Peptides are biomaterials composed of 2–50 amino acids present in the body. Peptides are easier to manufacture and more cost-effective than antibodies in terms of production cost. In addition, peptide drugs have higher target specificity and lower toxicity than small molecules. In particular, peptides bind to the exact location where the two proteins interact, thereby providing excellent protein-protein interaction (PPI) inhibitory efficacy.

Desmopressin

Interacting proteins

The major obstacle in the development of peptide drugs is the improvement in the cell membrane permeability and metabolic stability of peptides. For this Purpose, technologies for cell-penetrating peptides (CPPs) and modification of peptide structures have been developed. Especially, technologies to synthesize cyclic peptides and staple peptides contribute to the improvement of metabolic stabilities and activities of peptides.

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  Peptides

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  Cyclic peptides

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  Stapled peptides

To develop peptides for use as oral drugs, various carrier formulations using nanomaterials have been introduced. Recently, phase 3 trials have been completed for oral formulations of peptides, such as semaglutide, octreotide, and salmon calcitonin. Oral semaglutide is currently a market leader, since it was approved by the FDA in 2019.