Nirogacestat is used to treat adults with desmoid tumors (a type of noncancerous tumors that occur most often in the stomach, arms, and legs) that cannot be removed by surgery. Nirogacestat is in a class of medications called gamma secretase inhibitors. It works by blocking the action of the abnormal protein that signals the tumors to grow. This helps to stop or slow tumor growth.

Nirogacestat comes as a tablet to take by mouth. It is usually taken with or without food twice a day for as long as your doctor recommends treatment. Take nirogacestat at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take nirogacestat exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the tablets whole; do not split, chew, or crush them.

If you vomit after taking nirogacestat, do not take another dose. Continue your regular dosing schedule.

Your doctor may decrease your dose of nirogacestat, treat you with other medications, or interrupt or stop your treatment if you experience certain side effects. Be sure to tell your doctor how you are feeling during your treatment with nirogacestat.

Ask your pharmacist or doctor for a copy of the manufacturer’s information for the patient.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Before taking nirogacestat,

• tell your doctor and pharmacist if you are allergic to nirogacestat, any other medications, or any of the ingredients in nirogacestat tablets. Ask your pharmacist for a list of the ingredients.
• tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• if you are taking antacids (Maalox, Mylanta, Tums); H₂ blockers such as cimetidine (Tagamet), famotidine (Pepcid), nizatidine (Axid), and ranitidine; or proton pump inhibitors such as lansoprazole (Prevacid), omeprazole (Prilosec), pantoprazole (Protonix), and rabeprazole (Aciphex), take them 2 hours before or 2 hours after nirogacestat.
• the following nonprescription or herbal product may interact with nirogacestat: St. John’s Wort. Be sure to let your doctor and pharmacist know that you are taking this medication before you start taking nirogacestat. Do not start this medication while taking nirogacestat without discussing with your healthcare provider.
• tell your doctor if you have or have ever had low levels of phosphate or potassium in the blood or liver problems.
• you should know that nirogacestat may interfere with the normal menstrual cycle (period) in women and decrease in the number of sperm (male reproductive cells) in men. However, you should not assume that you cannot get pregnant, or that you cannot get someone else pregnant. Tell your doctor if you are pregnant, plan to become pregnant, or plan to father a child. You or your partner should not become pregnant during your treatment with nirogacestat. If you are a female that can become pregnant, you will need to have a pregnancy test before you begin treatment, and you should use effective birth control during your treatment and for 1 week after your final dose. If you are a male with a female partner that can become pregnant, use effective birth control during your treatment and for 1 week after your final dose. If you or your partner become pregnant while taking nirogacestat, call your doctor. Nirogacestat may harm the fetus.
• tell your doctor if you are breast-feeding or plan to breastfeed. You should not breastfeed while you are taking nirogacestat and for 1 week after the final dose.
• you should know that this medication may decrease fertility in men and women. Talk to your doctor about the risks of taking nirogacestat.
• you should know that nirogacestat often causes diarrhea, which can be severe. Your doctor may also tell you to drink plenty of liquids, make changes in your diet, or take other medications to control the diarrhea. Call your doctor immediately if you have severe diarrhea (diarrhea that does not stop) or diarrhea that does not get better after taking an anti-diarrhea medication. Call your doctor immediately if you experience any of the following symptoms of dehydration: extreme thirst, dry mouth and/or skin, decreased urination, or fast heartbeat.

Do not eat grapefruit, starfruit, or Seville oranges (sometimes used in marmalades), or drink grapefruit juice while taking this medication.

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

Nirogacestat may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• nausea
• stomach pain
• mouth sores
• rash
• hair loss
• headache
• runny nose, nasal congestion, sneezing, or sore throat
• cough
• shortness of breath
• tiredness

Some side effects can be serious. If you experience any of these symptoms or those listed in the SPECIAL PRECAUTIONS section, call your doctor immediately:

• changes in menstrual cycle
• hot flashes
• night sweats
• vaginal dryness
• muscle pain or weakness
• new or changing skin lesions

Nirogacestat may increase the risk of developing skin cancer. Talk to your doctor about the risks of taking this medication.

Nirogacestat may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

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 light, excess heat and moisture (not in the bathroom).

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.

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can’t be awakened, immediately call emergency services at 911.

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests before and during your treatment to check your body’s response to nirogacestat.

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.

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