Ivosidenib (Tibsovo®)

Author: Christina Bach, LCSW, MBE, OSW-C
Last Reviewed: November 06, 2023

Pronounce: EYE-voe-SID-e-nib

Classification: Antineoplastic Isocitrate dehydrogenase (IDH1) inhibitor

About Ivosidenib (Tibsovo®)

This medication is a type of targeted therapy called an isocitrate dehydrogenase (IDH) inhibitor. Ivosidenib works by targeting and blocking IDH1 enzymes. In some cancers, this overactive enzymes cause cells to grow and divide too fast. By inhibiting this enzyme, this medication can slow tumor growth. Your oncology team will test your tumor for this abnormality, which must be present in order to receive the medication.

How to Take Ivosidenib

This medication comes in tablet form that you take by mouth once a day, at about the same time each day. This medication may be taken with or without food, but do not take it with a high fat meal. Take the tablets whole with a glass of water; do not break, crush or chew the tablets.

If a dose is missed or not taken at the usual time, take the dose as soon as you remember, but at least 12 hours before the next scheduled dose. Return to the normal schedule on the following day. Do not take 2 doses within 12 hours. If you vomit a dose, do not take a replacement dose.

It is important to make sure you are taking the correct amount of medication every time. Before every dose, check that what you are taking matches what you have been prescribed.

The blood levels of this medication can be affected by certain foods and medications, so they should be avoided. These include grapefruit, grapefruit juice, Seville oranges (often used in marmalade), St. John's Wort, itraconazole, erythromycin, fluconazole, rifampin, and diltiazem, among others. Be sure to tell your healthcare provider about all medications and supplements you take.

Storage and Handling

Store your medication in the original, labeled container at room temperature and in a dry location (unless otherwise directed by your HCP or Pharmacist). This medication should not be stored in a pillbox. Keep containers out of reach of children and pets.

If a caregiver prepares your dose for you, they should consider wearing gloves or pour the pills directly from their container into the cap, a small cup, or directly into your hand. They should avoid touching the pills. They should always wash their hands before and after giving you the medication. Pregnant or nursing women should not prepare the dose for you. Ask your oncology team where to return any unused medication for disposal. Do not flush down the toilet or throw it in the trash.

Where do I get this medication?

Certain cancer medications, including ivosidenib, are only available through select specialty pharmacies. Your oncology team will work with your prescription drug plan to identify an in-network specialty pharmacy for the distribution of this medication and shipment directly to your home.

Insurance Information

This medication may be covered under your prescription drug plan. Patient assistance may be available to qualifying individuals depending upon prescription drug coverage. Co-pay cards, which reduce the patient co-pay responsibility for eligible commercially (non-government sponsored) insured patients, may also be available. Your care team can help you find these resources if they are available.

Possible Side Effects

There are a number of things you can do to manage the side effects of ivosidenib. Talk to your care team about these recommendations. They can help you decide what will work best for you. These are some of the most common or important side effects:

Differentiation Syndrome

This results from the changes ivosidenib causes to blood cell production in patients with leukemia. Symptoms of differentiation syndrome include fever (temperature >100.4°F or 38°C), sudden weight gain, bone or joint pain, and fluid build-up around the heart, lungs, and/or chest, causing shortness of breath or difficulty breathing. This syndrome is treated with high doses of steroids (like dexamethasone or prednisone) and diuretics (fluid pills). Your healthcare providers will monitor for these signs or symptoms, but it is also important for you to tell your doctor or nurse promptly if you experience any of these symptoms.

Low Red Blood Cell Count (Anemia)

Your red blood cells are responsible for carrying oxygen to the tissues in your body. When the red cell count is low, you may feel tired or weak. You should let your oncology care team know if you experience any shortness of breath, difficulty breathing, or pain in your chest. If the count gets too low, you may receive a blood transfusion.

Diarrhea

Your oncology care team can recommend medications to relieve diarrhea. Also, try eating low-fiber, bland foods, such as white rice and boiled or baked chicken. Avoid raw fruits, vegetables, whole-grain breads, cereals, and seeds. Soluble fiber is found in some foods and absorbs fluid, which can help relieve diarrhea. Foods high in soluble fiber include applesauce, bananas (ripe), canned fruit, orange sections, boiled potatoes, white rice, products made with white flour, oatmeal, cream of rice, cream of wheat, and farina. Drink 8-10 glasses of non-alcoholic, un-caffeinated fluid a day to prevent dehydration.

Decrease in Appetite or Taste Changes

Nutrition is an important part of your care. Cancer treatment can affect your appetite and, in some cases, the side effects of treatment can make eating difficult. Ask your oncology care team about nutritional counseling services at your treatment center to help with food choices.

  • Try to eat five or six small meals or snacks throughout the day, instead of 3 larger meals.
  • If you are not eating enough, nutritional supplements may help.
  • You may experience a metallic taste or find that food has no taste at all. You may dislike foods or beverages that you liked before receiving cancer treatment. These symptoms can last for several months or longer after treatment ends.
  • Avoid any food that you think smells or tastes bad. If red meat is a problem, eat chicken, turkey, eggs, dairy products, and fish without a strong smell. Sometimes cold food has less of an odor.
  • Add extra flavor to meat or fish by marinating it in sweet juices, sweet and sour sauce, or dressings. Use seasonings like basil, oregano, or rosemary to add flavor. Bacon, ham, and onion can add flavor to vegetables.

