Liposomal Delivery of Peptides and Proteins

Abstract

Controlled delivery of peptide and protein drugs constitutes a major challenge. As these compounds are generally not therapeutically active after oral administration, the parenteral route is the preferred route for their administration. However, when administered parenterally, they often show a very short circulation and biological half-life necessitating repeated injections. Further medical application and commercialization of these agents requires development of viable delivery systems to improve their therapeutic behavior (1–3). In this contribution examples of liposomal delivery approaches for peptides and proteins will be briefly described. These examples include the parenteral delivery of vasopressin, interleukin-2, tissue plasminogen activator, diphtheria toxin, and prodrug activating enzymes, and the oral delivery of antigens.