Enzalutamide STADA
Androgen receptor inhibitor for prostate cancer treatment
Quick Facts about Enzalutamide STADA
Key Takeaways
- Powerful androgen receptor blocker: Enzalutamide blocks androgen signalling at multiple steps, including receptor binding, nuclear translocation, and DNA interaction
- Proven survival benefit: Clinical trials (AFFIRM, PREVAIL, PROSPER, ARCHES) demonstrated significant improvements in overall and radiographic progression-free survival
- Take with or without food: 160 mg (four 40 mg tablets) once daily, swallowed whole with water
- Seizure risk: A small risk of seizures exists; patients with predisposing factors should be carefully assessed before starting treatment
- Important drug interactions: Enzalutamide is a strong CYP3A4 inducer and can reduce the effectiveness of many other medicines including blood thinners, antifungals, and certain heart medications
What Is Enzalutamide STADA and What Is It Used For?
Enzalutamide STADA is a prescription medicine containing the androgen receptor inhibitor enzalutamide (40 mg). It is used to treat prostate cancer in adult men at various stages of the disease, including metastatic castration-resistant prostate cancer (mCRPC), non-metastatic castration-resistant prostate cancer (nmCRPC), and metastatic hormone-sensitive prostate cancer (mHSPC).
Prostate cancer is the second most common cancer in men worldwide, according to the World Health Organization (WHO). Many prostate cancers are driven by androgens (male sex hormones, primarily testosterone), which bind to androgen receptors on cancer cells and stimulate their growth and division. While initial treatment often involves reducing androgen levels through medical or surgical castration, many cancers eventually develop resistance to these approaches and continue to grow even at very low androgen levels. This is known as castration-resistant prostate cancer (CRPC).
Enzalutamide STADA addresses this challenge by targeting the androgen receptor itself. Unlike older antiandrogens such as bicalutamide, enzalutamide acts at multiple points in the androgen receptor signalling pathway. It competitively inhibits the binding of androgens to the receptor, prevents the activated androgen receptor from moving into the cell nucleus (nuclear translocation), and blocks the receptor from binding to DNA to activate gene transcription. This triple mechanism of action makes enzalutamide effective even in cancer cells that have become resistant to conventional hormonal therapies.
Enzalutamide STADA is a generic version of enzalutamide, which was first authorised under the brand name Xtandi. As a generic medicine, it has demonstrated bioequivalence to the original product, meaning it delivers the same amount of active ingredient to the body and produces the same therapeutic effects. Generic medicines must meet the same rigorous quality, safety, and efficacy standards as the originator product.
Approved Indications
Enzalutamide STADA is approved by the European Medicines Agency (EMA) for the following indications in adult men:
- Metastatic castration-resistant prostate cancer (mCRPC): Cancer that has spread and continues to grow despite medical or surgical castration. Enzalutamide can be used before or after chemotherapy with docetaxel.
- Non-metastatic castration-resistant prostate cancer (nmCRPC): Cancer that has not yet spread but is at high risk of doing so, as indicated by a rapidly rising prostate-specific antigen (PSA) level despite castration.
- Metastatic hormone-sensitive prostate cancer (mHSPC): Cancer that has spread but still responds to hormonal treatment. Enzalutamide is used in combination with androgen deprivation therapy (ADT).
How Does Enzalutamide Work?
Enzalutamide belongs to a class of drugs known as androgen receptor signalling inhibitors. Its mechanism of action involves three key steps that comprehensively block androgen receptor activity:
- Blocking androgen binding: Enzalutamide binds to the ligand-binding domain of the androgen receptor with high affinity, preventing testosterone and dihydrotestosterone (DHT) from activating the receptor.
- Inhibiting nuclear translocation: Even if some receptor activation occurs, enzalutamide prevents the androgen receptor complex from moving into the cell nucleus where it would normally exert its effects.
- Preventing DNA binding: Enzalutamide inhibits the association of the activated androgen receptor with DNA, blocking the transcription of genes that promote cancer cell survival and growth.
This comprehensive blockade of the androgen receptor pathway is what distinguishes enzalutamide from first-generation antiandrogens and accounts for its superior clinical efficacy in castration-resistant settings.
What Should You Know Before Taking Enzalutamide STADA?
