December 2, 2008

ibritumomab tiuxetan

By Anonymous User

Class: Biologic therapy

Generic Name: Ibritumomab (i-bri-TOO-moe-mab), ibritumomab tiuxetan
Trade Name: Zevalin™

How is this drug used? Ibritumomab is FDA approved for relapsed or refractory low-grade, follicular, or transformed B-cell non-Hodgkin’s lymphoma, including patients who have already been treated with rituximab. It is important for patients to remember that physicians have the ability to prescribe medication for conditions other than those for which the drug has been approved by the FDA. Patients who have received a prescription of this drug for a condition other than which it is approved may wish to discuss this issue with their physician.

What is the mechanism of action? Ibritumomab is a type of agent called a radioimmunotherapeutic. It is comprised of two different portions: a monoclonal antibody and a radioactive isotope. The monoclonal antibody portion has been developed through laboratory processes to bind to a particular part of B-cells, which comprise the majority of cancerous cells in non-Hodgkin's lymphoma. It is thought that this binding action stimulates the immune system to attack the cancer cells. In addition, the radioisotope that is attached to the monoclonal antibody spontaneously emits radiation, killing cancer cells in a second manner.

How is ibritumomab given (administered)? Ibritumomab is administered intravenously (into a vein) and the dose depends on several factors, including the condition being treated, the size of the patient, the particular treatment regimen being used and the overall health of the patient. Initially, patients undergo administration of the monoclonal antibody rituximab (Rituxan®). Seven to nine days following the initial dose of rituximab, patients receive an additional dose of rituximab followed by ibritumomab.  Since rituximab is an integral component of treatment with ibritumomab, patients may wish to view the package insert of rituximab.  Rarely, patients experience severe reactions during administration of the rituximab infusion and ibritumomab regimen. Although patients will be closely monitored for this reaction, they should tell their healthcare provider immediately if they experience the following symptoms: shortness of breath, difficulty breathing, chest pain, noticeable changes in heart rate or rhythm, fever, chills, hives, flushing, lightheadedness or dizziness. Patients may also experience low blood pressure and fluid accumulation as part of this reaction.

Physicians and nurses who are trained in administration and management of radioactive agents, called nuclear medicine specialists, are in charge of patients treated with this type of drug.  Patients may need to travel to special medical facilities for treatment or larger hospitals may have nuclear medicine facilities within the hospital.

How are patients monitored? Patients will usually have scheduled meetings with their healthcare provider while they are being treated with ibritumomab.  Typically, blood will be drawn to check levels of blood cells and to monitor functions of some organ systems, such as the kidneys or liver.  Patients may also undergo physical examinations, scans or other measures to assess tolerance and response to therapy.

What are the common (occur in 30% or more of patients) side effects of treatment with ibritumomab?

• Low white blood cell levels – increases the risk of infection
• Low red blood cell levels – increases the risk of anemia
• Low platelet levels – increases the risk of bleeding
• Generalized weakness
• Nausea

What are the less common (occur in 10% to 29% of patients) side effects of treatment with ibritumomab?

• Infection
• Fever
• Chills
• Abdominal pain
• Shortness of breath
• Pain
• Headache
• Vomiting
• Cough
• Irritation of the throat
• Dizziness
• Diarrhea

What are the possible late side effects of treatment with ibritumomab? Treatment with ibritumomab may increase the risk of developing a secondary malignancy.  A secondary malignancy is a new and unrelated cancer that occurs in an individual as a result of previous treatment with radiation or chemotherapy.  Patients should ask their physician about the possibility of developing a secondary malignancy as a result of their treatment.

This is not a complete list of side effects. Some patients may experience other side effects that are not listed here. Patients may wish to discuss with their physician the other less common side effects of this drug, some of which may be serious.

Some side effects may require medical attention. Other side effects do not require medical attention and may go away during treatment. Patients should check with their physician about any side effects that continue or are bothersome.

