angiogenesis inhibitor
Meaning of angiogenesis inhibitor: A drug that starves growth by cutting the signal for new plumbing, given to far more people for eye disease than for cancer.
Definition of angiogenesis inhibitor
An angiogenesis inhibitor is a drug that blocks the growth of new blood vessels by interfering with the chemical signals that trigger it, rather than by damaging vessels already in place. Most act against vascular endothelial growth factor, either by mopping up the signal, occupying its receptor, or switching off the receptor's internal relay. They are given into a vein, into the eye, or by mouth.
How do the different types work?
| Approach | What it does | How it is given |
|---|---|---|
| Antibody against the signal | Traps the growth factor before it reaches a receptor | Injection |
| Decoy receptor | Binds the growth factor with a manufactured receptor piece | Injection |
| Receptor antibody | Occupies the receptor on the vessel lining cell | Injection |
| Kinase inhibitor tablet | Silences the receptor's internal relay inside the cell | By mouth |
All four leave established vessels alone. Angiogenesis is a construction process, and these drugs remove the order to build rather than demolishing what stands, which is why the effect lasts only while treatment continues and why growth commonly restarts once it stops.
Why are they so heavily used in eye disease?
Because a small volume placed directly into the eye reaches the target and stays there. In wet age-related macular degeneration, abnormal vessels grow under the retina and leak fluid and blood into the part of the eye responsible for reading and recognizing faces. Blocking the signal dries the leak and stabilizes vision in most cases, and in a fair share improves it. The same injections treat swelling of the retina in diabetes and after a blocked retinal vein. Repeat injections are needed for as long as the drive to grow vessels persists, so treatment is measured in years.
What do they achieve in cancer?
Less than the theory once promised. A tumor beyond a few millimeters across cannot get enough oxygen by diffusion and must recruit a supply, so cutting that supply looked like a way to starve any solid tumor. In practice these drugs seldom shrink tumors on their own; used within anticancer therapy they add modest time alongside chemotherapy in cancers of the bowel, kidney, lung and liver. Tumors also adapt, switching to other growth signals or growing along vessels that already exist.
Also known as
Used in a sentence
An angiogenesis inhibitor was given by injection into the eye.
Good to know
These drugs suppress the signal for new vessel growth and do not remove vessels already formed, so the effect lasts only while treatment continues and vessel growth commonly resumes after it is stopped.
Word origin
Where “angiogenesis inhibitor” comes from
From Greek angeion, vessel, and genesis, coming into being, with inhibitor from Latin inhibere, to hold back.