Before starting Enzalutamide STADA, inform your doctor about any history of seizures, heart disease, brain injuries, or stroke. This medicine should not be used by women, especially those who are or may become pregnant. It interacts significantly with many other medicines, so provide a complete list of all medications you are taking.
Contraindications
Enzalutamide STADA should not be taken if you are hypersensitive (allergic) to enzalutamide or any of the other ingredients in the tablet. This medicine is intended for use in adult men only and is not approved for use in women or children.
Enzalutamide STADA must not be handled or taken by women who are or may become pregnant. This medicine can cause harm to the developing foetus. Based on animal studies and its mechanism of action, enzalutamide may cause foetal loss and is not indicated for use in females. If a pregnant woman or a woman of childbearing potential comes into contact with leaking or broken tablets, she should wash the affected area immediately and contact her doctor.
Warnings and Precautions
Before starting treatment with Enzalutamide STADA, tell your doctor if you have or have had any of the following conditions:
- Seizures or epilepsy: Enzalutamide can lower the seizure threshold. Approximately 0.5% of patients in clinical trials experienced seizures. If you have a history of seizures, brain injury, stroke, brain tumours, alcoholism, or any other condition that may predispose you to seizures, your doctor will carefully assess the benefits and risks before prescribing this medicine.
- Heart disease: Cases of ischaemic heart disease, including fatal events, have been reported. Your doctor should monitor your cardiovascular risk factors and optimise treatment of conditions such as high blood pressure, diabetes, and high cholesterol.
- QT prolongation: Enzalutamide has been associated with QT interval prolongation on electrocardiogram (ECG). If you have a history of QT prolongation, heart failure, or electrolyte abnormalities, or if you are taking medicines known to prolong the QT interval, your doctor may need to perform ECG monitoring.
- Posterior reversible encephalopathy syndrome (PRES): Rare cases of PRES, a condition affecting the brain, have been reported. Symptoms include seizures, headache, confusion, blindness, and other visual disturbances. If any of these symptoms occur, treatment should be stopped immediately.
- Risk of falls and fractures: Falls and fractures have been reported more frequently in patients treated with enzalutamide. Your doctor should assess your risk of falls and fractures and consider bone-protective therapy where appropriate.
- Hypersensitivity reactions: Allergic reactions including swelling of the face, tongue, lip or throat have been reported. If you experience these symptoms, stop taking the medicine and seek immediate medical attention.
Pregnancy and Breastfeeding
Enzalutamide STADA is not indicated for use in women. It must not be used in women who are pregnant or who may become pregnant. Based on its mechanism of action and findings from animal reproductive studies, enzalutamide may cause harm to the developing foetus if administered during pregnancy. Men taking enzalutamide who are sexually active with women of childbearing potential should use condoms plus another effective method of contraception during treatment and for three months after the last dose.
It is not known whether enzalutamide or its metabolites are excreted in human breast milk. This medicine is not indicated for use in women, and breastfeeding women should not handle leaking or broken tablets.
Driving and Using Machines
Enzalutamide may have a moderate influence on the ability to drive and use machines. Fatigue, cognitive disturbance, dizziness, and seizures have been reported in patients taking enzalutamide. Patients should be advised of the potential risk of these effects and counselled not to drive or operate hazardous machinery if they experience these symptoms. If a seizure occurs, the patient should permanently discontinue enzalutamide and should not drive or use machines until the treating physician confirms it is safe to do so.
How Does Enzalutamide STADA Interact with Other Drugs?
Enzalutamide is a strong inducer of CYP3A4 and a moderate inducer of CYP2C9 and CYP2C19 enzymes, meaning it can significantly reduce the blood levels and effectiveness of many other medications. Conversely, strong CYP2C8 inhibitors can increase enzalutamide levels. Always tell your doctor about all medicines you are taking.
Drug interactions are a critical concern with enzalutamide because it significantly affects the liver enzymes (cytochrome P450 system) responsible for metabolising many common medications. Enzalutamide is primarily metabolised by CYP2C8 and, to a lesser extent, CYP3A4. More importantly, enzalutamide is a potent inducer of several CYP enzymes, which means it accelerates the breakdown of other drugs in the body, potentially rendering them ineffective.
