Generation of a Set of Simple, Interpretable ADMET Rules of Thumb

TLDR

The rules were derived from intuitive molecular properties—molecular weight, logP, and ionization state—that chemists can readily modify. The study identified simple, structure‑property rules linking higher molecular weight, higher logP, and ionization state to poorer ADMET outcomes, showing that lower MW and logP values improve solubility, permeability, bioavailability, and other pharmacokinetic properties, and that these rules complement predictive black‑box models.

Abstract

A set of simple, consistent structure-property guides have been determined from an analysis of a number of key ADMET assays run within GSK: solubility, permeability, bioavailability, volume of distribution, plasma protein binding, CNS penetration, brain tissue binding, P-gp efflux, hERG inhibition, and cytochrome P450 1A2/2C9/2C19/2D6/3A4 inhibition. The rules have been formulated using molecular properties that chemists intuitively know how to alter in a molecule, namely, molecular weight, logP, and ionization state. The rules supplement the more predictive black-box models available to us by clearly illustrating the key underlying trends, which are in line with reports in the literature. It is clear from the analyses reported herein that almost all ADMET parameters deteriorate with either increasing molecular weight, logP, or both, with ionization state playing either a beneficial or detrimental affect depending on the parameter in question. This study re-emphasizes the need to focus on a lower molecular weight and logP area of physicochemical property space to obtain improved ADMET parameters.