Research Progress of Oral Peptide and Protein Drugs

Peptides and protein drugs have been widely used in clinical practice, with advantages of high specificity, safety and activity. However, these drugs still require parenteral administration, which can be a deterrent to medication compliance. There is a growing interest in oral delivery due to its high safety and good compliance, but it faces tremendous challenges of low bioavailability and short half-life, which are related to structural organization and physiological function of the gastrointestinal tract. The poor bioavailability of peptides and protein drugs has become a bottleneck in the development of oral drug delivery pathways of such drugs. However, with the development of technology, the research on the promotion of the oral absorption of peptides and protein drugs has achieved much progress in preclinical and clinical trials in recent years. This paper reviews recent advances in research on absorption pathways of peptides and protein drugs, influence factors, strategies to promote their oral absorption as well as related clinical trials.