Ofatumumab (By injection)

Ofatumumab (oh-FAT-oo-moo-mab)

Treats chronic lymphocytic leukemia (CLL) and relapsing forms multiple sclerosis (MS).

Brand Name(s):

Arzerra, Kesimpta Sensoready Pen

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

This medicine is not right for everyone. You should not receive it if you had an allergic reaction to ofatumumab, if you are pregnant, or if you have an active hepatitis B infection.

How to Use This Medicine:

Injectable

  • Arzerra®:
    • Medicines used to treat cancer are very strong and can have many side effects. Before receiving this medicine, make sure you understand all the risks and benefits. It is important for you to work closely with your doctor during your treatment.
    • Your doctor will prescribe your dose and schedule. This medicine is given through a needle placed in a vein. This medicine needs to be given slowly, so the needle will remain in place for at least an hour.
    • You will receive this medicine while you are in a hospital or cancer treatment center. A nurse or other trained health professional will give you this medicine.
  • Kesimpta®:
    • Your doctor will prescribe your exact dose and tell you how often it should be given. This medicine is given as a shot under your skin. It is usually given at the front of your thighs, stomach, or upper arms.
    • A nurse or other health provider will give you this medicine.
    • You may be taught how to give your medicine at home. Make sure you understand all instructions before giving yourself an injection. Do not use more medicine or use it more often than your doctor tells you to.
    • Remove the prefilled syringe or pen from the refrigerator before using. Allow the medicine to warm to room temperature for 15 to 30 minutes. Do not remove the needle cover while allowing to reach room temperature.
    • Check the liquid in the prefilled syringe or pen. It should be clear to slightly cloudy and colorless to slightly brownish-yellow. Do not use it if it is cloudy, discolored, or has particles in it. Do not shake. Do not use the prefilled syringe or pen if it has been damaged, broken, or if you dropped it with the cap removed.
    • You will be shown the body areas where this shot can be given. Use a different body area each time you give yourself a shot. Keep track of where you give each shot to make sure you rotate body areas. Do not inject into skin areas that are tender, bruised, red, scaly, or hard, or areas with moles, scars, or stretch marks.
    • This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
    .
  • Missed dose: This medicine needs to be given on a fixed schedule. If you miss a dose, call your doctor, home health caregiver, or treatment clinic for instructions.
  • If you store this medicine at home, keep it in the refrigerator. Do not freeze. Keep the medicine in its original container. Protect it from light.
  • Do not reuse syringes and needles. Throw away used pens syringes in a hard, closed container that the needles cannot poke through. Keep this container away from children and pets.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Some medicines can affect how ofatumumab works. Tell your doctor if you are also using medicine that weakens the immune system, including a steroid medicine.
  • This medicine may interfere with vaccines. Ask your doctor before you get a flu shot or any other vaccines. You should have completed any needed vaccines at least 4 weeks for live or live-attenuated vaccines and at least 2 weeks for non-live (inactivated) vaccines before treatment with this medicine.

Warnings While Using This Medicine:

  • It is not safe to take this medicine during pregnancy. It could harm an unborn baby. Tell your doctor right away if you become pregnant. Use an effective form of birth control to keep from getting pregnant during treatment and for at least 6 months after the last dose.
  • Tell your doctor if you are breastfeeding, or if you have liver disease, any type of infection, a weak immune system, or a history of hepatitis B infection.
  • This medicine may cause the following problems:
    • Infusion reactions
    • Tumor lysis syndrome
    • Hepatitis B infection
    • Progressive multifocal leukoencephalopathy (PML)
  • This medicine may make you bleed, bruise, or get infections more easily. Take precautions to prevent illness and injury. Wash your hands often.
  • Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Change in how much or how often you urinate, trouble urinating, painful urination
  • Chest pain, trouble breathing
  • Confusion, dizziness, loss of balance, trouble speaking or understanding, vision problems
  • Dark urine or pale stools, nausea, vomiting, loss of appetite, stomach pain, yellow skin or eyes
  • Fever, chills, cough, runny or stuffy nose, sore throat, and body aches
  • Unusual bleeding, bruising, or weakness
  • Warmth or redness in your face, neck, arms, or upper chest

If you notice these less serious side effects, talk with your doctor:

  • Back pain, headache
  • Pain, itching, burning, swelling, bleeding, or a lump under your skin where the needle is placed

If you notice other side effects that you think are caused by this medicine, tell your doctor

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


Last Updated: 11/6/2020


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