Pexidartinib may cause serious or life threatening liver damage. Tell your doctor if you have or ever have had liver disease. Tell your doctor and pharmacist about the medications you are taking so they can check whether any of your medications may increase the risk that you will develop liver damage during your treatment with pexidartinib. If you experience any of the following symptoms, call your doctor immediately: extreme tiredness, loss of appetite, weight loss, nausea, vomiting, unusual bleeding or bruising, yellowing of the skin or eyes, dark yellow or brown-colored urine, pale stools, or pain in the upper right part of the stomach. Your doctor may have to decrease your dose of pexidartinib or permanently or temporarily stop your treatment.

A program called Turalio Risk Evaluation and Mitigation Strategy (REMS) has been set up to manage the risks of this medication. You will only be able to receive pexidartinib if you and the doctor who prescribes your medication is enrolled are the program. You can only receive the medication from a pharmacy that participates in the program. Ask your doctor if you have any questions about participating in the program or how to get your medication.

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests before and during your treatment to be sure that it is safe for you to take pexidartinib and to check your body’s response to the medication.

Your doctor or pharmacist will give you the manufacturer’s patient information sheet (Medication Guide) when you begin treatment with pexidartinib and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website (http://www.fda.gov/Drugs/DrugSafety/ucm085729.htm) or the manufacturer’s website to obtain the Medication Guide.

Talk to your doctor about the risks of taking pexidartinib.

Pexidartinib is used to treat tenosynovial giant cell tumors (TGCT; tumors in or around a joint that can cause pain, swelling, and reduce movement) in adults that cannot be treated by surgery. Pexidartinib is in a class of medications called kinase inhibitors. It works by blocking the action of an abnormal protein that may help the tumor to shrink.

Pexidartinib comes as a capsule to take by mouth. It is usually taken twice daily on an empty stomach at least 1 hour before or 2 hours after a meal or snack. Take pexidartinib at around the same time(s) 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 pexidartinib exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the capsules whole; do not open, chew, or crush them.

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

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

Before taking pexidartinib,

• Tell your doctor and pharmacist if you are allergic to pexidartinib, any other medications, or any of the ingredients in pexidartinib capsules. Ask your pharmacist or check the Medication Guide 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. Be sure to mention any of the following: clarithromycin (Biaxin, in Prevpac); certain antifungals such as itraconazole (Onmel, Sporanox) or ketoconazole; enzalutamide (Xtandi); certain medications for human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS) such as efavirenz (Sustiva, in Atripla), indinavir (Crixivan), nelfinavir (Viracept), nevirapine (Viramune), ritonavir (Norvir, in Kaletra), and saquinavir (Invirase); modafinil (Provigil); nefazodone; pioglitazone (Actos, in Duetact, Oseni); probenecid (Probalan); proton-pump inhibitors such as esomeprazole (Nexium), lansoprazole (Prevacid), omeprazole (Prilosec), pantoprazole (Protonix), and rabeprazole (AcipHex); rifabutin (Mycobutin); rifampin (Rifadin); certain medications for seizures such as carbamazepine (Equetro, Tegretol, Teril), phenobarbital, and phenytoin (Dilantin, Phenytek); or oral steroids such as dexamethasone, methylprednisolone (Medrol), and prednisone. Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with pexidartinib, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
• If you are taking antacids containing magnesium or aluminum (Maalox, Mylanta, Tums, others), take the antacid 2 hours before or at least 2 hours after you take pexidartinib.
• If you are taking a medication for indigestion, heartburn, or ulcers such as cimetidine (Tagamet), famotidine (Pepcid, in Duexis), nizatidine (Axid), or ranitidine (Zantac), take it at least 10 hours before or at least 2 hours after you take pexidartinib.
• Tell your doctor and pharmacist what herbal products you are taking, especially St. John’s wort. You should not take St. John’s wort during your treatment with pexidartinib.
• Tell your doctor if you have or have ever had kidney disease.
• Tell your doctor if you are pregnant, plan to become pregnant, or if you plan on fathering a child. If you are female, you will need to take a pregnancy test before you start treatment and use birth control to prevent pregnancy during your treatment and for 1 month after your final dose. If you are a male, you and your partner should use birth control during your treatment with pexidartinib and for 1 week after your final dose. Talk to your doctor about birth control methods that you can use during your treatment. Pexidartinib may decrease fertility in men and women. However, you should not assume that you or your partner cannot become pregnant. If you or your partner become pregnant while taking pexidartinib, call your doctor immediately. Pexidartinib may harm the fetus.
• Tell your doctor if you are breastfeeding. You should not breastfeed while you are taking pexidartinib and for 1 week after your final dose.

Do not eat large amounts of grapefruit or drink grapefruit juice while taking this medication.

Skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

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

• Hair color changes
• Changes in taste
• Tiredness
• Constipation

Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately or get emergency medical treatment:

• Rash
• Itching
• Swelling of the hands, feet, legs or ankles
• Pain in arms or legs
• Swelling in or around the eye

Pexidartinib 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 excess heat and moisture (not in the bathroom). Do not remove the desiccant (small packet included with medication to absorb moisture) from the bottle, if one has been provided.

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.

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.