Your doctor and pharmacist will review your complete medication list before starting enzalutamide. In some cases, alternative medications may be necessary, or dose adjustments may be required. Never stop, start, or change the dose of any medicine without first consulting your doctor.
Major Interactions
| Drug / Drug Class | Effect of Interaction | Clinical Action |
|---|---|---|
| Warfarin (blood thinner) | Reduced warfarin levels due to CYP2C9 induction; risk of therapeutic failure and blood clots | Avoid if possible; if co-administration necessary, monitor INR closely and adjust warfarin dose |
| Midazolam (sedative) | Reduced midazolam AUC by up to 86%; may result in lack of sedative effect | Avoid CYP3A4 substrates with narrow therapeutic index; consider alternative sedatives |
| Omeprazole (acid reflux) | Reduced omeprazole exposure due to CYP2C19 induction; may reduce acid suppression | Consider alternative acid-reducing medications or increase dose; monitor symptom control |
| Gemfibrozil (cholesterol) | Strong CYP2C8 inhibitor increases enzalutamide AUC by approximately 2.2-fold | Avoid co-administration; if unavoidable, reduce enzalutamide dose to 80 mg once daily |
| Itraconazole (antifungal) | Strong CYP3A4 inhibitor may increase enzalutamide levels; however, CYP3A4 plays minor role | No dose adjustment needed for CYP3A4 inhibitors alone; monitor for increased side effects |
| Carbamazepine / Phenytoin (anti-seizure) | Strong CYP3A4 inducers may decrease enzalutamide levels | Avoid concomitant use of strong CYP3A4 inducers; select alternative anti-seizure medicines |
| Dabigatran (blood thinner) | Enzalutamide may induce P-glycoprotein and reduce dabigatran levels | Use with caution; monitor for reduced anticoagulant effect |
Minor Interactions
Enzalutamide may also interact with substrates of CYP2B6 (such as bupropion and efavirenz) and UGT1A1 (such as levothyroxine). While these interactions may be less clinically significant, dose adjustments or monitoring may still be required. Inform your doctor of all prescription and non-prescription medicines, vitamins, and herbal supplements you take.
St John's wort (Hypericum perforatum) is a strong CYP3A4 inducer that may reduce enzalutamide blood levels. Avoid using herbal products containing St John's wort while taking enzalutamide. Always inform your doctor about any herbal remedies or dietary supplements you are using.
What Is the Correct Dosage of Enzalutamide STADA?
The recommended dose of Enzalutamide STADA is 160 mg (four 40 mg tablets) taken orally once daily, with or without food. The tablets should be swallowed whole with water. Treatment continues until disease progression or unacceptable toxicity. Medical or surgical castration therapy should be continued concurrently unless the patient has had a bilateral orchiectomy.
Adults
Standard Adult Dosage
Dose: 160 mg (four 40 mg film-coated tablets) once daily
Administration: Oral, with or without food
Instructions: Swallow tablets whole with water. Do not crush, break, or chew the tablets.
Duration: Continue treatment until disease progression, unacceptable toxicity, or physician decision to discontinue
Concurrent therapy: Medical castration with a GnRH agonist or antagonist should be continued during enzalutamide treatment, unless the patient has had a bilateral orchiectomy.
If you experience certain side effects, your doctor may reduce your dose to 120 mg (three tablets) or 80 mg (two tablets) once daily. Dose adjustments may be necessary in the following situations:
- Grade 3 or higher toxicity: Treatment may be interrupted until the side effect improves, then resumed at the same or a reduced dose
- Co-administration with strong CYP2C8 inhibitors (e.g., gemfibrozil): Reduce the dose to 80 mg once daily
- Seizures: Enzalutamide should be permanently discontinued if a seizure occurs during treatment
Children
Enzalutamide STADA is not indicated for use in children or adolescents. The safety and efficacy of enzalutamide in the paediatric population have not been established. There is no relevant use of enzalutamide in children for the approved indication of prostate cancer.
Elderly
No dose adjustment is necessary for elderly patients. Clinical trials included a substantial proportion of patients aged 75 years and older, and no overall differences in safety or efficacy were observed between these patients and younger patients. However, elderly patients may be more susceptible to certain side effects, particularly falls, fractures, cognitive changes, and fatigue, and should be monitored accordingly.
