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Quick facts
- How it is given
- oral
- Type
- human prescription drug
- RxNorm ID
- 1100075
We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.
What it is used to treat
Abiraterone acetate tablets are indicated in combination with prednisone for the treatment of patients with Metastatic castration-resistant prostate cancer (CRPC) Metastatic high-risk castration-sensitive prostate cancer (CSPC) Abiraterone acetate tablet is a CYP17 inhibitor indicated in combination with prednisone for the treatment of patients with metastatic castration-resistant prostate cancer (CRPC). ( 1) metastatic high-risk castration-sensitive prostate cancer (CSPC). ( 1 )
About this medicine
Abiraterone acetate USP, the active ingredient of abiraterone acetate tablets, USP is the acetyl ester of abiraterone. Abiraterone is an inhibitor of CYP17 (17α-hydroxylase/C17,20-lyase). Each abiraterone acetate tablet, USP contains 250 mg or 500 mg of abiraterone acetate USP. Abiraterone acetate USP is designated chemically as (3β)17-(3-pyridinyl) androsta-5,16-dien-3-yl acetate and its structure is: Abiraterone acetate USP is a white to off-white, non-hygroscopic, crystalline powder. Its molecular formula is C 26 H 33 NO 2 and it has a molecular weight of 391.55. Abiraterone acetate USP is a lipophilic compound with an octanol-water partition coefficient of 5.12 (Log P) and is practically insoluble in water. The pKa of the aromatic nitrogen is 5.19. Abiraterone acetate tablets are available in 250 mg and 500 mg film-coated tablets with the following inactive ingredients: 250 mg film-coated tablets: colloidal silicon dioxide, croscarmellose sodium, hypromellose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, polyethylene glycol, povidone, sodium lauryl sulfate and titanium dioxide. 500 mg film-coated tablets: colloidal silicon dioxide, croscarmellose sodium, hypromellose, iron oxide black, iron oxide red, lactose monohydrate, magnesium stearate, polyethylene glycol, polyvinyl alcohol, silicified microcrystalline cellulose, sodium lauryl sulfate, talc and titanium dioxide. FDA approved dissolution test specifications differ from USP.
How it works
12.1 Mechanism of Action Abiraterone acetate is converted in vivo to 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.
Warnings and cautions
Mineralocorticoid excess: Closely monitor patients with cardiovascular disease. Control hypertension and correct hypokalemia before treatment. Monitor blood pressure, serum potassium and symptoms of fluid retention at least monthly. ( 5.1 ) Adrenocortical insufficiency: Monitor for symptoms and signs of adrenocortical insufficiency. Increased dosage of corticosteroids may be indicated before, during and after stressful situations. ( 5.2 ) Hepatotoxicity: Can be severe and fatal. Monitor liver function and modify, interrupt, or discontinue abiraterone acetate dosing as recommended. ( 5.3 ) Increased fractures and mortality in combination with radium Ra 223 dichloride: Use of abiraterone acetate plus prednisone/prednisolone in combination with radium Ra 223 dichloride is not recommended. (5.4) Embryo-Fetal Toxicity: Abiraterone acetate can cause fetal harm. Advise males with female partners of reproductive potential to use effective contraception. ( 5.5 , 8.1 , 8.3 ) Hypoglycemia: Severe hypoglycemia has been reported in patients with pre-existing diabetes who are taking medications containing thiazolidinediones (including pioglitazone) or repaglinide. Monitor blood glucose in patients with diabetes and assess if antidiabetic agent dose modifications are required. (5.6) 5.1 Hypokalemia, Fluid Retention, and Cardiovascular Adverse Reactions due to Mineralocorticoid Excess Abiraterone acetate may cause hypertension, hypokalemia, and fluid retention as a consequence of increased mineralocorticoid levels resulting from CYP17 inhibition [see Clinical Pharmacology ( 12.1 )]. Monitor patients for hypertension, hypokalemia, and fluid retention at least once a month. Control hypertension and correct hypokalemia before and during treatment with abiraterone acetate. In the combined data from 4 placebo-controlled trials using prednisone 5 mg twice daily in combination with 1,000 mg abiraterone acetate daily, grades 3 to 4 hypokalemia were detected in 4% of patients on the abiraterone acetate arm and 2% of patients on the placebo arm. Grades 3 to 4 hypertension were observed in 2% of patients each arm and grades 3 to 4 fluid retention in 1% of patients each arm. […]
Reported side effects
