Abiraterone Acetate
FDA Drug Information • Also known as: Abiraterone, Abiraterone Acetate, Abirtega, Yonsa, Zytiga
- Brand Names
- Abiraterone, Abiraterone Acetate, Abirtega, Yonsa, Zytiga
- Dosage Form
- POWDER
- Product Type
- BULK INGREDIENT
Description
11 DESCRIPTION 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 contains either 250 mg or 500 mg of abiraterone acetate, USP. Abiraterone acetate 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 or almost white, non-hygroscopic, solid powder and freely soluble in methylene chloride, tetrahydrofuran, and toluene, soluble in methanol, ethanol, ethyl acetate, isobutyl methyl ketone, N,N-dimethylformamide, and acetone, sparingly soluble in acetonitrile and dimethyl sulfoxide, slightly soluble in hexane, very slightly soluble in 0.1 N hydrochloric acid and practically insoluble aqueous media over a wide range of pH values. Its molecular formula is C 26 H 33 NO 2 and it has a molecular weight of 391.6 g/mol. Abiraterone Acetate Tablets, USP are available in 500 mg film-coated tablets and 250 mg uncoated tablets with the following inactive ingredients:
500 mg film-coated tablets: colloidal silicon dioxide, croscarmellose sodium, lactose monohydrate, magnesium stearate, microcrystalline cellulose, povidone K–30 and sodium lauryl sulfate. The coating, Opadry II 85F500121 Purple, contains iron oxide black, iron oxide red, polyethylene glycol, polyvinyl alcohol-part hydrolyzed, talc, and titanium dioxide. 250 mg uncoated tablets: colloidal silicon dioxide, croscarmellose sodium, lactose monohydrate, magnesium stearate, microcrystalline cellulose, povidone and sodium lauryl sulfate. FDA approved dissolution test specifications differ from USP. Structure.jpgWhat Is Abiraterone Acetate Used For?
1 INDICATIONS AND USAGE 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 tablets are 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 )Dosage and Administration
2 DOSAGE AND ADMINISTRATION Metastatic castration-resistant prostate cancer:
Abiraterone acetate tablets 1,000 mg orally once daily with prednisone 5 mg orally twice daily. ( 2.1 ) Metastatic castration-sensitive prostate cancer: Abiraterone acetate tablets 1,000 mg orally once daily with prednisone 5 mg orally once daily. ( 2.2 ) Patients receiving abiraterone acetate tablets should also receive a gonadotropin-releasing hormone (GnRH) analog concurrently or should have had bilateral orchiectomy. Abiraterone acetate tablets must be taken as a single dose once daily on an empty stomach. Do not eat food 2 hours before and 1 hour after taking abiraterone acetate tablets. The tablets must be swallowed whole with water. Do not crush or chew tablets. ( 2.3 ) Dose Modification: For patients with baseline moderate hepatic impairment (Child-Pugh Class B), reduce the abiraterone acetate tablets starting dose to 250 mg once daily. ( 2.4 ) For patients who develop hepatotoxicity during treatment, hold abiraterone acetate tablets until recovery. Retreatment may be initiated at a reduced dose. Abiraterone acetate tablets should be discontinued if patients develop severe hepatotoxicity. ( 2.4 ) 2.1 Recommended Dose for Metastatic CRPC The recommended dose of abiraterone acetate is 1,000 mg (two 500 mg tablets or four 250 mg tablets) orally once daily with prednisone 5 mg orally twice daily. 2.2 Recommended Dose for Metastatic High-risk CSPC The recommended dose of abiraterone acetate is 1,000 mg (two 500 mg tablets or four 250 mg tablets) orally once daily with prednisone 5 mg administered orally once daily. 2.3 Important Administration Instructions Patients receiving abiraterone acetate tablets should also receive a gonadotropin-releasing hormone (GnRH) analog concurrently or should have had bilateral orchiectomy. Abiraterone acetate tablets must be taken as a single dose once daily on an empty stomach. Do not eat food 2 hours before and 1 hour after taking abiraterone acetate tablets. The tablets must be swallowed whole with water. Do not crush or chew tablets. 2.4 Dose Modification Guidelines in Hepatic Impairment and Hepatotoxicity Hepatic Impairment In patients with baseline moderate hepatic impairment (Child-Pugh Class B), reduce the recommended dose of abiraterone acetate tablets to 250 mg once daily. In patients with moderate hepatic impairment monitor ALT, AST, and bilirubin prior to the start of treatment, every week for the first month, every two weeks for the following two months of treatment and monthly thereafter. If elevations in ALT and/or AST greater than 5 × upper limit of normal (ULN) or total bilirubin greater than 3 × ULN occur in patients with baseline moderate hepatic impairment, discontinue abiraterone acetate tablets and do not re-treat patients with abiraterone acetate tablets [see Use in Specific Populations ( 8.6 ) and Clinical Pharmacology ( 12.3 )]. Do not use abiraterone acetate tablets in patients with baseline severe...Side Effects (Adverse Reactions)
