What is the Simulation Module?
Unlike predictive the ADMET models described in other modules, the Simulation Module features a special set of predictive models that are not statistical in the sense of simply turning molecular structures into direct property estimations. In the Simulation Module the results are simulated using selected ADMET predictions, dose and predefined human physiology, and solving a deterministic, region-dependent system of differential equations.
This system is based on the “Human-Physiological-Fasted” version of the ACAT model of drug absorption employed in its entirety by our software GastroPlus™ reflecting compounds’ dissolution, permeation, transit and regional dependence along the intestinal tract. Users are advised to consult the GastroPlus documentation for further details inherent in the ACAT model. The module predicts human intestinal absorption (HIA) for 1, 10, 100, 1000 mg dose. It can also predict the oral dose to achieve a specific plasma concentration. This module is currently available in ADMET Predictor 7.2 (it has not been ported to ADMET Predictor 8). However, we anticipate that it will be available in the version after ADMET Predictor 8.
Robert Fraczkiewicz, Michael B. Bolger, Walter S. Woltosz
What are the so-called “nonlinearities” in pharmacokinetics (PK) for multiple dosage of oral drugs? What are their causes and implications? While developing the Simulation Module  – an in silico tool for conducting PK simulations based on the Advanced Compartmental Absorption and Transit (ACAT™) model  – we have discovered a handful of interesting cases of nonlinear PK behavior.