1536
Belle et al.
planned to determine an optimal study size and design for
complete EK analyses. If a larger data set is necessary, then
the population method may not be practical. The advantages
of the population approach is that it requires roughly half the
number of incubations (140–150 incubations) as the tradi-
tional analyses, but provides additional information such as
EK parameter estimates for each liver examined and inter-
liver variability for the parameter.
In conclusion, similar EK parameters for POD were ob-
tained with both the traditional and population approach.
Both approaches identified CYP1A2 as the low KM1 CYP
responsible for POD. Traditional studies indicated that
CYP2C19 is the enzyme responsible for the high KM2 com-
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