TIBSOVO contains the active ingredient ivosidenib, which is an inhibitor of the isocitrate dehydrogenase 1 (IDH1) enzyme. It is available in the form of a 250 mg film-coated tablet for oral administration. Key inactive ingredients include colloidal silicon dioxide, microcrystalline cellulose, and magnesium stearate.

How should I use this medication?

Take this medication by mouth with water. Take it as directed on the prescription label at the same time every day. Do not cut, crush, or chew this medication. Swallow the tablets whole. You can take it with or without food. If it upsets your stomach, take it with food. Do not take it with a high-fat meal. Keep taking it unless your care team tells you to stop.

Do not take this medication with grapefruit juice.

A special MedGuide will be given to you by the pharmacist with each prescription and refill. Be sure to read this information carefully each time.

Talk to your care team about the use of this medication in children. Special care may be needed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, take it as soon as you can unless it is less than 12 hours before the next dose. If it is less than 12 hours before the next dose, skip the missed dose. Take the next dose at the normal time.

If you vomit after taking a dose, skip it. Take your next dose at the normal time. Do not take extra or 2 doses at the same time to make up for the missed dose.

Where should I keep my medication?

Keep out of the reach of children and pets.

Store at room temperature between 20 and 25 degrees C (68 and 77 degrees F). Protect from moisture. Keep the container tightly closed. Do not throw out the packet in the container. It keeps the medication dry. Get rid of any unused medication after the expiration date.

To get rid of medications that are no longer needed or have expired:

• Take the medication to a medication take-back program. Check with your pharmacy or law enforcement to find a location.
• If you cannot return the medication, check the label or package insert to see if the medication should be thrown out in the garbage or flushed down the toilet. If you are not sure, ask your care team. If it is safe to put it in the trash, take the medication out of the container. Mix the medication with cat litter, dirt, coffee grounds, or other unwanted substance. Seal the mixture in a bag or container. Put it in the trash.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible:

• Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
• Fever, cough, dizziness, feeling faint or lightheaded, shortness of breath, bone pain, sudden weight gain, swelling of the ankles, hands, or feet, which may be signs of differentiation syndrome
• Heart rhythm changes—fast or irregular heartbeat, dizziness, feeling faint or lightheaded, chest pain, trouble breathing
• High white blood cell level—fever, fatigue, trouble breathing, night sweats, change in vision, weight loss
• Pain, tingling, or numbness in the hands or feet, muscle weakness, change in vision, confusion or trouble speaking, loss of balance or coordination, trouble walking, seizures

Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):

• Constipation
• Diarrhea
• Fatigue
• Joint pain
• Loss of appetite
• Nausea
• Pain, redness, or swelling with sores inside the mouth or throat

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

• Guillain-Barre syndrome
• Heart disease
• Irregular heartbeat or rhythm
• Kidney disease
• Liver disease
• Low levels of sodium, potassium, or magnesium in the blood
• Nervous system problems
• An unusual or allergic reaction to ivosidenib, other medications, foods, dyes, or preservatives
• Pregnant or trying to get pregnant
• Breastfeeding

What may interact with this medication?

Do not take this medication with any of the following:

• Cisapride
• Dronedarone
• Pimozide
• Thioridazine

This medication may also interact with the following:

• Certain antivirals for HIV or hepatitis
• Certain medications for fungal infections, such as fluconazole, itraconazole, ketoconazole
• Certain medications for irregular heart beat, such as amiodarone, encainide, flecainide, propafenone, quinidine
• Certain medications for seizures, such as carbamazepine, phenobarbital, phenytoin
• Estrogen and progestin hormones
• Grapefruit juice
• Other medications that cause heart rhythm changes
• Rifampin
• St. John's wort

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Your condition will be monitored carefully while you are receiving this medication.

This medication may make you feel generally unwell. This is not uncommon as chemotherapy can affect healthy cells as well as cancer cells. Report any side effects. Continue your course of treatment even though you feel ill unless your care team tells you to stop.

You may need blood work while taking this medication.

Talk to your care team if you may be pregnant. Serious birth defects can occur if you take this medication during pregnancy. Contraception is recommended while taking this medication. Your care team can help you find the option that works for you.

Do not breastfeed while taking this medication and for 1 month after the last dose.

This medication may cause infertility. Talk to your care team if you are concerned about your fertility.

What are the most serious risks of this medication?

This medication can cause differentiation syndrome. This is a serious but common condition that affects your blood cells. It can be life-threatening if not treated right away. Talk to your care team right away if you have fever, cough, dizziness, feel faint or lightheaded, have shortness of breath, bone pain, sudden weight gain, or swelling of the ankles, hands, or feet.