Researchers at the University of Washington have discovered how to create peptide molecules that can slip through membranes to enter cells

This new ability to design membrane-permeable peptides with high structural accuracy opens the door to a new class of medicines

Small-molecule drugs for example, aspirin  are small enough to slip through cell membranes to do their work

Protein therapeutics — for example, monoclonal antibodies — can target more complex ailments,

but the protein molecules are typically too big to wedge their way through lipid-based cell walls

Peptide drug can bind protein targets in the body more precisely than small-molecule drugs, promising fewer side effects

Most peptides have chemical features that cause them to cling to water molecules instead of slipping through a cell’s lipid membrane.

First, the researchers made synthetic peptides that were less likely to interact with water.

They also designed peptides that could change shapes as they moved through membranes.

Peptide-based drugs could address the challenges posed by antibiotic resistance and also offer a new strategy to fight COVID-19.