Noninvasive delivery of therapeutic peptides and proteins using cell-penetrating peptides

Abstract

Oral absorption of therapeutic peptides and proteins is significantly limited because of their poor permeability through the intestinal mucosal epithelium and instability in intestine and circulation. Therefore, we have currently attempted to develop the oral dosing form of these macromolecular drugs using cell-penetrating peptides (CPPs), which have strong ability to bring other molecules into numerous cells. Here, we reviewed the current researches using CPPs as drug delivery carrier, and also referred to our studies examining the usefulness of CPPs on the improvement of intestinal peptides and proteins absorption. In addition, we showed the applicability of CPPs to their nasal administration and the mechanisms associated with the absorption enhancing effect of CPPs. CPPs will be promising tool to realize the sufficient absorption of therapeutic peptides and proteins via noninvasive delivery routes.