Airuiji Abiraterone Acetate Tablets (II)

1. Indications and Usage
According to the National Medical Products Administration drug registration information, the drug is indicated for the treatment of metastatic castration-resistant prostate cancer (mCRPC) and metastatic high-risk hormone-sensitive prostate cancer (mHSPC).
2. Dosage and Administration
Recommended Dosage: The recommended dosage is 1000 mg (4x250mg tablets) taken orally once daily.
Combination Therapy: It must be used in combination with prednisone or prednisolone.
Administration: It must be taken on an empty stomach (at least 1 hour before or 2 hours after a meal) and swallowed whole.
3. Mechanism of Action
Abiraterone acetate is a prodrug that is hydrolyzed by esterases to abiraterone, which selectively and irreversibly inhibits CYP17A1 (CYP17). This blockade prevents the synthesis of androgens (such as testosterone) from precursors in the testes, adrenals, and within the tumor itself.
4. Safety and Warnings
Hepatotoxicity: Transaminase elevations and hepatocellular injury have been reported. Liver function tests should be monitored before initiation, every 2 weeks for the first 3 months, and then monthly thereafter.
Mineralocorticoid Excess: Inhibition of CYP17 can lead to increased corticosterone, causing hypertension, hypokalemia, and fluid retention.
Fetal Toxicity: The drug can cause fetal harm and is contraindicated in pregnant women.
5. Adverse Reactions and Clinical Research
Adverse Reactions: The most common adverse reactions include peripheral edema, hypokalemia, hypertension, and urinary tract infections.
Clinical Research: Clinical trials have demonstrated that abiraterone acetate significantly prolongs overall survival and delays radiographic progression in patients with mCRPC.
6. Drug Interactions
CYP3A4 Inducers: Strong CYP3A4 inducers (e.g., rifampin) significantly decrease abiraterone exposure and should be avoided.
CYP2D6 Substrates: Abiraterone inhibits CYP2D6; caution is required when co-administering narrow therapeutic index substrates of CYP2D6.
7. Pharmaceutical Information
Composition: The active ingredient is abiraterone acetate.
Appearance: The tablets are white or off-white.
Storage: The tablets should be stored at controlled room temperature and protected from moisture.