Vandetanib

Vandetanib is a prescription medication used to treat medullary thyroid cancer that cannot be treated by surgery or that has spread to other parts of the body. Vandetanib belongs to a group of drugs called kinase inhibitors which work by blocking the action of a protein that signals cancer cells to multiply.

This medication comes in tablet form and is usually taken once daily, with or without food.

Common side effects of vandetanib include diarrhea, nausea, rash, and acne.

Vandetanib is a prescription medicine used to treat medullary thyroid cancer that cannot be removed by surgery or that has spread to other parts of the body. 

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

Vandetanib may be found in some form under the following brand names:

• Caprelsa

Vandetanib may cause serious side effects, including:

• See “Drug Precautions”.
• Serious skin reactions. Vandetanib can cause a serious skin reaction, called Stevens-Johnson syndrome or other serious skin reactions that may affect any part of your body. These serious skin reactions may be life threatening and you may need to be treated in a hospital. Call your healthcare provider right away if you experience any of these symptoms.
  • Skin rash or acne
  • Dry skin
  • Itching
  • Blisters on your skin
  • Blisters or sores in your mouth
  • Peeling of your skin
  • Fever
  • Muscle or joint aches
  • Redness or swelling of your face, hands, or soles of your feet
• Breathing problems (interstitial lung disease). Vandetanib may cause a breathing problem called interstitial lung disease that can lead to death. Tell your healthcare provider right away if you experience sudden or worsening shortness of breath or cough.
• Stroke. Strokes have been reported in some people who have taken vandetanib and in some cases have caused death. Stop taking vandetanib and call your healthcare provider right away if you have symptoms of a stroke which may include:
  • numbness or weakness of the face, arm or leg, especially on one side of the body
  • sudden confusion, trouble speaking or understanding
  • sudden trouble seeing in one or both eyes
  • sudden trouble walking, dizziness, loss of balance or coordination
  • sudden, severe headache

• Bleeding. Bleeding can happen during your treatment with vandetanib. Tell your healthcare provider right away if you have severe bleeding while you are taking vandetanib.

• Heart failure. Vandetanib can cause heart failure that can lead to death. You may have to stop taking vandetanib if you have heart failure. Heart failure may not be reversible after stopping vandetanib. Your healthcare provider should monitor you for signs and symptoms of heart failure.

• Diarrhea. Diarrhea is often a symptom of medullary thyroid cancer. Vandetanib can also cause diarrhea or make diarrhea worse. Your healthcare provider should check your blood levels to monitor your electrolytes more frequently if you have diarrhea.

• Thyroid hormones. You can have changes in your thyroid hormone when taking vandetanib. Your healthcare provider should monitor your thyroid hormone levels while taking vandetanib.

• High blood pressure (hypertension). If you develop high blood pressure or your high blood pressure gets worse, your healthcare provider may lower your dose of vandetanib or tell you to stop taking vandetanib until your blood pressure is under control. Your healthcare provider may prescribe another medicine to control your high blood pressure.

• Reversible Posterior Leukoencephalopathy Syndrome (RPLS). A condition called reversible posterior leukoencephalopathy syndrome can happen while taking vandetanib. Call your healthcare provider right away if you have:

  • headaches
  • seizures
  • confusion
  • changes in vision
  • problems thinking

The most common side effects of vandetanib include:

• diarrhea
• rash
• acne
• nausea
• high blood pressure
• headache
• feeling tired
• loss of appetite
• stomach (abdominal) pain

This is not a complete list of vandetanib side effects. Ask your doctor or pharmacist for more information.

Tell your healthcare provider about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements. Vandetanib and other medicines may affect each other causing side effects.

Especially tell your healthcare provider if you take:

• St. John’s Wort. You should not take St. John’s Wort while taking vandetanib.
• certain medicines that can affect how your liver breaks down medicine
• a medicine for your heart

Ask your healthcare provider if you are not sure if your medicine is one listed above.

Do not take other medicines while taking vandetanib until you have talked with your healthcare provider or pharmacist.

Know the medicines you take. Keep a list of them to show your healthcare provider and pharmacist when you get a new medicine.

Vandetanib can cause a change in the electrical activity of your heart called QT prolongation, which can cause irregular heartbeats and that may lead to death. You should not take vandetanib if you have had a condition called long QT syndrome since birth.

Your healthcare provider should perform tests to check the levels of your blood potassium, calcium, magnesium, and thyroid-stimulating hormone (TSH) as well as the electrical activity of your heart with a test called an electrocardiogram (ECG). You should have these tests:

• Before starting vandetanib
• Regularly during vandetanib treatment:
• 2 to 4 weeks after starting vandetanib
• 8 to 12 weeks after starting vandetanib
• Every 3 months thereafter
• If your healthcare provider changes your dose of vandetanib
• If you start taking medicine that causes QT prolongation
• As instructed by your healthcare provider

Your healthcare provider may stop your vandetanib treatment for a while and restart you at a lower dose if you have QT prolongation.

