abiraterone acetate
Meaning of abiraterone acetate: A prostate cancer tablet that shuts down testosterone production everywhere in the body, not only in the testicles.
Definition of abiraterone acetate
Abiraterone acetate is a prescription medicine for advanced prostate cancer, taken by mouth alongside a steroid. It blocks an enzyme called CYP17, which every tissue that makes androgens depends on. Testosterone production therefore stops in the adrenal glands and within the tumor itself, not only in the testicles, and prostate cancer cells that still depend on androgens are starved of them.
Why block androgen production a second time?
Standard hormone treatment for prostate cancer switches off the testicles, which supply most testosterone. Cancer that returns after that is called castration resistant, a label that overstates matters, because most such tumors have not stopped depending on androgens. They have found other sources: small amounts made by the adrenal glands, and androgens the tumor manufactures for itself. Blocking the shared enzyme closes all of these routes at once, which is why it works when the first approach has failed.
Why is a steroid taken with it?
| Consequence of blocking CYP17 | Effect |
|---|---|
| Cortisol production falls | The pituitary drives the adrenal glands harder |
| Precursor hormones build up | Salt and water retention, low potassium, raised blood pressure |
| Replacement steroid given | Restores the missing signal and limits that buildup |
What else is worth knowing about it?
The acetate form is a delivery convenience: the body strips the acetate off after absorption to release abiraterone itself. Absorption is strongly affected by food, and taking it with a meal raises blood levels far above the intended range, which is why the timing relative to eating is specified. Liver enzymes are monitored, since raised readings are common and occasionally serious, and blood pressure and potassium are checked because of the hormone buildup described above. Fatigue, joint swelling and hot flashes are frequent.
Where does it sit among prostate cancer treatments?
It is one of several drugs that extended the treatment of advanced prostate cancer beyond simple hormone suppression. Others block the androgen receptor rather than androgen production, and chemotherapy remains an option alongside. Its use has moved earlier over time, from disease that has progressed after chemotherapy to earlier stages of hormone sensitive disease, based on trials showing longer survival. It is a licensed treatment rather than an investigational one.
Also known as
Used in a sentence
Abiraterone acetate with prednisone was started after progression on hormone therapy alone.
Good to know
Abiraterone is an approved treatment for advanced prostate cancer rather than an investigational agent, and it is taken with a steroid because blocking CYP17 also lowers cortisol production.