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is administered by two different modes (such as IV bolus and infusion).
If a relationship can be established between the plasma levels of a drug
administered by IV bolus and by IV infusion, super imposition can be
challenged by the use of the transformed IV infusion data.
Superimposition of this transformed high dose IV infusion data on low
58
dose IV bolus data was effected by the outlined procedure that
follows.
Analysis and transformation of IV infusion data. The post-infusion
data were fitted to a sum of either two (Study #7 and 8) or three (Study
53
#11) exponentials in accordance with the equation,
P' e Tr *t-T^ + A' e-a *t-T* + B' e- ^ *t-T) Eq. 15
where T is the time at which infusion was stopped and t is the time
after initiating the infusion. The first term in the above expression is
set equal to zero when the post-infusion data are fitted to a
2-compartment body model. The relationship between P and P' of equations
. 53
2 and 15 respectively is
P = P'T tt / (l-e-7T T ) Eq. 16
Similarly, the relationships between A, A' and B, B' are
A = A'T a/(l-e-a T ) Eq. 17
B = B'TS / (l-e~ BT ) Eq. 18
The calculated P, A, and B values were used to generate the Q? .
values of equation 2. These could be the calculated plasma
concentrations if the same dose was administered by IV bolus. These
estimated Cpca^c concentrations obtained from the infusion studies were