Cell-penetrating peptide-mediated topical delivery of biomacromolecular drugs

Biomacromolecules play an important role in the treatment of many diseases, but their topical application has been limited by their poor cell membrane permeability. Cell-penetrating peptides (CPPs) have been investigated over the past few decades as a potential strategy to overcome this challenge. CPPs can effectively mediate the cellular uptake of poorly internalized biomacromolecules without unfavorable side effects and have therefore attracted considerable interest as a viable alternative to existing parenteral therapies involving biomacromolecules. In this review, we will highlight the application of CPPs to the non-invasive delivery of biomacromolecules, with a focus on percutaneous and nasal absorption of biomacromolecules administered using CPPs.