Abiraterone Acetate (4 brand names, 1 dosage form, 1 route)
Available dosage forms: TABLET.
Routes of administration: ORAL.
Brand Names
- ABIRATERONE ACETATE
- AKEEGA
- YONSA
- ZYTIGA
Indications and Usage
Abiraterone Acetate is indicated in combination with methylprednisolone for the treatment of patients with metastatic castration-resistant prostate cancer.
Contraindications
None.
Adverse Reactions
The following are discussed in more detail in other sections of the labeling: Hypokalemia, Fluid Retention, and Cardiovascular Adverse Reactions due to Mineralocorticoid Excess [see Warnings and Precautions ( 5.1 )]. Adrenocortical Insufficiency [see Warnings and Precautions ( 5.2 )]. Hepatotoxicity [see Warnings and Precautions ( 5.3 )]. Increased Fractures and Mortality in Combination with Radium Ra 223 Dichloride [see Warnings and Precautions ( 5.4 )].
Mechanism of Action
Abiraterone acetate is converted in vivoto abiraterone, an androgen biosynthesis inhibitor, that inhibits 17 α-hydroxylase/C17,20-lyase (CYP17). This enzyme is expressed in testicular, adrenal, and prostatic tumor tissues and is required for androgen biosynthesis. CYP17 catalyzes two sequential reactions: 1) the conversion of pregnenolone and progesterone to their 17α-hydroxy derivatives by 17α-hydroxylase activity and 2) the subsequent formation of dehydroepiandrosterone (DHEA) and androstenedione, respectively, by C17,20-lyase activity. DHEA and androstenedione are androgens and are precursors of testosterone. Inhibition of CYP17 by abiraterone can also result in increased mineralocorticoid production by the adrenals [see Warnings and Precautions ( 5.1 )]. Androgen sensitive prostatic carcinoma responds to treatment that decreases androgen levels. Androgen deprivation therapies, such as treatment with GnRH agonists or orchiectomy, decrease androgen production in the testes but do not affect androgen production by the adrenals or in the tumor. Abiraterone acetate decreased serum testosterone and other androgens in patients in the placebo-controlled clinical trial. It is not necessary to monitor the effect of Abiraterone Acetate on serum testosterone levels. Changes in serum prostate specific antigen (PSA) levels may be observed but have not been shown to correlate with clinical benefit in individual patients.
Overdosage
Human experience of overdose with Abiraterone Acetate is limited. There is no specific antidote. In the event of an overdose, stop Abiraterone Acetate, undertake general supportive measures, including monitoring for arrhythmias and cardiac failure and assess liver function.