Estimated mean FIX activity profiles adjusted to a dose of 50 U/kg. rFIX indicates the FIX activity profile for patients' previous recombinant FIX product and pdFIX indicates the FIX activity profile for patients' previous plasma-derived FIX product, both measured in international units per milliliter. N9-GP indicates the FIX activity profile for N9-GP measured in units per milliliter. Vertical bars indicate the SEM.