sister protocol (Study 12954; EudraCT Number: 2009-012149-43), the following exclusion criterion was added: “Any subject who cannot forego at least 3 days without receiving FVIII for washout purposes.” 5. The dosage range for prophylaxis treatment was clarified as occurring in 5 IU/kg increments over the range of 20-40 IU/kg 2-3 times per week (ie, low dose: 20, 25, or 30 IU/kg, administered 2 times per week; high dose 30, 35, or 40 IU/kg administered 3 times per week)

1. For safety reasons, subjects with known hypersensitivity to mouse protein were excluded from participation in the study 2. Primary and secondary study objectives were revised and rearranged to include objectives for results of this study alone, and addendum objectives were added for the pooled results of this study and Study 12954