Abiraterone Acetate Tablets – Oral Treatment for Metastatic Prostate Cancer

Abiraterone acetate tablets are oral medication approved for use in combination with prednisone to treat metastatic prostate cancer. It is specifically indicated for metastatic castration-resistant prostate cancer (CRPC) and metastatic high-risk castration-sensitive prostate cancer (CSPC).

• Treatment of metastatic castration-resistant prostate cancer in adult males, in combination with prednisone.
• Treatment of metastatic high-risk castration-sensitive prostate cancer in adult males, in combination with prednisone.

Abiraterone Acetate

Abiraterone acetate works by inhibiting CYP17, an enzyme critical to androgen production. By blocking this enzyme, it reduces androgen synthesis which fuels the growth of prostate cancer cells, thereby helping to control the disease.

Recommended Dosage

• For metastatic castration-resistant prostate cancer (CRPC): 1,000 mg (four 250 mg tablets) orally once daily with prednisone 5 mg orally twice daily.
• For metastatic high-risk castration-sensitive prostate cancer (CSPC): 1,000 mg (four 250 mg tablets) orally once daily with prednisone 5 mg orally once daily.

Administration Instructions

• Take abiraterone acetate tablets as a single daily dose on an empty stomach—do not eat for 2 hours before and 1 hour after dosing.
• Swallow tablets whole with water; do not crush or chew.
• Concurrent treatment with a gonadotropin-releasing hormone (GnRH) analog is required or ensure that bilateral orchiectomy has been performed.

Dose Modifications

• In patients with moderate hepatic impairment (Child-Pugh Class B), reduce dose to 250 mg once daily and monitor liver function closely.
• For hepatotoxicity during treatment (ALT/AST >5x ULN or total bilirubin >3x ULN), interrupt therapy until recovery, then reinitiate at reduced doses (750 mg, then 500 mg if needed). Discontinue if hepatotoxicity recurs at 500 mg or if ALT >3x ULN and bilirubin >2x ULN occur concurrently without other causes.
• If a strong CYP3A4 inducer must be co-administered, increase abiraterone acetate dosing frequency to twice daily during co-administration and revert after discontinuation.

None specified.

Major Warnings and Precautions

• Mineralocorticoid Excess: Abiraterone can cause hypertension, hypokalemia, and fluid retention due to increased mineralocorticoid levels. Monitor blood pressure, potassium, and fluid status monthly. Control hypertension and correct hypokalemia before and during treatment, especially in patients with cardiovascular conditions.
• Hepatotoxicity: Severe liver toxicity including acute liver failure and death can occur. Liver enzymes and bilirubin should be monitored before treatment, every 2 weeks for the first 3 months, then monthly. Interrupt or discontinue therapy based on liver test results.
• Adrenocortical Insufficiency: Occurs rarely; monitor for symptoms especially if prednisone dose changes or during stress; steroid dose adjustments may be necessary.
• Increased Fractures and Mortality: Use with radium Ra 223 dichloride is not recommended outside clinical trials due to increased fractures and deaths.
• Embryo-Fetal Toxicity: Can cause fetal harm. Advise males with female partners of reproductive potential to use effective contraception during treatment and for 3 weeks after last dose. Females who are or may become pregnant should avoid handling the tablets.
• Hypoglycemia: Severe hypoglycemia reported in diabetic patients on thiazolidinediones or repaglinide. Monitor blood glucose and adjust antidiabetic treatment as needed.

Common Adverse Reactions (≥10%)

Fatigue, arthralgia, hypokalemia, hypertension, fluid retention, and liver function test abnormalities.

Serious Reactions

• Severe hepatic toxicity including fulminant hepatitis, acute liver failure, and death.
• Episodes of hypokalemia-associated QT prolongation and Torsades de Pointes (rare postmarketing reports).
• Adrenocortical insufficiency, particularly with steroid interruptions or stress.

Significant Drug Interactions

• Strong CYP3A4 Inducers (e.g., phenytoin, carbamazepine, rifampin): Avoid concomitant use or increase abiraterone acetate dosing frequency to twice daily during co-administration and resume usual dosing after discontinuation.
• Antidiabetic Agents (thiazolidinediones including pioglitazone, repaglinide): Risk of severe hypoglycemia; monitor blood glucose closely and adjust antidiabetic regimens if needed.

Pregnancy

Abiraterone acetate can cause fetal harm and pregnancy loss. Safety and efficacy have not been established in females. Animal studies showed adverse developmental effects at exposures much lower than typical human dosing.

Contraception

Males with female partners of reproductive potential should use effective contraception during treatment and for 3 weeks after the last dose.

Lactation

Information not provided.

Specific overdose information is not provided in the supplied text.

Keep abiraterone acetate tablets stored securely out of reach of females who are or may become pregnant. Specific temperature or humidity storage conditions are not provided in the supplied information.