10 - Oral Delivery of Proteins and Peptides: Concepts and Applications

Abstract

Publisher Summary This chapter discusses in detail the factors affecting protein and peptide absorption, barriers to protein absorption, penetration pathways, and various approaches to improve the oral delivery of proteins and peptides. The chapter also elaborates the methods to study oral absorption and various strategies in oral immunization. Therapeutic peptides and proteins can be successfully delivered through the oral route. The para- and trans-cellular routes of absorption and proteolytic enzyme activity that may potentially degrade therapeutic peptides are described. Oral delivery of therapeutic peptides and proteins is only successfully attained if the peptides and proteins bypass the various penetration or enzymatic barriers at each stage. The goal is to increase typical bioavailability from less than 1% to at least 10% to 20%. Methods to increase drug flux without associated toxicity seek to minimize proteolytic degradation and chemical modification. This chapter explains in detail the anatomy and physiology of oral mucosa. The chapter also explains the parts of the oral cavity including the epithelium, basement membrane, and connective tissues. The chapter discusses in detail the transport mechanism in the gastrointestinal tract, as well as strategic use of the oral route for immunization.