Linear plot of baseline-corrected FIX activity level after the infusion of 50 IU/kg of rIX-FP and previous FIX product (PK population). Mean FIX activity levels of 50 IU/kg rIX-FP, 50 IU/kg rFIX, and 50 IU/kg pdFIX were measured in international units per decaliter. Vertical bars represent SD. A horizontal dotted line represents the 5-IU/dL FIX activity level.