What can patients do to help alleviate or prevent discomfort and side effects?

• Pay careful attention to the physician’s instructions and inform the physician of any side effects.
• Maintain adequate rest and nutrition.
• Wear sunscreen and protective clothing and try to minimize sun exposure.
• Drink plenty of fluids. (Patients should ask their physician about the amount of liquid to consume during a day.)
• If possible, avoid large crowds or people who are sick or not feeling well, as this drug may leave some patients susceptible to infection.
• Wash hands often to reduce the risk of infection.
• Eat small meals frequently to help alleviate nausea.
• Avoid activities that may cause injury or bruising.
• Use a soft toothbrush and an electric razor to prevent cuts on the mouth or skin.

Are there any special precautions patients should be aware of before starting treatment?

• Although ibritumomab is a radiopharmaceutical agent, patients typically do not have to take special radiation precautions.
• Patients should inform their physician if they are pregnant, breastfeeding or planning a family in the near future. This drug may cause birth defects. It is important to use some kind of birth control while undergoing treatment. Also, patients may want to talk to their physician if they are considering having children in the future, since some drugs may cause fertility problems.
• It is important that patients inform their physician of any pre-existing conditions (chicken pox, heart disease, kidney disease, liver disease, lung disease, etc.) as they may worsen with this drug.
• Patients should inform their physician of any other medication they are taking (whether prescription or over-the-counter, including vitamins, herbs, etc.) as they may interfere with treatment, especially medications that affect blood clotting (blood thinners)..
• Patients should check with their physician before starting any new drug or nutritional supplement.
• Patients should inform their physician of any known drug or food allergies or any reactions to medications they have experienced in the past.

When should patients notify their physician?

• Signs of a reaction to rituximab (see rituximab information) or ibritumomab – difficulty breathing, shortness of breath, chest pain, noticeable changes in heart rate or rhythm, lightheadedness, dizziness, low blood pressure, fever, chills, flushing
• Flu or cold-like symptoms - fever, chills, sore throat, cough
• Signs of infection – redness, swelling, pus, tenderness, painful urination
• Unexplained or excessive bleeding (nosebleeds, bruising, black tarry stools, blood in the urine, etc.)
• Severe or persistent fatigue
• Swelling of extremities
• Shortness of breath, difficulty breathing, cough
• Rash, itching
• Weakness
• Headache
• Persistant nausea or vomiting

What is a package insert?
A package insert is required by the FDA and contains a summary of the essential scientific information needed for the safe and effective use of the drug for healthcare providers and consumers.  A package insert typically includes information regarding specific indications, administration schedules, dosing, side effects, contraindications, results from some clinical trials, chemical structure, pharmacokinetics and metabolism of the specific drug. By carefully reviewing the package insert, you will get the most complete and current information about how to safely use this drug. If you do not have the package insert for the drug you are using, your pharmacist or physician may be able to provide you with a copy.

Copyright © 2010 CancerConnect Last updated 07/10.

Important Limitations of Use

The information provided above on the drug you have selected is provided for your information only and is not a substitute for consultation with an appropriate medical doctor. We are providing this information solely as a courtesy and, as such, it is in no way a recommendation as to the safety, efficacy or appropriateness of any particular drug, regimen, dosing schedule for any particular cancer, condition or patient nor is it in any way to be considered medical advice. Patients should discuss the appropriateness of a particular drug or chemotherapy regimen with their physician.

As with any printed reference, the use of particular drugs, regimens and drug dosages may become out-of-date over time, since new information may have been published and become generally accepted after the latest update to this printed information. Please keep in mind that health care professionals are fully responsible for practicing within current standards, avoiding use of outdated regimens, employing good clinical judgment in selecting drugs and/or regimens, in calculating doses for individual patients, and verifying all dosage calculations.



The prescribing physician is solely responsible for making all decisions relating to appropriate patient care including, but not limited to, drugs, regimens, dose, schedule, and any supportive care.

Tags: Biological Therapy, I