The particle drifting effect (PDE) has gained significant attention as a mechanism for enhancing oral drug absorption. This Webinar will cover the fundamental concept of PDE, along with clinical, in vivo, and in vitro data supporting its role.
For most poorly soluble drugs, oral absorption is typically limited by solubility and unstirred water layer (UWL) permeability (SL-U), rather than the dissolution rate. However, when the dose strength is increased or particle size is reduced, preclinical in vivo and clinical studies often show higher drug absorption levels—sometimes exceeding the maximum absorbable dose.
Since the saturated (equilibrium) solubility remains unchanged by dose strength or particle size (unless reduced to below 100 nm), the observed increase in absorption suggests enhanced UWL permeation. When drug particles drift into the UWL, the flux across this layer increases, facilitating greater absorption.
About the speaker
Kiyohiko (Kiyo) Sugano is a professor at Ritsumeikan University with over 20 years of experience in the pharmaceutical industry in Japan and the UK, having worked at Chugai, Pfizer, and Asahi Kasei Pharma.
He earned his Bachelor's and Master’s degrees in Chemistry from Waseda University and a Ph.D. in Pharmaceutical Sciences from Toho University. His research focuses on drug oral bioavailability, studying the molecular-level physicochemical interactions between drugs and components of the gastrointestinal tract.