Patients with Renal or Hepatic Impairment
No dose adjustment is required for patients with mild to moderate renal impairment (creatinine clearance ≥ 30 mL/min) or mild hepatic impairment (Child-Pugh A). Caution is advised in patients with severe renal impairment or moderate hepatic impairment (Child-Pugh B). Enzalutamide has not been studied in patients with severe hepatic impairment (Child-Pugh C) and is therefore not recommended in this population.
Missed Dose
If you forget to take your daily dose of Enzalutamide STADA, take it as soon as you remember on the same day. If you miss a dose for an entire day, simply take your normal dose the following day. Do not take a double dose to make up for a missed dose. If you frequently forget to take your medicine, tell your doctor.
Overdose
There is no specific antidote for enzalutamide overdose. In the event of an overdose, stop taking enzalutamide and contact your doctor or go to an emergency department immediately. In clinical trials, limited experience with doses above 240 mg per day suggested an increased risk of seizures at higher doses. Treatment of overdose is supportive and symptomatic, with particular attention to the risk of seizures.
What Are the Side Effects of Enzalutamide STADA?
The most common side effects of enzalutamide include fatigue, hot flushes, hypertension, falls, and fractures. Serious but less common side effects include seizures, posterior reversible encephalopathy syndrome (PRES), ischaemic heart disease, and QT prolongation. Most side effects are manageable with dose modification or supportive care.
Like all medicines, Enzalutamide STADA can cause side effects, although not everybody gets them. The side effects listed below are based on data from pivotal clinical trials involving thousands of patients and post-marketing surveillance reports. If you experience any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed below.
Very Common
- Fatigue and asthenia (tiredness and weakness)
- Hot flushes
- Hypertension (high blood pressure)
- Falls
- Fractures (broken bones)
- Headache
Common
- Anxiety
- Cognitive disorder (difficulty thinking, concentrating, or remembering)
- Memory impairment
- Dizziness
- Restless legs syndrome
- Dry skin and pruritus (itching)
- Muscle weakness and musculoskeletal pain
- Gynaecomastia (breast enlargement)
- Weight decreased
- Decreased white blood cell count (neutropenia)
- Diarrhoea and nausea
Uncommon
- Seizures (approximately 0.5% of patients)
- Ischaemic heart disease (including myocardial infarction)
- QT prolongation on ECG
- Visual hallucinations
- Leukopenia (low white blood cell count)
Rare
- Posterior reversible encephalopathy syndrome (PRES)
- Severe hypersensitivity reactions (angioedema, tongue swelling)
- Stevens-Johnson syndrome / toxic epidermal necrolysis
- Myasthenia gravis (muscle weakness disorder)
Contact your doctor or go to an emergency department immediately if you experience any of the following:
- A seizure (convulsion or fit)
- Sudden severe headache with confusion, visual disturbances, or blindness (possible signs of PRES)
- Chest pain, shortness of breath, or symptoms of a heart attack
- Swelling of the face, tongue, lips, or throat (signs of severe allergic reaction)
- Severe skin reactions with blistering or peeling
The most common reason for dose reduction or treatment interruption in clinical trials was fatigue, followed by hypertension and falls. Most side effects improved with temporary dose interruption, dose reduction, or supportive care. Your doctor will weigh the benefits of continued treatment against any side effects you experience.
Reporting Side Effects
If you get any side effects, talk to your doctor or pharmacist. You can also report side effects directly to your national medicines regulatory authority. By reporting side effects, you can help provide more information on the safety of this medicine.
How Should You Store Enzalutamide STADA?
Store Enzalutamide STADA below 30°C in the original packaging. Keep out of the sight and reach of children. Do not use the medicine after the expiry date stated on the carton and blister packaging.
Proper storage of Enzalutamide STADA is essential to maintain the quality and effectiveness of the medicine. Follow these storage guidelines:
- Temperature: Store below 30°C. No special temperature requirements such as refrigeration are needed.
- Packaging: Keep the tablets in the original blister packaging to protect from moisture.
- Children: Keep this medicine out of the sight and reach of children.
- Expiry date: Do not use Enzalutamide STADA after the expiry date printed on the carton and blister. The expiry date refers to the last day of that month.
- Disposal: Do not throw away medicines via household waste or wastewater. Ask your pharmacist how to dispose of medicines you no longer use. These measures help to protect the environment.
