A drug can switch a protein off, but it can't make the body throw the protein away
The old claim turned out to be wrong and was rejected by evidence.
TaughtMedicines work by binding a target protein and blocking it, like a key jammed in a lock. The drug has to stay bound to keep working, and proteins the body considers 'undruggable', with no good pocket to grab, are simply out of reach.
NowOn 1 May 2026 the FDA approved vepdegestrant (Veppanu), the first PROTAC ever authorized anywhere. Instead of blocking its target, it tags the protein for the cell's own disposal machinery, so the protein is destroyed rather than merely occupied.
What actually happened
A PROTAC, proteolysis-targeting chimera, is a two-headed molecule: one end grabs the target protein, the other grabs the cell's ubiquitin-proteasome system, the built-in shredder. It drags the two together, the cell tags the target for demolition, and the drug then floats free to do it again. One molecule can take out many copies of the protein, and it can work on targets that offered no pocket to block.
Vepdegestrant degrades the estrogen receptor in a form of advanced breast cancer, and its approval turns a decade of laboratory promise into a shipping medicine. The idea had been taught as a fascinating concept that kept not quite reaching patients. That caveat is now retired: the flat statement that drugs can only inhibit proteins, never delete them, is false as of 2026.
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Who was taught this
Still standard through 2026, so anyone who finished school between 1950 and 2026 learned the earlier version.