Peptides that can be taken as a pill

Structure of a double-bridged peptide that is not degraded by enzymes in the stomach and intestines. The two stabilizing chemical bridges are shown in red. Credit: C. Heinis (EPFL) - Peptides represent a billion-dollar market in the pharmaceutical industry, but they can generally only be taken as injections to avoid degradation by stomach enzymes. Scientists at EPFL have now developed a method to generate peptides that resist enzymatic degradation and can be taken orally. Peptides are short chains of amino acids that occur in our body, in plants or bacteria to control diverse functions. Several peptides are used as drugs such as insulin, which controls the metabolism of sugar, and cyclosporine, which suppresses organ rejection after transplants. More than 40 peptides are already approved as drugs, generating revenues in the billions.