Figure 2.

Illustration of between‐drug extrapolation of pediatric covariate functions to scale hepatic plasma clearance (CLp) from adults to pediatric patients for drugs eliminated by the same isoenzyme. The black dot in both graphs shows the adult hepatic CLp value for the model drug (“true” adult CLp_M) and the test drug (“true” adult CLp_T). The solid black line represents the change in CLp of the model drug throughout the pediatric age range, which is described by a pediatric covariate function based, in this example, on bodyweight (CLp ontogeny_M (bodyweight)). The dashed black line represents the scaled pediatric CLp predicted for the test drug by between‐drug extrapolation of the pediatric covariate function obtained for the model drug (CLp ontogeny_M (bodyweight)).