Tositumomab

Tositumomab is a prescription medication used to treat non-Hodgkin's lymphoma (cancer that begins in the cells of the immune system). Tositumomab belongs to a group of drugs called monoclonal antibodies with radioisotopes. It works by attaching to cancer cells and releasing radiation to damage the cancer cells.

Tositumomab injection comes as a liquid to be injected into a vein by a doctor who has been trained to treat patients with radioactive medication.

Common side effects include low blood counts, infections, and fever.

Tositumomab is a prescription medication used to treat non-Hodgkin's lymphoma (cancer that begins in the cells of the immune system).

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

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

• Bexxar

Common side effects include the following:

• low blood counts
• infections
• infusion reactions
• weakness
• fever
• nausea

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.
 

No drug interactions have been studied. However, you should tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Not all drug interactions are known or reported and new drug interactions are continually being reported.

• Tositumomab injection may cause serious or life-threatening allergic reactions. Tell your doctor if you are allergic to 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 taken a medication made from murine proteins. If so, you may be more likely to have an allergic reaction to tositumomab injection. Your doctor will order tests to see if you are likely to have an allergic reaction to tositumomab injection.
• Tell your doctor right away if you experience any of the following symptoms of allergic reaction while you are receiving a dose of tositumomab injection or during the first few days after you receive a dose of tositumomab injection: rash; hives; itching; swelling of the eyes, face, lips, tongue, throat, arms, hands, feet, ankles, or lower legs; tightening of the throat; wheezing; difficulty breathing or swallowing; or redness, swelling, or tenderness in the place where the medication was injected.
• Treatment with tositumomab injection may cause a severe or life-threatening decrease in the number of blood cells in your body. This decrease in blood cells may happen 4 to 7 weeks after your treatment with tositumomab injection and may last for 30 days or longer. This decrease in blood cells may cause serious or life-threatening bleeding or infection. Your doctor will not give you tositumomab injection if your blood cells have been severely affected by cancer 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; shortness of breath; unusual bruising or bleeding; or sore throat, fever, chills, cough, and other signs of infection.
• Tell your doctor if you are pregnant or plan to become pregnant. Tositumomab injection may harm the fetus. If you are a female, your doctor will order a pregnancy test to be sure you are not pregnant before giving you tositumomab injection. Tositumomab injection may damage reproductive cells in men and women, so you will need to use birth control to prevent pregnancy in you or your partner during your treatment and for up to 12 months after your treatment. Talk to your doctor about an effective method of birth control to use during treatment with tositumomab. If you or your partner becomes pregnant during or up to 12 months after your treatment with tositumomab injection, call your doctor immediately.
• Tositumomab injection is a radioactive medication. It may only be given by doctors who have been trained to give radioactive medications and who have been certified by the manufacturer of tositumomab injection to give the medication.
• Some people who received tositumomab injection developed other forms of cancer including leukemia (cancer that begins in the white blood cells), myelodysplastic syndrome (condition in which blood cells do not develop normally), skin cancer, and other types of cancer or tumors. Talk to your doctor about the risks of receiving tositumomab injection.

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 tositumomab injection,

• tell your doctor and pharmacist if you are allergic to tositumomab or any of the ingredients in tositumomab 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 kidney or thyroid disease.
• tell your doctor if you are breastfeeding.
• if you are having surgery, including dental surgery, tell the doctor or dentist that you have received tositumomab injection.
• do not have any vaccinations without talking to your doctor.
• you should know that the radioactive material in tositumomab injection may be present in your body for 1 to 2 weeks after you receive your last dose. You will need to take certain precautions to prevent the radiation from spreading to others who come in contact with you. Your doctor will explain these precautions to you and will also give you this information in writing. Follow these directions carefully, and ask your doctor if you have any questions.
• you should know that tositumomab injection may damage your thyroid gland. You will need to take medication to protect your thyroid gland beginning the day before you receive your first dose of tositumomab injection and continuing until 14 days after you receive the second dose of tositumomab injection. If you are unable to take the medication needed to protect your thyroid gland, your doctor will not give you tositumomab injection. After your treatment with tositumomab injection, you will need to visit your doctor once a year to check whether your thyroid gland has been damaged. If your thyroid gland is damaged, you will need to take a daily medication for the rest of your life.
• you should know that if you receive tositumomab 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 tositumomab injection, be sure to tell all of your doctors that you have been treated with tositumomab 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.

situmomab injection may harm the fetus. If you are a female, your doctor will order a pregnancy test to be sure you are not pregnant before giving you tositumomab injection. Tositumomab injection may damage reproductive cells in men and women, so you will need to use birth control to prevent pregnancy in you or your partner during your treatment and for up to 12 months after your treatment. Talk to your doctor about an effective method of birth control to use during treatment with tositumomab. If you or your partner becomes pregnant during or up to 12 months after your treatment with tositumomab injection, call your doctor immediately.

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

It is expected that tositumomab would be present in human milk. Because of the possibility for adverse reactions in nursing infants from tositumomab, 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.

Tositumomab injection comes as a liquid to be injected into a vein by a doctor who has been trained to treat patients with radioactive medication. It is given as part of a specific cancer treatment regimen. In order to receive the tositumomab injection treatment regimen, you will make 4 visits to the medical facility over 1 to 2 weeks. On the first visit, you will receive an infusion of tositumomab injection without radioactive material, followed by an infusion of tositumomab injection with radioactive material. The first infusion will last about 60 minutes, and the second infusion about 30 minutes. On the same day, you will undergo an imaging scan (test that shows a picture of all or part of the inside of the body) to see how tositumomab injection has spread through your body. On the second and third visits, you will undergo additional imaging scans to see how tositumomab injection has spread through your body. If tositumomab has spread through your body as expected, you will receive another infusion of tositumomab injection lasting 60 minutes, followed by an infusion of tositumomab injection with radioactive material lasting 30 minutes.

You may experience unpleasant symptoms during or shortly after your infusion with tositumomab injection. Your doctor will give you medication before you receive tositumomab injection to help prevent these symptoms.

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

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

If 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 to check your body's response to tositumomab injection during your treatment and for at least 10 weeks after your treatment.