If a tablet is broken or damaged, do not handle it with bare hands, especially if you are a woman who is pregnant or may become pregnant. Contact with damaged tablets should be avoided due to the risk of absorption through the skin.
What Does Enzalutamide STADA Contain?
Each Enzalutamide STADA 40 mg film-coated tablet contains 40 mg of enzalutamide as the active substance. The tablets also contain inactive excipients necessary for manufacturing and stability.
Understanding the full composition of your medicine can be important, particularly if you have known allergies or intolerances to specific pharmaceutical excipients.
Active Substance
Each film-coated tablet contains 40 mg of enzalutamide. Enzalutamide is the active substance responsible for the therapeutic effect. Its chemical name is 4-{3-[4-cyano-3-(trifluoromethyl)phenyl]-5,5-dimethyl-4-oxo-2-thioxoimidazolidin-1-yl}-2-fluoro-N-methylbenzamide, with the molecular formula C21H16F4N4O2S and a molecular weight of 464.44 g/mol.
Excipients (Inactive Ingredients)
The other ingredients in Enzalutamide STADA 40 mg film-coated tablets include:
- Tablet core: Hypromellose acetate succinate, microcrystalline cellulose, silica colloidal anhydrous, croscarmellose sodium, magnesium stearate, sodium laurilsulfate
- Film coating: Hypromellose, iron oxide yellow (E172), titanium dioxide (E171), macrogol, talc
The film-coated tablets are round, yellow, and marked with the strength on one side. If you are allergic to any of the listed excipients, consult your doctor or pharmacist before taking this medicine.
Frequently Asked Questions
References
- European Medicines Agency (EMA). Xtandi (enzalutamide) - Summary of Product Characteristics. Last updated 2024. Available at: ema.europa.eu/en/medicines/human/EPAR/xtandi
- U.S. Food and Drug Administration (FDA). XTANDI (enzalutamide) Prescribing Information. Revised 2023. Available at: accessdata.fda.gov
- Scher HI, Fizazi K, Saad F, et al. Increased survival with enzalutamide in prostate cancer after chemotherapy. N Engl J Med. 2012;367(13):1187-1197. doi:10.1056/NEJMoa1207506 (AFFIRM trial)
- Beer TM, Armstrong AJ, Rathkopf DE, et al. Enzalutamide in metastatic prostate cancer before chemotherapy. N Engl J Med. 2014;371(5):424-433. doi:10.1056/NEJMoa1405095 (PREVAIL trial)
- Hussain M, Fizazi K, Saad F, et al. Enzalutamide in men with nonmetastatic, castration-resistant prostate cancer. N Engl J Med. 2018;378(26):2465-2474. doi:10.1056/NEJMoa1800536 (PROSPER trial)
- Armstrong AJ, Szmulewitz RZ, Petrylak DP, et al. ARCHES: a randomized, phase III study of androgen deprivation therapy with enzalutamide or placebo in men with metastatic hormone-sensitive prostate cancer. J Clin Oncol. 2019;37(32):2974-2986. doi:10.1200/JCO.19.00799
- National Comprehensive Cancer Network (NCCN). Clinical Practice Guidelines in Oncology: Prostate Cancer. Version 4.2024.
- Parker C, Castro E, Fizazi K, et al. Prostate cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Ann Oncol. 2020;31(9):1119-1134. doi:10.1016/j.annonc.2020.06.011
- World Health Organization (WHO). Model List of Essential Medicines - 23rd List, 2023. Geneva: World Health Organization.
- British National Formulary (BNF). Enzalutamide. National Institute for Health and Care Excellence (NICE). Available at: bnf.nice.org.uk
Editorial Team
This article was written and reviewed by iMedic's medical editorial team, consisting of licensed physicians specialising in oncology, urology, and clinical pharmacology.
iMedic Medical Editorial Team
Specialists in oncology and pharmacology
iMedic Medical Review Board
Independent panel of medical experts
Level 1A (systematic reviews, RCTs)
GRADE evidence framework
EMA, FDA, NCCN, ESMO, WHO
International medical standards
Last reviewed: . This information is regularly updated in accordance with current medical guidelines and evidence. iMedic receives no commercial funding. All content is independent and evidence-based.