Pharmacokinetics

Pharmacokinetics (PK) is the branch of pharmacology that explores the effects of the body on a drug. PK is used to quantitatively describe the absorption, distribution, metabolism, and excretion (ADME) of a drug. Insights into the PK of a drug not only are important for informing the drug development program but also are critical for guiding input and decision making by regulatory authorities such as the Food and Drug Administration (FDA). The two common approaches to the modeling of the PK of a drug are physiologically-based pharmacokinetics (PBPK) and compartmental pharmacokinetics. This section details the optionally licensed PBPKPlus module that Simulations Plus developed for the simulation of physiologically-based pharmacokinetics of drug candidates. It also details the use of a compartmental PK model to carry out one-, two-, or three-compartmental pharmacokinetic simulations of drug candidates.

This section covers the following topics:

• Introduction to Physiologically Based Pharmacokinetics

• Tissue Models for PBPK

• Tissue Types in a PBPK Model

• Tissue Distribution Calculations

• Kp Calculation Variable Assumptions

• Population Estimates for Age Related Physiology

• Compartmental Pharmacokinetics

For details about the internal standards that were used to define the equations in this section, see Equation Standards.