PBPK modeling is a useful tool for predicting physiological parameters that directly affect drug PK, using mathematical models to simulate blood flow through systemic organs. PBPK modeling can provide pharmacokinetic (PK) parameters that guide drug discovery, drug dose selection, and aid in drug-drug interaction risk assessment. BOC Sciences provides PBPK modeling service to explore pharmacology to accelerate drug development programs, providing our clients with reliable results that support the decision-making process.
The physiologically-based pharmacokinetics (PBPK) modeling is based on the knowledge of physiology, biochemistry and anatomy, which simulates the blood flow in the circulatory system of the body and interconnects the tissues or organs of the body, and follows the mass balance principle for the metabolism of drugs in the body. The concept of PBPK model was introduced by Theorell in 1937. In the PBPK modeling, each tissue of the body is represented by its own compartment.
Unlike the traditional compartmental model, which treats all metabolic and excretory organs as central or peripheral compartments, each organ or tissue in the PBPK model is viewed as a separate partition. For this reason, the PBPK model is able to calculate the total metabolite population, and those metabolites that do not enter the systemic circulation due to being rapidly excreted or metabolized. The model not only distinguishes between different transporters in tissues, but also describes the process of their transport, whether passive diffusion or activetransport.
The PBPK model is divided into three main components: drug (experimental or predicted ADME data), system (physiological data related to the ADME properties of the drug), and trial (information on the trial design, such as administration route).
Fig. 1 A whole-body PBPK model.
The scope of application of the PBPK modeling includes environmental, drug toxicity and risk assessment, pharmacokinetics and new drug development. The assessment of hazards to humans in toxic environments was the main area of application in the early stages of PBPK modeling development. In recent years, the application of PBPK modeling in pharmacokinetic studies and new drug development has gradually increased. PBPK modeling is flexible and can provide information on drug metabolism, target organ, protein binding, etc., which, combined with the results of pharmacodynamic studies, can help analyze the mechanism of drug action. In addition, it has shown its advantages and characteristics in population pharmacokinetic (popPK) studies, drug-drug interaction (DDI) studies, and PK-PD studies.
The PopPK approach uses mathematical models to characterize PK data and draw conclusions about the variability of drug concentrations in a population of patients receiving clinically relevant doses of a target drug.
PBPK modeling is an assessment tool for complex interaction studies involving multiple drugs and genetic polymorphism. PBPK has the potential to predict DDI by integrating intrinsic and extrinsic factors such as genetic polymorphisms of CYP/transport proteins or environmental cues.
BOC Sciences offers superior PBPK modeling services to support all stages of drug development projects. We connect with global clients in the pharmaceutical industry, using tools such as PBPK modeling to help drug developers understand the effects of drugs on the body, help with drug discovery or clinical development decisions, and inform regulatory communications.