6 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 )] . 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 Glenmark Pharmaceuticals Inc., USA at 1 (888) 721-7115 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-AA-302) 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. A third 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. The safety data pooled from 2,230 patients in the 5 randomized controlled trials constitute the basis for the data presented in the Warnings and Precautions, Grade 1 to 4 adverse reactions, and Grade 1 to 4 laboratory abnormalities. In all trials, a gonadotropin-releasing hormone (GnRH) analog or prior orchiectomy was required in both arms. In the pooled data, median treatment duration was 11 months (0.1, 43) for abiraterone acetate-treated patients and 7.2 months (0.1, 43) for placebo-treated patients. The most common adverse reactions (≥ 10%) that occurred more commonly (> 2%) in the abiraterone acetate arm were fatigue, arthralgia, hypertension, nausea, edema, hypokalemia, hot flush, diarrhea, vomiting, upper respiratory infection, cough, and headache. The most common laboratory abnormalities (> 20%) that occurred more commonly (≥ 2%) in the abiraterone acetate arm were anemia, elevated alkaline phosphatase, hypertriglyceridemia, lymphopenia, hypercholesterolemia, hyperglycemia, and hypokalemia. Grades 3 to 4 adverse events were reported for 53% of patients in the abiraterone acetate arm and 46% of patients in the placebo arm. Treatment discontinuation was reported in 14% of patients in the abiraterone acetate arm and 13% of patients in the placebo arm. The common adverse events (≥ 1%) resulting in discontinuation of abiraterone acetate and prednisone were hepatotoxicity and cardiac disorders. Deaths associated with treatment-emergent adverse events were reported for 7.5% of patients in the abiraterone acetate arm and 6.6% of patients in the placebo arm. Of the patients in the abiraterone acetate arm, the most common cause of death was disease progression (3.3%). Other reported causes of death in ≥ 5 patients included pneumonia, cardio-respiratory arrest, death (no additional information), and general physical health deterioration....Drug Interactions
7 DRUG INTERACTIONS
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. Therefore, patients should be monitored closely for signs of toxicity related to a CYP2C8 substrate with a narrow therapeutic index if used concomitantly with abiraterone acetate [see Clinical Pharmacology ( 12.3 ) and Warnings and Precautions ( 5.6 )].Contraindications
4 CONTRAINDICATIONS None.
None ( 4 )Pregnancy and Breastfeeding
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.
Overdosage
10 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.
How Supplied
16 HOW SUPPLIED/STORAGE AND HANDLING Abiraterone Acetate Tablets, USP are available in the strengths and packages listed below: . Abiraterone acetate 500 mg film-coated Tablets Brownish pink, oval shaped, film-coated tablets, debossed with a ‘G’ on one side and ‘121’ on the other side. Bottles of 60 with child-resistant closure, NDC 68462-882-60 . Abiraterone acetate 250 mg uncoated Tablets White to off-white, oval shaped, uncoated tablets debossed with a ‘G’ on one side and ‘135’ on the other side. Bottles of 120 with child-resistant closure, NDC 68462-135-08 Storage and Handling Store at 20°C to 25°C (68°F to 77°F); excursions permitted from 15°C to 30°C (59°F to 86°F) [see USP Controlled Room Temperature]. Keep out of reach of children. Based on its mechanism of action, abiraterone acetate may harm a developing fetus. Women who are pregnant or women who may be pregnant should not handle abiraterone acetate 250 mg uncoated tablets or other abiraterone acetate tablets if broken, crushed, or damaged without protection, e.g., gloves [see Use in Specific Populations ( 8.1 )] .
About This Information
This drug information is sourced from FDA-approved labeling via the openFDA database. It is intended for educational and reference purposes only. This is not medical advice. Always consult your healthcare provider before making decisions about medication. Drug information may be updated by the FDA; check with your pharmacist for the most current information.
What are side effects?
Side effects are unwanted reactions that can occur when taking a medication. They range from mild (headache, nausea) to severe (allergic reactions, organ damage). Not everyone experiences side effects, and severity varies. Report any concerning side effects to your doctor.
What are drug interactions?
Drug interactions occur when a medication is affected by another drug, food, or supplement. Interactions can make medications less effective or cause dangerous side effects. Always tell your doctor about all medications and supplements you take.