• Keep this leaflet. You may need to read it again.
• If you have any further questions, ask your doctor.
• This medicine has been prescribed for you only. Do not pass it on to others. It may harm them, even if their signs of illness are the same as yours.
• If you get any side effects, talk to your doctor. This includes any possible side effects not listed in this leaflet. See section 4.

1. What Xtandi is and what it is used for
2. What you need to know before you take Xtandi
3. How to take Xtandi
4. Possible side effects
5. How to store Xtandi
6. Contents of the pack and other information

Xtandi is a medicine that works by blocking the activity of hormones called androgens (such as testosterone). By blocking androgens, enzalutamide stops prostate cancer cells from growing and dividing.

• If you are allergic to enzalutamide or any of the other ingredients of this medicine (listed in section 6)
• If you are pregnant or may become pregnant (see ‘Pregnancy, breast-feeding and fertility’)

Seizures

Seizures were reported in 6 in every 1,000 people taking Xtandi, and fewer than 3 in every 1,000 people taking placebo (see ‘Other medicines and Xtandi’ below and section 4 ‘Possible side effects’).

If you are taking a medicine that can cause seizures or that can increase the susceptibility for having seizures (see ‘Other medicines and Xtandi’ below).

If you have a seizure during treatment:

See your doctor as soon as possible. Your doctor may decide that you should stop taking Xtandi.

Posterior reversible encephalopathy syndrome (PRES)

There have been rare reports of PRES, a rare, reversible condition involving the brain, in patients treated with Xtandi. If you have a seizure, worsening headache, confusion, blindness or other vision problems, please contact your doctor as soon as possible. (See also section 4 ‘Possible side effects’).

Risk of new cancers (second primary malignancies)

There have been reports of new (second) cancers including cancer of the bladder and colon in patients treated with Xtandi.

See your doctor as soon as possible if you notice signs of gastrointestinal bleeding, blood in the urine, or frequently feel an urgent need to urinate when taking Xtandi.

Talk to your doctor before taking Xtandi

• If you have ever developed a severe skin rash or skin peeling, blistering and/or mouth sores after taking Xtandi or other medicines
• If you are taking any medicines to prevent blood clots (e.g. warfarin, acenocoumarol, clopidogrel)
• If you use chemotherapy like docetaxel
• If you have problems with your liver
• If you have problems with your kidneys

Please tell your doctor if you have any of the following:

Any heart or blood vessel conditions, including heart rhythm problems (arrhythmia), or are being treated with medicines for these conditions. The risk of heart rhythm problems may be increased when using Xtandi.

If you are allergic to enzalutamide, this may result in a rash or swelling of the face, tongue, lip or throat. If you are allergic to enzalutamide or any of the other ingredients of this medicine, do not take Xtandi.

Serious skin rash or skin peeling, blistering and/or mouth sores, including Stevens-Johnson syndrome, have been reported in association with Xtandi treatment. Stop using Xtandi and seek medical attention immediately if you notice any of the symptoms related to these serious skin reactions described in section 4.

If any of the above applies to you or you are not sure, talk to your doctor before taking this medicine.

This medicine is not for use in children and adolescents.

Tell your doctor if you are taking, have recently taken or might take any other medicines. You need to know the names of the medicines you take. Keep a list of them with you to show to your doctor when you are prescribed a new medicine. You should not start or stop taking any medicine before you talk with the doctor that prescribed Xtandi.

Tell your doctor if you are taking any of the following medicines. When taken at the same time as Xtandi, these medicines may increase the risk of a seizure:

• Certain medicines used to treat asthma and other respiratory diseases (e.g. aminophylline, theophylline).
• Medicines used to treat certain psychiatric disorders such as depression and schizophrenia (e.g. clozapine, olanzapine, risperidone, ziprasidone, bupropion, lithium, chlorpromazine, mesoridazine, thioridazine, amitriptyline, desipramine, doxepin, imipramine, maprotiline, mirtazapine).
• Certain medicines for the treatment of pain (e.g. pethidine).

Tell your doctor if you are taking the following medicines. These medicines may influence the effect of Xtandi, or Xtandi may influence the effect of these medicines.

This includes certain medicines used to:

• Lower cholesterol (e.g. gemfibrozil, atorvastatin, simvastatin)
• Treat pain (e.g. fentanyl, tramadol)
• Treat cancer (e.g. cabazitaxel)
• Treat epilepsy (e.g. carbamazepine, clonazepam, phenytoin, primidone, valproic acid)
• Treat certain psychiatric disorders such as severe anxiety or schizophrenia (e.g. diazepam, midazolam, haloperidol)
• Treat sleep disorders (e.g. zolpidem)
• Treat heart conditions or lower blood pressure (e.g. bisoprolol, digoxin, diltiazem, felodipine, nicardipine, nifedipine, propranolol, verapamil)
• Treat serious disease related to inflammation (e.g. dexamethasone, prednisolone)
• Treat HIV infection (e.g. indinavir, ritonavir)
• Treat bacterial infections (e.g. clarithromycin, doxycycline)
• Treat thyroid disorders (e.g. levothyroxine)
• Treat gout (e.g. colchicine)
• Treat stomach disorders (e.g. omeprazole)
• Prevent heart conditions or strokes (e.g. dabigatran etexilate)
• Prevent organ rejection (e.g. tacrolimus)

Xtandi might interfere with some medicines used to treat heart rhythm problems (e.g. quinidine, procainamide, amiodarone and sotalol) or might increase the risk of heart rhythm problems when used with some other medicines [e.g. methadone (used for pain relief and part of drug addiction detoxification), moxifloxacin (an antibiotic), antipsychotics (used for serious mental illnesses)].

