Arzerra (Ofatumumab) belongs to the class of medications called monoclonal antibodies. It is used to treat Chronic Lymphocytic Leukemia (CLL), which is a cancer of the blood that affects white blood cells. In CLL, white blood cells are made too quickly and live too long. Too many white blood cells cause problems in the body. Arzerra (Ofatumumab) works by attaching to the tumour cells and stimulating the body's defenses, resulting in the death of tumour cells.

Arzerra (Ofatumumab) is used in combination with a medication called Chlorambucil to treat CLL in people who have not been previously treated. Arzerra (Ofatumumab) may also be used by people with CLL that has not responded to other treatments.

Arzerra (Ofatumumab) may be available under multiple brand names and/or in several different forms. Any specific brand name of Arzerra (Ofatumumab) may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of Arzerra (Ofatumumab) may not be used for all of the conditions discussed here.

Your doctor may have suggested Arzerra (Ofatumumab) for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking Arzerra (Ofatumumab), speak to your doctor. Do not stop taking Arzerra (Ofatumumab) without consulting your doctor.

Do not give Arzerra (Ofatumumab) to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take Arzerra (Ofatumumab) if their doctor has not prescribed it.

The recommended first dose of Arzerra (Ofatumumab) for people who have received other treatments is 300 mg given by intravenous (into a vein) infusion. After this first dose, 2000 mg is given once a week for 8 weeks, then once every 4 weeks for 4 months.

You may be given medications before each infusion of Arzerra (Ofatumumab) to help decrease reactions to the infusion.  These medications include anithistamines, steroids, and pain relievers.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

Arzerra (Ofatumumab) is usually injected into a vein through a site on your skin that has been specially prepared for this purpose. Very careful handling of this medication is required. Arzerra (Ofatumumab) is always given under the direct supervision of a doctor in a hospital or similar setting with access to sterile equipment for preparation.

It is important Arzerra (Ofatumumab) be given exactly as recommended by your doctor. If you miss an appointment to receive a dose of Arzerra (Ofatumumab) contact your doctor as soon as possible to reschedule your appointment.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Arzerra (Ofatumumab). If you are concerned about side effects, discuss the risks and benefits of Arzerra (Ofatumumab) with your doctor.

The following side effects have been reported by at least 1% of people taking Arzerra (Ofatumumab). Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• back pain
• chills
• Diarrhea
• fatigue
• nausea
• swelling of the hands, feet and ankles
• vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• signs of Anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
• signs of bleeding (e.g., bloody nose, blood in urine, coughing blood, bleeding gums, cuts that don't stop bleeding)
• signs of infection (symptoms may include Fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness)
• signs of an infusion reaction (e.g., nausea, high temperature, rash)
• signs of pneumonia (e.g., cough, fever, difficulty breathing)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• severe infusion reactions (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat, flushing, high blood pressure, shortness of breath, chills/rigors, fever, diarrhea)
• signs of bowel obstruction (persistent abdominal pain, Constipation, diarrhea, bloating)
• signs of a Heart Attack (e.g., chest pain or pressure, pain extending through shoulder and arm, nausea and vomiting, sweating)
• signs of tumour lysis syndrome (e.g., muscle spasms, producing less urine than usual, nausea, cloudy urine, shortness of breath)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Arzerra (Ofatumumab).

Each 1 mL of sterile, clear to opalescent, colourless, preservative free liquid concentrate contains 20 mg Arzerra (Ofatumumab). Nonmedicinal ingredients: arginine, sodium acetate, sodium chloride, polysorbate 80, edetate disodium, hydrochloric acid, and water for injection.

Do not take Arzerra (Ofatumumab) if you:

• are allergic to Arzerra (Ofatumumab) or any ingredients of the medication
• have or have had progressive multifocal leukoencephalopathy (PML)

There may be an interaction between Arzerra (Ofatumumab) and any of the following:

• BCG vaccine
• Belimumab
• Denosumab
• echinacea
• Fingolimod
• Leflunomide
• Natalizumab
• Pimecrolimus
• Roflumilast
• Tacrolimus (topical)
• tofactitinib
• Trastuzumab
• vaccines

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Arzerra (Ofatumumab). Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.