Relugolix is a prescription medicine used to treat advanced prostate cancer (cancer that begins in the prostate [a male reproductive gland]) in adult men. Relugolix belongs to a class of medications called gonadotropin-releasing hormone (GnRH) receptor antagonists.

Relugolix tablets work by decreasing the amount of testosterone (a male hormone) produced by the body. This may slow or stop the spread of prostate cancer cells that need testosterone to grow.

Relugolix may decrease fertility in men. Talk to your doctor about the risks.

Relugolix is intended only for use in men. This medicine is not intended for use alone in women, but can be used in combination with other medications for other uses. If you are a male and your female partner can become pregnant, you should use effective contraception during treatment and for 2 weeks after the last dose. Relugolix may harm the fetus.

Tell your doctor if you or anyone in your family has or has ever had long QT syndrome (a rare heart problem that may cause irregular heartbeat, fainting, or sudden death). Also, tell your doctor if you have or have ever had an electrolyte imbalance in your blood, heart failure, diabetes, high triglycerides (fatty substances in the blood), anemia, or liver problems.

Tell your doctor and pharmacist if you are allergic to relugolix, any other medications, or any of the ingredients in the tablets. Ask your pharmacist for a list of the ingredients.

Before taking this medicine

You should not use relugolix if you are allergic to it, or if you have:

• heart problems; or

• long QT syndrome (in you or a family member).

Relugolix can harm an unborn baby and cause loss of pregnancy (miscarriage).

• If you are a man, use birth control if your sex partner is able to get pregnant. Keep using birth control for at least 2 weeks after your last dose.

• Tell your doctor if your partner is pregnant or plans to get pregnant.

It may be harder for you to get a woman pregnant while you are using this medicine. You should still use birth control to prevent pregnancy because the medicine can harm an unborn baby.

Take relugolix tablets exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose.

Relugolix is usually taken as 3 tablets the first day, followed by 1 tablet per day.

Take the medicine at the same time each day, with or without food.

Swallow the tablet whole and do not crush, chew, or break it.

You will need frequent medical tests. Your heart function may need to be checked using an electrocardiogram or ECG (sometimes called an EKG).

Your doctor will determine how long to treat you with relugolix. Do not change your dose or stop using this medicine without your doctor's advice.

Store tightly closed at room temperature, away from moisture and heat. Keep the tablets in their original container, along with the packet or canister of moisture-absorbing preservative.

Do not keep leftover medicine. Ask your pharmacist about a drug take-back program. You may also mix the leftover medicine with cat litter or coffee grounds in a sealed plastic bag and throw the bag in the trash. Do not flush down the toilet.

Usual Adult Dose for Prostate Cancer:

Loading Dose: 300 mg orally once on the first day
Maintenance Dose: 120 mg orally once a day

Comment:
-Treatment is usually continued upon development of nonmetastatic or metastatic castration-resistant prostate cancer in patients treated with GnRH receptor agonists and antagonists.

Use: For the treatment of adult patients with advanced prostate cancer

You should not use relugolix if you are allergic to it, or if you have:

• heart problems; or

• long QT syndrome (in you or a family member).

Relugolix can harm an unborn baby and cause loss of pregnancy (miscarriage).

• If you are a man, use birth control if your sex partner is able to get pregnant. Keep using birth control for at least 2 weeks after your last dose.

• Tell your doctor if your partner is pregnant or plans to get pregnant.

It may be harder for you to get a woman pregnant while you are using this medicine. You should still use birth control to prevent pregnancy because the medicine can harm an unborn baby.

Use the medicine as soon as you can, but skip the missed dose if you are more than 12 hours late for the dose. Do not use two doses at one time.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Do not remove the desiccant (small packet included with medication to absorb moisture).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

Unless your doctor tells you otherwise, continue your normal diet.

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Get emergency medical help if you have signs of an allergic reaction to relugolix: hives, difficult breathing, swelling of your face, lips, tongue, or throat, trouble swallowing.

Relugolix may cause serious side effects. Call your doctor at once if you have:

• fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness (like you might pass out);

• chest pain or pressure;

• sudden numbness or weakness on one side of the body;

• little or no urination, pain or burning when you urinate; or

• unusual bleeding.

Common relugolix side effects may include:

• flushing (sudden warmth, redness, or tingly feeling);

• feeling tired;

• high blood sugar;

• high cholesterol or triglycerides;

• (anemia) low red blood cells;

• depressed mood;

• weight gain;

• impotence, sexual problems;

• abnormal growth of breast tissue;

• diarrhea, constipation;

• muscle or joint pain; or

• abnormal lab tests (liver, blood).

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Sometimes it is not safe to use certain medicines at the same time. Some drugs can affect your blood levels of other drugs you use, which may increase side effects or make the medicines less effective.

Relugolix can cause a serious heart problem. Your risk may be higher if you also use certain other medicines for infections, asthma, heart problems, high blood pressure, depression, mental illness, cancer, malaria, or HIV.

Certain other drugs should not be used within 6 hours after you take relugolix. Your dose should be taken first, before other medicines. Carefully follow your doctor's instructions about how to schedule the doses of all your medicines.

Many drugs can interact with relugolix. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell your doctor about all other medicines you use.

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response to relugolix.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are taking relugolix.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.