Tell your doctor if you are taking any of the medicines listed above. The dose of Xtandi or any other medicines that you are taking may need to be changed.

• Xtandi is not for use in women. This medicine may cause harm to the unborn child or potential loss of pregnancy if taken by women who are pregnant. It must not be taken by women who are pregnant, may become pregnant, or who are breast-feeding.
• This medicine could possibly have an effect on male fertility.
• If you are having sex with a woman who can become pregnant, use a condom and another effective birth control method, during treatment and for 3 months after treatment with this medicine. If you are having sex with a pregnant woman, use a condom to protect the unborn child.
• Female caregivers see section 3 ‘How to take Xtandi’ for handling and use.

Xtandi may have moderate influence on the ability to drive and use machines. Seizures have been reported in patients taking Xtandi. If you are at higher risk of seizures, talk to your doctor.

This medicine contains less than 1 mmol sodium (less than 23 mg) per film-coated tablet, that is to say essentially ‘sodium-free’.

• Swallow the tablets whole with water.
• Do not cut, crush or chew the tablets before swallowing.
• Xtandi can be taken with or without food.
• Xtandi should not be handled by persons other than the patient or his caregivers. Women who are or may become pregnant should not handle broken or damaged Xtandi tablets without wearing protection like gloves.

Your doctor may also prescribe other medicines while you are taking Xtandi.

If you take more tablets than prescribed, stop taking Xtandi and contact your doctor. You may have an increased risk of seizure or other side effects.

• If you forget to take Xtandi at the usual time, take your usual dose as soon as you remember.
• If you forget to take Xtandi for the whole day, take your usual dose the following day.
• If you forget to take Xtandi for more than one day, talk to your doctor immediately.
• Do not take a double dose to make up for the dose you forgot.

Do not stop taking this medicine unless your doctor tells you to.

Seizures were reported in 6 in every 1,000 people taking Xtandi, and in fewer than 3 in every 1,000 people taking placebo.

Seizures are more likely if you take more than the recommended dose of this medicine, if you take certain other medicines, or if you are at higher than usual risk of seizure.

If you have a seizure, see your doctor as soon as possible. Your doctor may decide that you should stop taking Xtandi.

There have been rare reports of PRES (may affect up to 1 in 1,000 people), a rare, reversible condition involving the brain, in patients treated with Xtandi. If you have a seizure, worsening headache, confusion, blindness or other vision problems, please contact your doctor as soon as possible.

Very common (may affect more than 1 in 10 people)

Tiredness, fall, broken bones, hot flushes, high blood pressure

Common (may affect up to 1 in 10 people)

Headache, feeling anxious, dry skin, itching, difficulty remembering, blockage of the arteries in the heart (ischemic heart disease), breast enlargement in men (gynaecomastia), nipple pain, breast tenderness, symptom of restless legs syndrome (an uncontrollable urge to move a part of the body, usually the leg), reduced concentration, forgetfulness, change in sense of taste, difficulty thinking clearly

Uncommon (may affect up to 1 in 100 people)

Hallucinations, low white blood cell count, increased liver enzyme levels in blood test (a sign of liver problems)

Not known (frequency cannot be estimated from the available data)

Muscle pain, muscle spasms, muscular weakness, back pain, changes in ECG (QT prolongation), upset stomach including feeling sick (nausea), a skin reaction that causes red spots or patches on the skin that may look like a target or “bulls-eye” with a dark red centre surrounded by paler red rings (erythema multiforme), or another serious skin reaction presenting reddish non-elevated, target-like or circular patches on the trunk, often with central blisters, skin peeling, ulcers of mouth, throat, nose, genitals and eyes that can be preceded by fever and flu-like symptoms (Stevens-Johnson syndrome), rash, being sick (vomiting), swelling of the face, lips, tongue and/or throat, reduction in blood platelets (which increases risk of bleeding or bruising), diarrhoea

If you get any side effects, talk to your doctor. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store. By reporting side effects you can help provide more information on the safety of this medicine.

The active substance is enzalutamide.

Each Xtandi 40 mg film-coated tablet contains 40 mg of enzalutamide.

The other ingredients of the film-coated tablets are:

• Tablet core: Hypromellose acetate succinate, microcrystalline cellulose, colloidal anhydrous silica, croscarmellose sodium, magnesium stearate.
• Tablet coating: Hypromellose, talc, macrogol 8000, titanium dioxide (E171), yellow iron oxide (E172).

Xtandi 40 mg film-coated tablets are yellow round film-coated tablets, debossed with E 40. Each carton contains 112 tablets in 4 blister wallets of 28 tablets each.