Leukocytosis (Increased White Blood Cell Count)

This medication can cause your white blood cell count to be higher than normal. Your oncology team will monitor your lab work for this.

Electrolyte Abnormalities

This medication can affect the normal levels of electrolytes (potassium, magnesium) in your body. Your levels will be monitored using blood tests. If your levels become too low, your care team may prescribe specific electrolytes to be given by IV or taken by mouth. Do not take any supplements without first consulting with your care team.

Fatigue

Fatigue is very common during cancer treatment and is an overwhelming feeling of exhaustion that is not usually relieved by rest. While on cancer treatment, and for a period after, you may need to adjust your schedule to manage fatigue. Plan times to rest during the day and conserve energy for more important activities. Exercise can help combat fatigue; a simple daily walk with a friend can help. Talk to your healthcare team for helpful tips on dealing with this side effect.

Muscle or Joint Pain/Aches and Headache

Your healthcare provider can recommend medications and other strategies to help relieve pain

Shortness of Breath (Dyspnea)

This medication can cause cough, shortness of breath, or difficulty breathing. This can also be a sign of a serious side effect of this medication called differentiation syndrome. Any changes in your breathing should be reported to your care team right away.

Swelling (Peripheral Edema)

Peripheral edema is swelling of the extremities caused by the retention of fluid. It can cause swelling of the hands, arms, legs, ankles, and feet. The swelling can become uncomfortable. This can also be a sign of a serious side effect of this medication called differentiation syndrome. Notify your oncology care team if you are experiencing any new or worsening swelling.

Nausea and/or Vomiting

Talk to your oncology care team so they can prescribe medications to help you manage nausea and vomiting. In addition, dietary changes may help. Avoid things that may worsen the symptoms, such as heavy or greasy/fatty, spicy or acidic foods (lemons, tomatoes, oranges). Try saltines, or ginger ale to lessen symptoms.

Call your oncology care team if you are unable to keep fluids down for more than 12 hours or if you feel lightheaded or dizzy at any time.

Mouth Ulcers (Mucositis)

Certain cancer treatments can cause sores or soreness in your mouth and/or throat. Notify your oncology care team if your mouth, tongue, inside of your cheek or throat becomes white, ulcerated or painful. Performing regular mouth care can help prevent or manage mouth sores. If mouth sores become painful, your doctor or nurse can recommend a pain reliever.

  • Brush with a soft-bristle toothbrush or cotton swab twice a day.
  • Avoid mouthwashes that contain alcohol. A baking soda and/or salt with warm water mouth rinse (2 level teaspoons of baking soda or 1 level teaspoon of salt in an eight-ounce glass of warm water) is recommended 4 times daily.
  • If your mouth becomes dry, eat moist foods, drink plenty of fluids (6-8 glasses), and suck on sugarless hard candy.
  • Avoid smoking and chewing tobacco, drinking alcoholic beverages, and citrus juices.

Rash

Some patients may develop a rash, scaly skin, or red itchy bumps. Use an alcohol-free moisturizer on your skin and lips; avoid moisturizers with perfumes or scents. Your oncology care team can recommend a topical medication if itching is bothersome. If your skin does crack or bleed, be sure to keep the area clean to avoid infection. Be sure to notify your oncology care team of any rash that develops, as this can be a reaction. They can give you more tips on caring for your skin.

Fever

Fever can be a side effect of this medication. Contact your care provider for a temperature of 100.4°F / 38°C or greater.

Heart Problems

This medication can cause slow or abnormal heartbeats or an abnormal heart rhythm called QT prolongation. Notify your oncology care team right away if you feel abnormal heartbeats or if you feel dizzy or faint.

Constipation

There are several things you can do to prevent or relieve constipation. Include fiber in your diet (fruits and vegetables), drink 8-10 glasses of non-alcoholic fluids a day, and keep active. A stool softener once or twice a day may prevent constipation. If you do not have a bowel movement for 2-3 days, you should contact your healthcare team for suggestions to relieve constipation.

Increased Liver Enzymes

This medication can cause liver damage, which your oncology care team will monitor for using blood tests called liver function tests. Notify your healthcare provider if you notice yellowing of the skin or eyes, your urine appears dark or brown, or you have pain in your abdomen, as these can be signs of liver problems.

Less common, but important side effects can include:

  • Guillian Barre Syndrome: This is a disorder of the nervous system. Symptoms include weakness, paresthesia (numbness, tingling, prickly or burning skin), poor balance and clumsy walking, difficulty with eye muscles and vision, difficulty swallowing or speaking. Report these symptoms to your care team immediately.

Reproductive Concerns

Exposure of an unborn child to this medication could cause birth defects, so you should not become pregnant or father a child while on this medication. Effective birth control is necessary during treatment. Even if your menstrual cycle stops or you believe you are not producing sperm, you could still be fertile and conceive. You should not breastfeed while taking this medication and for 1 month after completing treatment.