Ibritumomab

Ibritumomab is a prescription medication used in patients with cancer who have been treated with chemotherapy or with rituximab and have not gotten better or have had a relapse. Ibritumomab belongs to a group of drugs called monoclonal antibodies. When combined with a radioactive substance and given with rituximab, it works as a type of radioimmunotherapy to destroy cancer cells.

This medication comes as an injectable form to be given into the vein (IV) by a healthcare professional.

Common side effects include fatigue, nose and throat infection, and nausea. Do not drive or operate heavy machinery until you know how this medicaiton affects you.

ibritumomab is a prescription medication used in patients who have been treated with chemotherapy or with rituximab and have not gotten better or have had a relapse. When combined with a radioactive substance and given with rituximab, it works as a type of radioimmunotherapy.

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

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

• Zevalin

Common side effects include the following:

• low cell counts
• fatigue
• nose and throat infection
• nausea
• stomach pain
• weakness
• cough
• diarrhea
• fever

This is not a complete list of this medication’s side effects. Ask your doctor or pharmacist for more information.

Tell your doctor if you have any side effect that bothers you or that does not go away.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Tell your doctor about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

• medications that affect your platelets such as clopidogrel (Plavix), aspirin, prasugrel (Effient), ticagrelor (Brilinta), ticlopidine (Ticlid), abciximab (ReoPro), eptifibatide (Integrilin), tirofiban (Aggrastat), and cilostazol (Pletal)
• blood thinners such as warfarin (Coumadin, Jantoven)

Serious side effects have been reported with ibritumomab use.

• Several hours before each dose of ibritumomab injection, a medication called rituximab (Rituxan) is given. Some patients have had serious or life-threatening allergic reactions while they received rituximab or shortly after they received rituximab. These reactions have occurred most often with the first dose of rituximab. Some patients have died within 24 hours after receiving rituximab. Tell your doctor if you are allergic to rituximab or medications made from murine (mouse) proteins, or if you are not sure if a medication you are allergic to is made from murine proteins. Also tell your doctor if you have ever been treated with a medication made from murine proteins. If so, you may be more likely to have an allergic reaction to rituximab. Your doctor will order tests to see if you are likely to have an allergic reaction to rituximab.
• Your doctor will give you medication before you receive rituximab to help prevent reactions to rituximab. If you experience a reaction to rituximab, your doctor may stop giving you the medication for a time or may give it to you more slowly. If the reaction is serious, your doctor will stop the rituximab infusion and will not continue your treatment with ibritumomab injection. Tell your doctor right away if you experience any of the following symptoms during or shortly after your treatment with rituximab: cough; difficulty breathing or swallowing; tightening of the throat; hives; itching; swelling of the eyes, face, lips, tongue, mouth, or throat; pain in the chest, jaw, arm, back, or neck; confusion; loss of consciousness; fast heartbeat; sweating; pale skin; fast breathing; decreased urination; or cold hands and feet.
• Treatment with rituximab and ibritumomab injection may cause a severe decrease in the number of blood cells in your body. This decrease may happen 7 to 9 weeks after your treatment and may last for 12 weeks or longer. This decrease may cause serious or life-threatening infections or bleeding. Your doctor will not give you ibritumomab injection if your blood cells have been severely affected by cancer, if you have had a bone marrow transplant, if you have been unable to produce enough stem cells (cells found in the bone marrow that can mature to form any type of blood cell) to have a bone marrow transplant, or if you already have a low number of blood cells. Tell your doctor if you are taking any of the following medications: anticoagulants ('blood thinners') such as warfarin (Coumadin); aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin) and naproxen (Aleve); and clopidogrel (Plavix). If you have any of the following symptoms, call your doctor right away: pale skin; weakness; unusual bruising or bleeding; purple spots or patches on the skin; black or bloody stools; vomit that is bloody or looks like coffee grounds; diarrhea; or sore throat, fever, chills, cough, or other signs of infection.
• Treatment with rituximab and ibritumomab injection may cause serious or fatal skin reactions. These reactions may occur as soon as a few days after treatment or as long as 4 months after treatment. Tell your doctor right away if you develop blisters on your skin or on the inside of your mouth or nose, a rash, or peeling of the skin. Your doctor will not give you any more ibritumomab injection if you develop these symptoms.
• After you receive your first dose of ibritumomab injection, your doctor will order imaging scans (tests that show a picture of all or part of the inside of the body) to see how the medication has spread through your body. If the medication has not spread through your body as expected, you will not receive your second dose of ibritumomab injection.

