PK / PD Modeling

PK/PD modeling is the integration of pharmacokinetics with a response. The response may be positive (such as a biomarker being targeted or desired efficacy); or the response may be negative (such as a toxicological endpoint). PK/PD modeling allows for prediction of the desired or undesired response, based on a particular administered dose or measure of exposure.

PK / PD Modeling Overview

• Conducted using either a compartmental PK model or a PBPK model  
• Applies to both small and large molecules
• Often combined with scaling to develop a predictive PK/PD human model 

Common Uses 

• Dose regimen design 
• Interspecies scaling / Phase I exposure predictions
• Assessment of potential impacts on efficacy from PK changes (due to material lot changes) 
• Preclinical & clinical optimization study design

Regulatory Guidance & Timing

PK/PD modeling is not specifically required in regulatory guidance, but the FDA has strongly suggested including modeling in the data package. In addition, the 2017 EMA guideline for first-in-human (FIH) dosing recommends that estimation of FIH should be based on state-of-the-art modeling (e.g. PK/PD and PBPK) and or using allometric factors. A PK/PD model can be critical for predicting FIH doses of large molecules with approaches using a minimally anticipated biological effect level (MABEL) or a pharmacologically active dose (PAD).

PK / PD modeling studies typically occur during late discovery through clinical.

Related Content

• In vivo PK & pharmacology studies
• In vitro cell assays, specifically investigating pharmacology