Physiologically Based Pharmacokinetics (PBPK)

Physiologically based pharmacokinetics (PBPK) describes the pharmacokinetics (PK) of a drug by integrating its physicochemical and in vitro ADME properties (drug specific) with physiological parameters (system specific) of the body. This is known as the ”bottom up” approach (mechanistic), the opposite of empirical description of PK (sum of exponentials/compartments) known as “top down” approach. The mechanistic basis of PBPK enables prediction of PK profiles in humans and preclinical species. PBPK modelling and simulation has become an integral part of drug development (Model Informed Drug Development –MIDD)– e.g. prediction of first time in human dose, drug-drug interactions, doses in different populations. PBPK modelling is being used for decision making by regulatory agencies – e.g. waiver of clinical trials, labelling information, optimal design of clinical trials.