Do not take this medication if you are allergic to it or to its inactive ingredients.

Medications 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 this medication, there are no specific foods that you must exclude from your diet.

Before receiving ibritumomab injection,

• tell your doctor and pharmacist if you are allergic to ibritumomab, any of the medications mentioned in the Ibritumomab Precautions section, any other medications, or any of the ingredients in ibritumomab injection.
• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take.
• tell your doctor if you have or have ever had any medical condition.
• tell your doctor if you are pregnant, plan to become pregnant or are breastfeeding. 
• if you are having surgery, including dental surgery, tell the doctor or dentist that you have received ibritumomab injection.
• do not have any vaccinations without talking to your doctor.
• you should know that the radioactivity in the second dose of ibritumomab injection may be present in your body fluids for up to a week after you receive the dose. To prevent the radioactivity from spreading to people who are in close contact with you, you should be sure to wash your hands throughly after using the bathroom, use a condom every time you have sexual intercourse, and avoid deep kissing. Follow these precautions during your treatment and for 7 days after you receive your second dose of ibritumomab injection.
• you should know that ibritumomab injection contains albumin (a product that is made from live donor blood). Although there is a extremely small chance that viruses may be spread through the blood, no cases of viral diseases from this product have been reported.
• you should know that if you receive ibritumomab injection, your body may develop antibodies (substances in the blood that help the immune system recognize and attack foreign substances) to murine proteins. If you develop these antibodies, you may have an allergic reaction when you take medications made from murine proteins, or these medications might not work well for you.After your treatment with ibritumomab injection, be sure to tell all of your doctors that you have been treated with ibritumomab injection.

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy. This medication falls into category D.

If you become pregnant while receiving ibritumomab injection, call your doctor immediately. You should use birth control to prevent pregnancy during your treatment and for 12 months after your treatment. Ibritumomab injection may harm the fetus (unborn baby).

Tell your doctor if you are breastfeeding or plan to breastfeed.

Ibritumomab has the potential to cross into human breast milk. Because of the possibility for adverse reactions in nursing infants from ibritumomab, a choice should be made whether to stop nursing or to stop use of this medication. The importance of the drug to the mother should be considered.

Ibritumomab injection comes as a liquid to be injected into a vein over 10 minutes by a doctor who has been trained to treat patients with radioactive medication. It is given as part of a specific cancer treatment regimen. On the first day of the treatment regimen, a dose of rituximab is given and the first dose of ibritumomab injection is given no more than 4 hours afterward. Imaging scans to see how ibritumomab injection has spread through the body are performed 48 to 72 hours after the dose of ibritumomab injection is given. Additional scans may be performed if needed during the next several days. If the results of the scan(s) show that ibritumomab injection has spread through the body as expected, a second dose of rituximab and a second dose of ibritumomab injection will be given 7 to 9 days after the first doses were given.

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

The dose your doctor recommends may be based on the following:

• the condition being treated
• other medical conditions you have
• other medications you are taking
• how you respond to this medication
• your weight
• your height
• your age
• your gender

The recommended dose is 0.3 or 0.4 mCi/kg (14.8 MBq per kg) Y-90 ibritumomab injection.

Since this medication is administered by a healthcare provider in a medical setting, it is unlikely that an overdose will occur. However, if overdose is suspected, seek emergency medical attention.

Keep all appointments with your doctor and the laboratory.Your doctor will order certain tests during your treatment and for up to 3 months after your treatment to check your body's response to ibritumomab.

WARNING: SERIOUS INFUSION REACTIONS, PROLONGED AND SEVERE CYTOPENIAS, and SEVERE CUTANEOUS AND MUCOCUTANEOUS REACTIONS

• Serious Infusion Reactions, some fatal, may occur within 24 hours of rituximab infusion. 
• Prolonged and Severe Cytopenias occur in most patients. 
• Severe Cutaneous and Mucocutaneous Reactions, some fatal, reported with ibritumomab therapeutic regimen. 
• Do not exceed 32 mCi (1184 MBq) of Y-90 Ibritumomab.