Patient no. 5 aPTT, one-stage FIX results and mean thrombin generation AUC. (Top) There is good correlation between the drop in aPTT and the rise in FIX in the day-1 6-hours and the day-2 pretreatment samples, however the changes are not sustained, and both the aPTT and FIX essentially return to baseline by the day-2 1-hour sample. The greatest mean thrombin generation (bottom) also correlates with the peak FIX and drop in the aPTT seen in the day-2 pretreatment sample. Error bars indicate SEM.