Ofatumumab

This information from Lexicomp^® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.

Brand Names: US

Arzerra; Kesimpta

Brand Names: Canada

Kesimpta

What is this drug used for?

Injection (subcutaneous):

• It is used to treat MS (multiple sclerosis).

IV infusion:

• It is used to treat a type of leukemia.

What do I need to tell my doctor BEFORE I take this drug?

• If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
• If you have an infection.
• If you have active hepatitis B infection.

This is not a list of all drugs or health problems that interact with this drug.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take this drug?

All products:

• Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
• You may have more of a chance of getting an infection. Some infections have been severe or deadly. Wash hands often. Stay away from people with infections, colds, or flu.
• Have blood work checked as you have been told by the doctor. Talk with the doctor.
• Talk with your doctor if you have recently had a vaccine or before getting any vaccines. Vaccine use with this drug may either raise the chance of an infection or make the vaccine not work as well.
• You may need to wait some time after stopping this drug before you have certain vaccines.
• If you are able to get pregnant, talk with your doctor. You may need to use birth control to prevent pregnancy while taking this drug and for some time after your last dose.
• Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.
• If you used this drug when you were pregnant, tell your baby’s doctor.

IV infusion:

• You may bleed more easily. Be careful and avoid injury. Use a soft toothbrush and an electric razor.
• If you are 65 or older, use this drug with care. You could have more side effects.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

All products:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• Signs of infection like fever, chills, very bad sore throat, ear or sinus pain, cough, more sputum or change in color of sputum, pain with passing urine, mouth sores, or wound that will not heal.
• Signs of liver problems like dark urine, tiredness, decreased appetite, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
• Severe side effects have happened during and within 24 hours after getting this drug. Most of the time these happened after the first dose, but they were also seen after later doses. Some of these effects may be life-threatening or deadly. Tell your doctor right away if you have a rash; hives; itching; fast, slow, or abnormal heartbeat; back or muscle pain; chest pain or pressure; fever or chills; flushing; shortness of breath; stomach pain or upset; severe dizziness; passing out; feeling very tired or weak; or severe headache.

IV infusion:

• Feeling very tired or weak.
• Any unexplained bruising or bleeding.
• Swelling in the arms or legs.
• Patients with cancer who take this drug may be at a greater risk of getting a severe health problem called tumor lysis syndrome (TLS). This may lead to death. Call your doctor right away if you have a fast or abnormal heartbeat; any passing out; trouble passing urine; muscle weakness or cramps; upset stomach, throwing up, diarrhea, or not able to eat; or feel sluggish.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

All products:

• Feeling tired or weak.
• Signs of a common cold.

Injection (subcutaneous):

• Itching, redness, swelling, or other reaction where the injection was given.
• Mild fever.
• Headache.

IV infusion:

• Upset stomach.
• Diarrhea.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to your national health agency.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

How is this drug best taken?

Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.

Injection (subcutaneous):

• It is given as a shot into the fatty part of the skin on the top of the thigh, belly area, or upper arm.
• If you will be giving yourself the shot, your doctor or nurse will teach you how to give the shot.
• Wash your hands before and after use.
• Do not shake.
• Let this drug come to room temperature before using it. Leave it at room temperature for 15 to 30 minutes. Do not heat this drug.
• Move the site where you give the shot with each shot.
• Do not give into skin that is irritated, tender, bruised, red, scaly, hard, scarred, or has stretch marks.
• Do not give into a mole.
• Do not give into skin within 2 inches (5 cm) of the belly button.
• Do not use if the solution is not clear to slightly cloudy, is leaking, or has particles.
• Do not use if solution changes color.
• Each prefilled pen or syringe is for 1 use only. Throw away the used pen or syringe after the dose is given.
• Throw away needles in a needle/sharp disposal box. Do not reuse needles or other items. When the box is full, follow all local rules for getting rid of it. Talk with a doctor or pharmacist if you have any questions.

Prefilled syringes or pens:

• Do not remove the cap until you are ready to use. Do not try to put the cap back on. Use within 5 minutes of removing the cap.
• If you drop the pen, do not use if it is damaged or if you dropped it with the cap off.

Prefilled syringes:

• Do not remove the cap or cover until ready to use.
• This drug has a needle guard that will cover the needle after the injection is done. Do not touch the syringe wings before use. This may make the needle guard cover the needle too soon.

IV infusion:

• It is given as an infusion into a vein over a period of time.
• Other drugs may be given to help with infusion side effects.

What do I do if I miss a dose?

Injection (subcutaneous):

• If you miss a dose of this drug within the first 3 weeks of taking it, call your doctor to find out what to do.
• If you miss a dose of this drug after the first 3 weeks of taking it, take a missed dose and start a new schedule based on when the dose is given.
• Do not take 2 doses at the same time or extra doses.

IV infusion:

• Call your doctor to find out what to do.

How do I store and/or throw out this drug?

Injection (subcutaneous):

• Store in a refrigerator. Do not freeze.
• Store in the original container to protect from light.
• If needed, this drug may be stored at room temperature for up to 7 days. If stored at room temperature and not used within 7 days, throw this drug away.
• This drug may be returned to the refrigerator after being stored at room temperature. It must be used within the next 7 days. If this drug is not used within 7 days after being returned to the refrigerator, throw it away.

IV infusion:

• If you need to store this drug at home, talk with your doctor, nurse, or pharmacist about how to store it.

All products:

• Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
• Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

General drug facts

• If your symptoms or health problems do not get better or if they become worse, call your doctor.
• Do not share your drugs with others and do not take anyone else’s drugs.
• Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
• Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
• If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Consumer Information Use and Disclaimer

This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider’s examination and assessment of a patient’s specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at https://www.wolterskluwer.com/en/know/clinical-effectiveness-terms.

Last Reviewed Date

2024-04-26

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