“Regular infusions of replacement IDS has been the standard of care [for Hunter syndrome] for the past two decades, and it protects important organs such as the liver and kidneys from damage. But without help, the large enzyme can’t make it through the protective barrier that separates the blood from one of the most important organs — the brain.

For Gordon’s children, that help comes from an innovative molecular transport system, a chemical tag attached to IDS that shuttles it through the tightly joined cells that make up the blood–brain barrier. Several such shuttles, which take advantage of natural transport systems in the brain, are now being developed. With the ability to move large biological drugs — including antibodies, proteins and the viruses used in gene therapy — these shuttles promise to revolutionize neuropharmacology. And that’s not just for rare diseases such as Hunter syndrome, but also for cancer, Alzheimer’s disease and other common brain disorders.

The field is in its infancy, and much is left to discover about how to target large therapeutic molecules to the exact spots in the brain where they’re needed, says James Gorman, principal investigator of the Wyss Institute Brain Targeting Program at Harvard University in Boston, Massachusetts. Nevertheless, the excitement is palpable. 

‘It seems like every major company in this space has a programme to develop brain shuttles,’ he says.”

From Nature.