Abstract
As the medical utility of injectable therapeutic peptides is expanding, so is the challenge of developing technologies that allow the administration of such molecules via alternative routes, considering that chronic patients requiring treatment with parenteral formulations are less adherent and compliant to the therapeutic regimens. Hence, substantial efforts have been made to develop technologies that allow the oral formulation of peptides. Due to their importance in the field of pharmaceutical technology, we describe the latest advancements made in the development of oral salmon calcitonin and oral semaglutide, in co-formulation with absorption enhancers such as 8-[(5-chloro-2-hydroxybenzoyl) amino] octanoic acid (or 5-CNAC) and N-[8-(2-hydroxybenzoyl) amino] caprylate (or SNAC). Oral semaglutide is considered to be a landmark for oral peptide delivery technology, as it is one of the very few successful examples of peptides that can be administered orally. Unlike semaglutide, oral calcitonin is still not approved by the regulatory authorities because it failed to demonstrate the anticipated effects in phase III clinical trials conducted so far. However, the efforts for obtaining an oral form of calcitonin have significantly contributed to the development of technologies that facilitate the absorption of peptide-structure macromolecules.