Peptide Hydrogels: Self-Assembling Gels That Can Deliver Drugs Slowly Over Time

This was a comprehensive narrative review of the published literature on peptide hydrogels for drug delivery. The authors examined different types of hydrogel systems, their self-assembly processes, the variety of peptide sequences used as building blocks, and the mechanisms by which drugs are released from these systems.

As biologic drugs (peptides, proteins, antibodies) increasingly dominate the pharmaceutical pipeline, the need for better delivery systems grows. Many biologics are fragile and short-lived in the body. Peptide hydrogels could serve as injectable depots that protect these drugs and release them slowly, potentially reducing injection frequency and improving patient compliance. This is especially important for the growing class of peptide therapeutics.

Drug delivery is one of the biggest bottlenecks in getting peptide therapeutics to patients. Many promising peptides fail not because they don't work, but because they break down too fast or can't reach their target. Peptide hydrogels represent an elegant solution — using peptides themselves as the delivery vehicle for other peptide drugs. As the peptide therapeutics market grows, these self-assembling delivery platforms could become critical enabling technology.

This is a review article that summarizes the state of the field rather than reporting new experimental data. Most peptide hydrogel drug delivery systems discussed are in preclinical stages, and the review does not provide a systematic assessment of which systems have advanced to human trials. The translation from laboratory demonstrations to clinical use faces significant regulatory and manufacturing challenges that are not deeply explored.