Structural model
A novel rFIX-Fc population PK model using clinical data including
children <12 years of age was developed (Table 2). A
two-compartment model with a central and a peripheral compartment
adequately described our data. Addition of a second peripheral
compartment did not improve the fit of the model to the data. All PK
parameters were allometrically scaled. With allometric scaling, body
weight is included in the structural model. IIV could be estimated for
CL, V1 and V2, with a correlation between CL and V1. The clinical data
supported the estimation of IOV on CL.