Olutasidenib may cause a serious or life-threatening group of symptoms called differentiation syndrome. Your doctor will monitor you carefully to see whether you are developing this syndrome. If you experience any of the following symptoms, call your doctor immediately: fever, cough, rash, sudden weight gain, decreased urination, swelling of arms or legs, dizziness or lightheadedness, shortness of breath, or difficulty breathing. These symptoms may occur up to 18 months after starting treatment with olutasidenib.

At the first sign that you are developing differentiation syndrome, your doctor will prescribe medications to treat the syndrome, and may tell you to stop taking olutasidenib for some time. Keep all appointments with your doctor and the laboratory. Your doctor will order certain tests before and during your treatment to check your body’s response to olutasidenib.

Your doctor or pharmacist will give you the manufacturer’s patient information sheet (Medication Guide) when you begin treatment with olutasidenib 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 ) to obtain the Medication Guide.

Olutasidenib is used to treat a certain type of acute myeloid leukemia (AML; a type of cancer that begins in the white blood cells) that has returned or that has not improved after previous treatment(s). Olutasidenib is in a class of medications called IDH1 inhibitors. It works by slowing or stopping the growth of cancer cells.

Olutasidenib comes as a capsule to take by mouth. It is usually taken 2 times a day, at least 8 hours apart. Olutasidenib should be taken 1 hour before or 2 hours after a meal. Take olutasidenib 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 olutasidenib 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 split, chew, or crush them.

Your doctor may reduce your dose or temporarily or permanently stop your treatment with olutasidenib depending on your response to treatment or any side effects that you experience. Talk to your doctor about how you are feeling during your treatment. Do not stop taking olutasidenib without talking to your doctor first.

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

Before taking olutasidenib,

• tell your doctor and pharmacist if you are allergic to olutasidenib, any other medications, or any of the ingredients in olutasidenib capsules. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take while taking olutasidenib. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• The following nonprescription or herbal products may interact with olutasidenib: St. John’s Wort. Be sure to let your doctor and pharmacist know that you are taking this medications before you start taking olutasidenib. Do not start taking this herbal medication while taking olutasidenib without discussing with your healthcare provider.
• tell your doctor if you have or have ever had liver or kidney disease.
• tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking olutasidenib, call your doctor.

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

Take the missed dose as soon as you remember it. However, if it is within 8 hours of 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. If you vomit after taking a dose, do not replace it and just take the next dose as scheduled.

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

• nausea or vomiting
• feeling tired or sick
• constipation or diarrhea
• joint pain
• shortness of breath or cough
• fever
• rash or swelling
• mouth sores or pain in mouth or throat

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:

• yellowing of skin or eyes, dark urine, loss of appetite, abdominal pain, extreme fatigue

Olutasidenib 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).

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 will order certain lab tests to check your body’s response to olutasidenib.

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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