Ibritumomab

(ib-rih-TOO-mo-mab)

Trade name: Zevalin^TM
Other name: Ibritumomab Tiuxetan

Chemocare.com uses generic names in all descriptions of drugs. Zevalin is the trade name for ibritumomab. ibritumomab tiuxetan is another name for ibritumomab. In some cases, health care professionals may use the trade name zevalin or other names ibritumomab tiuxetan when referring to the generic drug name ibritumomab.

Drug type: Ibritumomab is a monoclonal antibody that is linked with a radioactive substance Yttrium-90. (For more detail, see "How this drug works" section below).

What Ibritumomab Is Used For:

• Treatment of certain types of non-Hodgkin's lymphoma that have recurred after, or not responded to prior treatment.

Note:  If a drug has been approved for one use, physicians may elect to use this same drug for other problems if they believe it may be helpful.

How Ibritumomab Is Given:

• Infusion into a vein (intravenous, IV).
• Given only as part of a protocol in combination with the drug rituximab (see rituximab).  Two step protocol: 
• Step 1 - Rituximab infusion starting at a slow rate. The rate is increased if no allergic or infusion related events occur (usual infusion time about 4-6 hours).
• Step 2 - 7-9 days following Step 1, rituximab infusion is again given as above.  Within 4 hours of the completion of the rituximab infusion the treatment dose of ibritumomab (ibritumomab linked with yttrium-90) is infused over 10 minutes.
• The amount of ibritumomab that you will receive depends on many factors, including your height and weight, your general health or other health problems, and the type of cancer or condition being treated.  Your doctor will determine your dose and schedule.

Side Effects:

Important things to remember about the side effects of ibritumomab:

• Most people do not experience all of the side effects listed.
• Side effects are often predictable in terms of their onset and duration.
• Side effects are almost always reversible and will go away after treatment is complete.
• There are many options to help minimize or prevent side effects.
• There is no relationship between the presence or severity of side effects and the effectiveness of the medication 

The following side effects are common (occurring in more than 30%) for patients taking ibritumomab:

• Low blood counts.  Your white and red blood cells and platelets may temporarily decrease.  This can put you at increased risk for infection, anemia and/or bleeding.  (This effect may be delayed or prolonged for several weeks after treatment is given).

Nadir: Meaning low point, nadir is the point in time between chemotherapy cycles in which you experience low blood counts.

Onset: none noted
Nadir: 7-9 weeks
Recovery:

• Weakness
• Nausea

These are less common side effects (occurring in 10-29%) for patients receiving ibritumamab:

• Infection 
• Fever, chills (see flu-like symptoms)
• Abdominal pain 
• Shortness of breath 
• Pain 
• Headache 
• Vomiting 
• Cough, throat irritation   
• Dizziness 
• Diarrhea

A serious but rare side effect of ibritumomab regimen (in combination with rituximab) is potential for a severe infusion reaction, typically during first rituximab infusion (during infusion or within 30-120 minutes of infusion).

Not all side effects are listed above. Some that are rare (occurring in less than 10% of patients) are not listed here.  However, you should always inform your health care provider if you experience any unusual symptoms.

When to contact your doctor or health care provider:

Contact your health care provider immediately, day or night, if you should experience any of the following symptoms:

• Fever of 100.4° F (38° C) or higher, chills (possible signs of infection)
• Shortness of breath, chest pain or discomfort; swelling of your lips or throat
• Confusion

The following symptoms require medical attention, but are not an emergency.  Contact your health care provider within 24 hours of noticing any of the following:

• Nausea (interferes with ability to eat and unrelieved with prescribed medication)
• Vomiting (vomiting more than 4-5 times in a 24 hour period)
• Diarrhea (4-6 episodes in a 24-hour period)
• Unusual bleeding or bruising
• Black or tarry stools, or blood in your stools or urine
• Extreme fatigue (unable to carry on self-care activities)

Always inform your health care provider if you experience any unusual symptoms.

