Enzalutamide 40 mg is an oral anti-androgen medication used in the treatment of advanced prostate cancer, including metastatic castration-resistant prostate cancer (mCRPC) and non-metastatic castration-resistant prostate cancer (nmCRPC). It belongs to a class of drugs known as androgen receptor inhibitors, which work by blocking the effect of male hormones (androgens), such as testosterone, that fuel the growth of prostate cancer cells.

Enzalutamide is particularly effective because it works on multiple levels — it prevents androgens from binding to their receptors, blocks movement of the androgen-receptor complex into the cell nucleus, and inhibits interaction with DNA. This broad mechanism ultimately slows or stops the growth of hormone-driven prostate tumors.

Brand Name: Xtandi
Generic Name: Enzalutamide
Dosage Form: Oral capsule
Strength: 40 mg

Indications

Enzalutamide 40 mg is indicated for the treatment of:

• Metastatic Castration-Resistant Prostate Cancer (mCRPC)
• Non-Metastatic Castration-Resistant Prostate Cancer (nmCRPC)
• Metastatic Castration-Sensitive Prostate Cancer (mCSPC)

It is often used in combination with surgical or medical castration (use of luteinizing hormone-releasing hormone [LHRH] analogs or orchiectomy).

Mechanism of Action

Enzalutamide works by:

• Binding directly to androgen receptors
• Preventing testosterone and other androgens from activating those receptors
• Blocking translocation of the receptor to the nucleus
• Inhibiting the receptor’s ability to influence gene expression responsible for tumor growth

This triple-action inhibition makes Enzalutamide a powerful treatment option for advanced prostate cancer.

Dosage and Administration

• Typical Adult Dose: 160 mg orally once daily (administered as four 40 mg capsules)
• Route: Oral
• Administration: Can be taken with or without food
• Swallow capsules whole; do not chew, open, or dissolve

Treatment is continued until disease progression or unacceptable toxicity occurs.

Note: Patients must also receive surgical or medical castration therapy to maintain castrate levels of testosterone during treatment.

Composition

• Active Ingredient: Enzalutamide 40 mg
• Excipients: May include caprylocaproyl macrogolglycerides, butylated hydroxyanisole, gelatin, titanium dioxide, and other capsule ingredients
• Packaging: Typically packed in bottles or blister packs (30 or 120 capsules per pack)

Common Side Effects

• Fatigue
• Back pain
• Hot flashes
• Muscle pain
• Diarrhea
• High blood pressure
• Headache
• Swelling in hands or feet

Serious Side Effects

• Seizures (rare)
• Falls and fractures
• Posterior reversible encephalopathy syndrome (PRES)
• Cognitive impairment
• Hypertension-related complications

Patients require regular monitoring of blood pressure, cognitive function, and signs of neurological issues.

Warnings and Precautions

• Seizure Risk: Known to increase risk, especially in patients with prior seizure disorders
• CNS Side Effects: May worsen memory, concentration, or cause anxiety
• Pregnancy: Not for use in women; can cause harm to an unborn baby
• Reproductive Toxicity: Men using this drug should use contraception if their partner is of childbearing age

Avoid driving or operating heavy machinery if experiencing dizziness, seizures, or fatigue.

Drug Interactions

• Affected by and may affect drugs metabolized by CYP2C8 and CYP3A4 pathways
• May interact with anticoagulants, antihypertensives, and other hormone therapies
• Avoid intake of grapefruit or grapefruit juice unless approved by your doctor

Storage Conditions

• Store below 30°C (86°F)
• Keep in original packaging away from heat and moisture
• Keep out of reach of children

Do not use the capsules after the expiry date printed on the pack.