FIX activity after injection of a single dose of rIX-FP or previous FIX product (PK population). Mean baseline-uncorrected plasma FIX activity after administration of a single infusion of 25 or 50 IU/kg of rIX-FP or 50 IU/kg previous FIX product (pdFIX or rFIX). Linear (A) and semilog (B) plots of rIX-FP over time. (C) Matched-pair plot patients who participated in both 50 IU/kg rIX-FP and 50 IU/kg previous FIX product. FIX activity was measured in international units per deciliter. Vertical bars represent SD. A horizontal dotted line represents the 5 IU/dL FIX activity level. (D) Box plot of FIX activity of rIX-FP at day 7 and day 14; the bar within the box represents the median, diamond represents the mean, the ends of the box are the IQR, and whiskers represent minimum and maximum values. FIX activity levels are not available for a dose of 25 IU/kg rIX-FP at day 14.