Biology
The Blood-Brain Barrier and Drug Delivery
Quick fact
About 98% of small-molecule drugs and nearly 100% of large-molecule biologics cannot cross the blood-brain barrier, making neurological drug development exceptionally challenging.
Why this is interesting
Your brain is shielded by a nearly impenetrable fortress—but that same fortress also blocks life-saving medicines. Why does the body protect itself so well, and yet cause so many treatment failures?