The Need for Speed-Kinetic Limits of Drug Transporters

We recently published an analysis in Trends in Pharmacological Sciences, assessing the impact of transporters on cellular drug permeability based on quantitative data for drug transport kinetics and transporter expression levels [1,2]. Our aim was to explore what properties transporters would need to have if – as hypothesized in a series of publications over the past few years – drug diffusion across the lipid parts of cell membranes is negligible, and transporter-mediated processes explain all experimental observations of cellular drug flux.