Call your healthcare provider right away if you feel faint, light-headed, or feel your heart beating irregularly while taking vandetanib. These may be symptoms related to QT prolongation.

• Limit exposure to the sun. Vandetanib can make your skin sensitive to the sun. While taking vandetanib and for 4 months after stopping your vandetanib treatment, use sun block and wear clothes that cover your skin, including your head, arms and legs when you go outdoors.

• Use caution before driving or using machinery. Keep in mind vandetanib may make you feel tired, weak, or cause blurred vision.

Medicines can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of vandetanib there are no specific foods that you must exclude from your diet when receiving vandetanib.

Before you take vandetanib, tell your healthcare provider if you:

• have any heart problems, including a condition called congenital long QT syndrome.
• have an irregular heartbeat
• take or have stopped taking a medicine that causes QT prolongation
• have low blood levels of potassium, calcium, or magnesium
• have high blood levels of thyroid-stimulating hormone
• have high blood pressure
• have skin problems
• have a history of breathing problems
• have a recent history of coughing up blood or bleeding
• have diarrhea
• have liver problems
• have kidney problems
• have seizures or are being treated for seizures
• are pregnant or plan to become pregnant. Vandetanib can cause harm to your unborn baby. 
• are breastfeeding or plan to breastfeed. It is not known if vandetanib passes into your breast milk. You and your healthcare provider should decide if you will take vandetanib or breastfeed. You should not do both.

Tell your healthcare provider about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements.

Tell your doctor if you are pregnant or plan to become pregnant. Vandetanib can cause harm to your unborn baby. Talk to your healthcare provider if you are pregnant or plan to become pregnant.

• If you are able to become pregnant, you should use effective birth control during your treatment with vandetanib and for at least 4 months after your last dose of vandetanib.
• Talk to your healthcare provider about birth control methods to prevent pregnancy while you are taking vandetanib.

Tell your doctor if you are breastfeeding or plan to breastfeed. It is not known if vandetanib passes into your breast milk. You and your healthcare provider should decide if you will take vandetanib or breastfeed. You should not do both.

• Take vandetanib exactly as your healthcare provider tells you to take it. Do not change your dose or stop taking vandetanib unless your healthcare provider tells you to.
• Vandetanib may be taken with or without food.
• Swallow vandetanib tablets whole with water.
• Do not crush or chew vandetanib tablets. If vandetanib tablets are accidentally crushed, contact with skin should be avoided. If contact occurs, wash affected areas well with water.

• If you cannot swallow vandetanib tablets whole:

  • place your dose of vandetanib in a glass that contains 2 ounces of noncarbonated water (no other liquids should be used).
  • stir the vandetanib tablet(s) and water mixture for about 10 minutes or until the tablet(s) are in very small pieces (the tablets will not completely dissolve).
  • swallow vandetanib and water mixture right away.
  • if any vandetanib and water mixture remains in the glass, mix with an additional 4 ounces of noncarbonated water and swallow the mixture to make sure that you take your full dose of vandetanib.

• If you miss a dose and your next dose is in:

  • less than 12 hours, take your next dose at the normal time. Do not make up for the missed dose.
  • 12 hours or more, take the missed dose as soon as you remember. Take the next dose at the normal time.

Take vandetanib exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.

The recommended daily dose is 300 mg of vandetanib taken orally. Vandetanib treatment should be continued until patients are no longer benefiting from treatment or an unacceptable toxicity occurs.

If you take too much vandetanib, call your local Poison Control Center or seek emergency medical attention right away.

• Store vandetanib tablets at 59°F to 86°F (15°C to 30°C).
• Safely throw away medicine that is out of date or that you no longer need. Ask your pharmacist how to safely throw away vandetanib tablets.
• Keep vandetanib and all medicines out of the reach of children.

WARNING: QT PROLONGATION, TORSADES DE POINTES, AND SUDDEN DEATH

Vandetanib can prolong the QT interval. Torsades de pointes and sudden death have been reported in patients receiving vandetanib. Vandetanib should not be used in patients with hypocalcemia, hypokalemia, hypomagnesemia, or long QT syndrome. Hypocalcemia, hypokalemia and/or hypomagnesemia must be corrected prior to vandetanib administration and should be periodically monitored. Drugs known to prolong the QT interval should be avoided. If a drug known to prolong the QT interval must be administered, more frequent ECG monitoring is recommended. Given the half-life of 19 days, ECGs should be obtained to monitor the QT at baseline, at 2-4 weeks and 8-12 weeks after starting treatment with vandetanib and every 3 months thereafter. Following any dose reduction for QT prolongation, or any dose interruptions greater than 2 weeks, QT assessment should be conducted as described above. Because of the 19-day half-life, adverse reactions including a prolonged QT interval may not resolve quickly. Monitor appropriately. Only prescribers and pharmacies certified through the vandetanib REMS education program are able to prescribe and dispense vandetanib.