Abiraterone acetate (Abiranamo) 250 mg, 120 tablets: profile, composition and research

Reference page for Abiraterone acetate (Abiranamo) 250 mg, 120 tablets. Active substance: Абиратерона ацетат / Abiraterone acetate.

Key facts

What abiraterone acetate is

Abiraterone acetate is an oral antineoplastic medicine classed among inhibitors of androgen synthesis. It does not act on a tumour directly; instead it interferes with the production of male sex hormones in the body, which places it among agents that act on the tumour through hormonal pathways.

The substance is supplied as 250 mg tablets. The manufacturer states that under the standard regimen the daily dose is 1000 mg, which is four tablets. A pack of 120 tablets covers roughly one month of continuous therapy at that rate. The schedule itself is set by a physician.

The medicine is used in advanced prostate cancer, when the tumour has already spread beyond the organ. Prescribing and running the treatment belong to an oncologist; such products are not taken on one's own. Treatment is supervised by a specialist throughout.

How it affects androgen production

The target enzyme CYP17A1

Androgens are built from cholesterol through a chain of successive reactions, and the enzyme CYP17A1 is one of its key links. It catalyses conversions without which testosterone and its precursors are not formed. The enzyme operates in the adrenal glands and the tumour.

What abiraterone acetate does

The molecule binds this enzyme and inhibits it irreversibly. As a result androgen synthesis is restricted not only in the testes but also in other tissues, including the adrenal glands and the tumour itself, which can also produce hormones.

Why that matters in resistance

In castration-resistant cancer the tumour keeps growing even when testosterone is suppressed, because it makes androgens on its own. Blocking CYP17A1 removes that source and reduces the hormonal support for growth. That is the rationale behind this drug class.

Approved uses

The prescribing information names metastatic castration-resistant prostate cancer and, in combination with other agents, metastatic hormone-sensitive disease. The medicine is used in adult men once the diagnosis has been established. Prescribing is possible only on a specialist's decision.

Treatment is usually combined with a low dose of a glucocorticoid, most often prednisolone: suppressing CYP17A1 raises adrenal hormone output, and that support helps to balance the effect. The exact combinations and their composition are chosen by a physician.

Before and during treatment, liver function, blood pressure, blood potassium and PSA activity as a marker of response are monitored. The schedule and the duration are set by an oncologist, not by a reference page. Monitoring tests are run regularly throughout treatment.

What the research shows

The efficacy of abiraterone acetate was studied in several large randomised trials. In COU-AA-301, among patients with castration-resistant cancer after chemotherapy, adding the medicine to prednisolone was accompanied by longer overall survival than placebo.

In COU-AA-302, in men who had not yet received cytotoxics, the combination also showed an advantage on several endpoints. In LATITUDE, in patients with newly diagnosed metastatic hormone-sensitive disease, adding the medicine to hormonal therapy increased progression-free and overall survival.

One thread runs through these studies: the medicine is given by a specialist within a defined clinical situation, not for prostate cancer in general. Tolerability and the adverse-event profile were described in detail, including effects on the liver, blood pressure and potassium balance.

Published research

Primary sources, verified against PubMed:

• Abiraterone plus Prednisone in Metastatic, Castration-Sensitive Prostate Cancer., PubMed 28578607 (The New England journal of medicine, 2017).
• Abiraterone acetate for treatment of metastatic castration-resistant prostate cancer: final overall survival analysis of the COU-AA-301 randomised, double-blind, placebo-controlled phase 3 study., PubMed 22995653 (The Lancet. Oncology, 2012).
• Abiraterone in metastatic prostate cancer without previous chemotherapy., PubMed 23228172 (The New England journal of medicine, 2013).
• Abiraterone acetate plus prednisone versus placebo plus prednisone in chemotherapy-naive men with metastatic castration-resistant prostate cancer (COU-AA-302): final overall survival analysis of a randomised, double-blind, placebo-controlled phase 3 study., PubMed 25601341 (The Lancet. Oncology, 2015).

Listed for reference. Publication of a study is not a claim about this particular product.

Precautions

• This is a prescription medicine. Prescribing, dosing and monitoring belong to an oncologist.
• Treatment affects the liver: rises in transaminases and bilirubin are possible, so monitoring blood tests are run.
• Through its effect on adrenal hormones, higher blood pressure, fluid retention and low potassium are possible.
• The medicine is not used in women; with a partner who is or may become pregnant, reliable contraception is needed.
• In pregnancy the medicine can harm the fetus, which is why use in women is excluded.
• Tell your doctor about every other medicine you take: interactions are possible.

Frequently asked