Precautions:

• Before starting ibritumomab treatment, make sure you tell your doctor about any other medications you are taking (including prescription, over-the-counter, vitamins, herbal remedies, etc.). Do not take aspirin, products containing aspirin unless your doctor specifically permits this.
• Because of the high incidence of low platelet counts associated with ibritumomab, avoid such herbs such as; cat's claw, dong quqi, evening primrose, feverfew, garlic, ginger, ginkgo, red clover, horse chestnut, green tea, ginseng (all have antiplatelet activity).  Discuss with your doctor when it might be safe to resume.
• Do not receive any kind of immunization or vaccination without your doctor's approval while taking ibritumomab.
• Inform your health care professional if you are pregnant or may be pregnant prior to starting this treatment. Pregnancy category D (ibritumomab may be hazardous to the fetus).  Women who are pregnant or become pregnant must be advised of the potential hazard to the fetus.
• For both men and women: Do not conceive a child (get pregnant) while taking ibritumomab. Barrier methods of contraception, such as condoms, are recommended. Discuss with your doctor when you may safely become pregnant or conceive a child after therapy.
• Do not breast feed while taking this medication.

Self-Care Tips:

• Once the radio-labled product (ibritumomab, yttrium 90) is infused, the body is a shield to the low dose of radiation that is emitted.  No special radiation safety precautions are necessary.
• Drink at least two to three quarts of fluid for the first 48 hours after each infusion, unless you are instructed otherwise.
• You may be at risk of infection so try to avoid crowds or people with colds or not feeling well, and report fever or any other signs of infection immediately to your health care provider.
• Wash your hands often.
• Use a soft toothbrush to minimize bleeding.
• Avoid contact sports or activities that could cause injury.
• To reduce nausea, take anti-nausea medications as prescribed by your doctor, and eat small, frequent meals.  
• In general, drinking alcoholic beverages should be kept to a minimum or avoided completely.  You should discuss this with your doctor.
• Get plenty of rest. 
• Maintain good nutrition.
• If you experience symptoms or side effects, be sure to discuss them with your health care team.  They can prescribe medications and/or offer other suggestions that are effective in managing such problems.

Monitoring and Testing:

You will be checked regularly by your healthcare professional after taking ibritumomab, to monitor side effects and check your response to therapy.  Periodic blood work to monitor your complete blood count (CBC) as well as the function of other organs (such as your kidneys and liver) will also be ordered by your doctor.   

How Ibritumomab Works:

Ibritumomab is classified as a monoclonal antibody.  Monoclonal antibodies are a relatively new type of "targeted" cancer therapy.

Antibodies are an integral part of the body's immune system.  Normally, the body creates antibodies in response to an antigen (such as a protein in a germ) that has entered the body.  The antibodies attach to the antigen in order to mark it for destruction by the immune system.

To make anti-cancer monoclonal antibodies in the laboratory, scientists analyze specific antigens on the surface of cancer cells (the targets).  Then, using animal and human proteins, they create a specific antibody that will attach to the target antigen on the cancer cells. When given to the patient, these monoclonal antibodies will attach to matching antigens like a key fits a lock.

Since monoclonal antibodies target only specific cells, they may cause less toxicity to healthy cells.   Monoclonal antibody therapy is usually given only for cancers in which antigens (and the respective antibodies) have been identified already.

Ibritumomab works by targeting the CD20 antigen on normal and malignant B-cells. However, it is more than a monoclonal antibody alone.  In the laboratory, a radioactive substance (yttrium-90) is linked to the antibody.  When the antibody attaches to the CD20 antigens, radiation is delivered directly to the targeted cells, killing the targeted cells as well as cancer cells in the immediate area.  Stem cells (young cells in the bone marrow that will develop into the various types of cells) do not have the CD20 antigen.  This allows healthy B-cells to regenerate after treatment.  This is also known as radioimmunotherapy.

Note:  We strongly encourage you to talk with your health care professional about your specific medical condition and treatments. The information contained in this website is meant to be helpful and educational, but is not a substitute for medical advice.

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