Ivosidenib 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 3 months after starting treatment with ivosidenib. 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 ivosidenib 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 ivosidenib.

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

Ivosidenib 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). Ivosidenib is also used alone or in combination with azacitidine (Onureg) to treat a certain type of AML in some adults older than 75 years of age as a first treatment. Ivosidenib is also used in adults who have already received previous treatment(s) to treat a certain type of cholangiocarcinoma (bile duct cancer) that has spread to nearby tissues or other parts of the body. Ivosidenib is also used to treat certain types of myelodysplastic syndromes in adult patients that have not responded to other treatments or have returned. Ivosidenib is in a class of medications called IDH1 inhibitors. It works by slowing or stopping the growth of cancer cells.

Ivosidenib comes as a tablet to take by mouth. It is usually taken with or without food once daily. Do not take it with a high fat food such as eggs, butter, whole-milk dairy products (such as whole milk, cheese, and yogurt), fried foods, or fast food. Take ivosidenib at around the same time 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 ivosidenib 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 ivosidenib, do not take another dose. Continue your regular dosing schedule.

Your doctor may reduce your dose or temporarily or permanently stop your treatment with ivosidenib 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.

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 ivosidenib,

• tell your doctor and pharmacist if you are allergic to ivosidenib, any other medications, or any of the ingredients in ivosidenib tablets. 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. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• tell your doctor if you or anyone in your family has or has ever had a prolonged QT interval (condition that increases the risk of developing an irregular heartbeat that may cause fainting or sudden death); if you have or have ever had a slow or irregular heartbeat, heart failure, or other heart problems; low blood levels of sodium, potassium, calcium, or magnesium; nervous system problems; liver disease, including cirrhosis; or if you are receiving dialysis treatments or if you have or ever had kidney disease.
• tell your doctor if you are pregnant or plan to become pregnant, or are breastfeeding. You should know that ivosidenib may decrease the effectiveness of hormonal contraceptives (birth control pills, patches, rings, or injections) while you are taking this medication. Talk to your doctor about using another form of birth control. If you become pregnant while taking ivosidenib, call your doctor immediately. Ivosidenib may cause fetal harm.
• tell your doctor if are breastfeeding. Do not breastfeed during your treatment with ivosidenib and for 1 month after your final dose.

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

Make sure you drink plenty of water or other fluids every day while you are taking ivosidenib.

If your next dose is due in 12 hours or more, take the missed dose as soon as you remember it. However, if the next dose will be taken in less than 12 hours, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

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

• headache
• fatigue
• joint or muscle pain
• diarrhea
• constipation
• vomiting
• nausea
• decreased appetite
• mouth pain and ulcers
• stomach pain
• difficulty falling asleep or staying asleep

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:

• dizziness, lightheadedness, or fainting
• weakness or tingling sensation in legs, arms, or upper body; numbness and pain on one side or both sides of the body; changes in your ability to see, touch, hear, or taste; burning or prickling sensation; or difficulty breathing
• chest pain

Ivosidenib 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.

Your doctor will order a lab test before you begin your treatment to see whether your cancer can be treated with ivosidenib.

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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