Biomembrane permeability of peptides: strategies to improve their mucosal uptake

In order to gain a therapeutic response after mucosal administration peptide drugs have to permeate the absorption membrane based on the mucus layer (I) and the epithelial tissue (II) in significant quantities. The peptide drug transport across the membrane can be improved by the use of mucolytic agents and the permeation enhancers. The generation of novel, more potent permeation enhancers, based on an improved knowledge of the absorption membrane in combination with the appropriate delivery systems will strongly improve the bioavailability of mucosally applied peptide drugs.