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) ]. The most common adverse reactions (≥10%) are fatigue, arthralgia, hypertension, nausea, edema, hypokalemia, hot flush, diarrhea, vomiting, upper respiratory infection, cough, and headache. ( 6.1 ) The most common laboratory abnormalities (>20%) are anemia, elevated alkaline phosphatase, hypertriglyceridemia, lymphopenia, hypercholesterolemia, hyperglycemia, and hypokalemia. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Dr. Reddy’s Laboratories Inc., at 1-888-375-3784 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trial Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. Two randomized placebo-controlled, multicenter clinical trials (COU-AA-301 and COU-AA302) enrolled patients who had metastatic CRPC in which abiraterone acetate was administered orally at a dose of 1,000 mg daily in combination with prednisone 5 mg twice daily in the active treatment arms. Placebo plus prednisone 5 mg twice daily was given to patients on the control arm. Another randomized placebo-controlled, multicenter clinical trial (LATITUDE) enrolled patients who had metastatic high-risk CSPC in which abiraterone acetate was administered at a dose of 1,000 mg daily in combination with prednisone 5 mg once daily. Placebos were administered to patients in the control arm. Additionally, two other randomized, placebo-controlled trials were conducted in patients with metastatic CRPC. […]
Interactions with other medicines
CYP3A4 Inducers: Avoid concomitant strong CYP3A4 inducers during abiraterone acetate treatment. If a strong CYP3A4 inducer must be co-administered, increase the abiraterone acetate dosing frequency. ( 2.5 , 7.1 ) CYP2D6 Substrates: Avoid co-administration of abiraterone acetate with CYP2D6 substrates that have a narrow therapeutic index. If an alternative treatment cannot be used, exercise caution and consider a dose reduction of the concomitant CYP2D6 substrate. ( 7.2 ) 7.1 Drugs that Inhibit or Induce CYP3A4 Enzymes Based on in vitro data, abiraterone acetate is a substrate of CYP3A4. In a dedicated drug interaction trial, co-administration of rifampin, a strong CYP3A4 inducer, decreased exposure of abiraterone by 55%. Avoid concomitant strong CYP3A4 inducers during abiraterone acetate treatment. If a strong CYP3A4 inducer must be co-administered, increase the abiraterone acetate dosing frequency [see Dosage and Administration ( 2.5 ) and Clinical Pharmacology ( 12.3 )]. In a dedicated drug interaction trial, co-administration of ketoconazole, a strong inhibitor of CYP3A4, had no clinically meaningful effect on the pharmacokinetics of abiraterone [see Clinical Pharmacology ( 12.3 )]. 7.2 Effects of Abiraterone on Drug Metabolizing Enzymes Abiraterone acetate is an inhibitor of the hepatic drug-metabolizing enzymes CYP2D6 and CYP2C8. In a CYP2D6 drug-drug interaction trial, the C max and AUC of dextromethorphan (CYP2D6 substrate) were increased 2.8- and 2.9-fold, respectively, when dextromethorphan was given with abiraterone acetate 1,000 mg daily and prednisone 5 mg twice daily. Avoid co-administration of abiraterone acetate with substrates of CYP2D6 with a narrow therapeutic index (e.g., thioridazine). If alternative treatments cannot be used, consider a dose reduction of the concomitant CYP2D6 substrate drug [see Clinical Pharmacology ( 12.3 )]. In a CYP2C8 drug-drug interaction trial in healthy subjects, the AUC of pioglitazone (CYP2C8 substrate) was increased by 46% when pioglitazone was given together with a single dose of 1,000 mg abiraterone acetate. […]
Use in specific groups
• Do not use abiraterone acetate tablets in patients with baseline severe hepatic impairment (Child-Pugh Class C). ( 8.6 ) 8.1 Pregnancy Risk Summary The safety and efficacy of abiraterone acetate have not been established in females. Based on findings from animal studies and the mechanism of action, abiraterone acetate can cause fetal harm and potential loss of pregnancy. There are no human data on the use of abiraterone acetate in pregnant women. In animal reproduction studies, oral administration of abiraterone acetate to pregnant rats during organogenesis caused adverse developmental effects at maternal exposures approximately ≥ 0.03 times the human exposure (AUC) at the recommended dose (see Data). Data Animal Data In an embryo-fetal developmental toxicity study in rats, abiraterone acetate caused developmental toxicity when administered at oral doses of 10, 30 or 100 mg/kg/day throughout the period of organogenesis (gestational days 6 to 17). Findings included embryo-fetal lethality (increased post implantation loss and resorptions and decreased number of live fetuses), fetal developmental delay (skeletal effects) and urogenital effects (bilateral ureter dilation) at doses ≥10 mg/kg/day, decreased fetal ano-genital distance at ≥30 mg/kg/day, and decreased fetal body weight at 100 mg/kg/day. Doses ≥10 mg/kg/day caused maternal toxicity. The doses tested in rats resulted in systemic exposures (AUC) approximately 0.03, 0.1 and 0.3 times, respectively, the AUC in patients. 8.2 Lactation Risk Summary The safety and efficacy of abiraterone acetate have not been established in females. There is no information available on the presence of abiraterone in human milk, or on the effects on the breastfed child or milk production. 8.3 Females and Males of Reproductive Potential Contraception Males Based on findings in animal reproduction studies and its mechanism of action, advise males with female partners of reproductive potential to use effective contraception during treatment and for 3 weeks after the final dose of abiraterone acetate [see Use in Specific Populations ( 8.1 )]. […]
If too much is taken
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.
Before you take anything new
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This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 17 March 2025. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.