Strategies for Delivering Peptide Drugs Across the Blood-Brain Barrier | Research

The takeaway

Receptor-mediated transcytosis using cell-penetrating peptides, targeting peptides, or antibodies enables drug delivery across the blood-brain barrier for treating CNS diseases.

3 receptor targets
Transferrin, LDL, and insulin receptors on brain endothelial cells used for receptor-mediated drug transport across the BBB

What the researchers found

RMT strategies using CPPs, targeting peptides, or antibodies that bind TfR, LDLR, or InsR on brain endothelial cells can overcome the BBB and deliver therapeutics to the brain.

Why it matters

The blood-brain barrier blocks most drugs from reaching the brain, limiting treatment options for Alzheimer's, Parkinson's, and other neurological diseases. RMT-based delivery could unlock therapies currently unable to reach their targets.

The numbers in context

3 key receptors (TfR, LDLR, InsR); 3 ligand types; several clinical candidates

How the study worked

Narrative review of RMT mechanisms, targeting ligand types, receptor biology, and clinical development status of BBB-crossing drug conjugates.

Who was studied

Review article (no study population)

What this study cannot tell us

Review article. Many strategies are preclinical. Achieving sufficient brain concentrations while avoiding peripheral effects remains challenging.

How to read the evidence

Review of preclinical and clinical delivery strategies. Provides a comprehensive framework but most approaches are still in development.

When this study was published

Published in 2020. BBB delivery research has continued to advance with new clinical candidates.

The bigger picture

Solving the BBB delivery problem is one of the biggest challenges in neurological drug development. Peptide-based targeting strategies are among the most promising approaches.

Questions still open

Which receptor target provides the best brain penetration?
Can peptide-based BBB delivery achieve therapeutic drug concentrations?
How do targeting efficiency and specificity compare between CPPs and mAbs?

Common questions

What is the blood-brain barrier and why is it a problem?

The BBB is a tight layer of cells lining brain blood vessels that blocks most drugs from entering the brain. While it protects the brain from toxins, it also prevents potentially life-saving medications from reaching brain targets in diseases like Alzheimer's.

How do peptides help drugs cross the BBB?

Peptides can be attached to drugs as targeting ligands. These peptides bind to specific receptors on BBB cells, triggering a transport process called transcytosis that carries the drug-peptide conjugate across the barrier and into the brain.

Read the original research

Smart Strategies for Therapeutic Agent Delivery into Brain across the Blood-Brain Barrier Using Receptor-Mediated Transcytosis.

Chemical & pharmaceutical bulletin, 68(4), 316-325

View on PubMed ↗Publisher’s paper ↗

Citation

Tashima, Toshihiko. (2020). Smart Strategies for Therapeutic Agent Delivery into Brain across the Blood-Brain Barrier Using Receptor-Mediated Transcytosis.. Chemical & pharmaceutical bulletin, 68(4), 316-325. https://doi.org/10.1248/cpb.c19-00854