Are Oral Peptide Drugs on the Horizon?
Peptides and proteins generally have low bioavailability when taken by mouth, and this hurdle has generally prevented the oral delivery of many biologic drugs in the past. However, plant cell walls may be ideal transporters to move protein-based drugs through the digestive system without the drugs being exposed to degradation by stomach acids and enzymes, say a group of researchers from the University of Pennsylvania. In a new study, the researchers, led by Henry Daniell, PhD, professor and interim chair, Department of Biochemistry, say that drugs manufactured in plant cells are not only delivered orally more efficiently, they also allow for the elimination of various purification and cold chain steps that are typically required with proteins manufactured in mammalian, yeast, and bacterial cells.
Using plant systems as bioreactors has many benefits, the researchers write. “Protein drugs [PDs] made in chloroplasts are stable in lyophilized plant cells when stored at ambient temperatures, maintaining their folding and functional efficacy for several years, thereby eliminating expensive cold chain. In addition, the freeze-drying process increases the concentration of PDs and eliminates bacterial contamination.” Importantly, they write, because plants are not hosts for human pathogens, there is low risk for the transmission of immunogenic components.
Source: BioPharm International