Ofatumumab Injection (Multiple Sclerosis)

Are there other uses for this medicine?

Ofatumumab is also used and available through a special access program for chronic lymphocytic leukemia (CLL).

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Ofatumumab injection comes as a solution (liquid) in a prefilled dosing pen and a prefilled syringe to inject subcutaneously (under the skin) into your stomach, thigh, or upper arm. Inject once a week for the first 3 doses and then once monthly starting at week 4 of treatment for as long as your doctor recommends that you receive treatment.

Use ofatumumab injection exactly as directed. Do not inject more or less of it or inject it more often than prescribed by your doctor.

You will receive your first subcutaneous dose of ofatumumab injection in your doctor's office. After that, your doctor may allow you to inject ofatumumab or have a caregiver perform the injections. Before you use ofatumumab injection yourself the first time, read the written instructions that come with it. Ask your doctor or pharmacist to show you or the person who will be injecting the medication how to inject it.

Inject ofatumumab into the thigh or stomach area, except the area 2 inches (5 centimeters) around your navel. If a caregiver is giving you the injection, that person can also inject the medication into your upper arms. Use a different site for each injection. Do not inject into an area where the skin is tender, bruised, red, or hard or where you have scars, moles, or stretch marks.

Remove the prefilled dosing pens or prefilled syringes from the refrigerator 15 to 30 minutes before you are ready to inject the medication. Do not remove the needle cover from the prefilled syringe during this time. Check that the expiration date printed on the package has not passed. The liquid should be clear and colorless to slightly brownish-yellow and should not be cloudy or discolored or contain particles. Call your pharmacist if you notice any problems.

Do not shake the dosing pen or syringe. Be careful not to drop the medication onto a hard surface because this may damage the syringe or needle.

Never reuse or share dosing pens or syringes. Dispose of pens and syringes in a puncture-resistant container. Ask your doctor or pharmacist how to dispose of the puncture resistant container.

You may experience a reaction, usually within 24 hours after your injection. This reaction is most likely to occur after your first injection, but could happen at any time during your treatment. Call your doctor if you experience any of the following symptoms during or after your injection: bruising, pain, redness, swelling, or tenderness at the injection site; fever; headache; muscle pain; chills; or tiredness.

What special precautions should I follow?

Before receiving ofatumumab,

• tell your doctor or pharmacist if you are allergic to this drug, any part of this drug, or any otherdrugs, foods or substances. Tell your doctor or pharmacist about the allergy and whatsymptoms you had.

• tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take while receiving ofatumumab injection. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.

• tell your doctor if you have or have ever had hepatitis B infection (swelling of the liver caused by a virus). Your doctor will probably tell you not to use ofatumumab injection.

• tell your doctor if you have or have ever had liver disease.

• tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while receiving ofatumumab, call your doctor immediately.

• you should use birth control during your treatment with ofatumumab injection and for 6 months after the final dose. Talk to your doctor about what birth control is right for you.

• check with your doctor to see if you need to receive any vaccinations before receiving ofatumumab. Tell your doctor if you have received a vaccine within the past 4 weeks. Do not have any vaccinations without talking to your doctor during your treatment.

• using ofatumumab injection may decrease your ability to fight infection and increase the risk that you will get a serious or life-threatening infection. Tell your doctor if you have an infection now or if you have any signs of infection such as fever, chills, or flu-like symptoms. If you experience any of the following symptoms during your treatment with ofatumumab, call your doctor: fever; chills; cough; flu-like symptoms; painful, difficult, or frequent urination; or other signs of infection.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget to take a dose?

If you miss a dose during the first 3 weeks of treatment, talk to your doctor. If you miss a monthly dose of ofatumumab injection, inject it as soon as possible and then continue giving your doses a month apart.

What side effects can this medicine cause?

Ofatumumab may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• headache
• pain, redness, or swelling at the site of injection

Some side effects can be serious. If you experience any of these symptoms or those in the SPECIAL PRECAUTIONS section, call your doctor immediately or get emergency medical treatment:

• weakness on one side of body or clumsiness of limb, new or sudden changes in thinking, confusion, dizziness, loss of balance, difficulty talking or walking, personality changes, or new or sudden changes in vision
• rash; hives; trouble breathing; swelling of the face, eyelids, lips, mouth, tongue and throat; feeling faint; or chest tightness
• feeling tired or weak, nausea, vomiting, dark urine, yellowing of the skin or eyes

Ofatumumab injection may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it in the refrigerator and away from light until the time of use; do not freeze.

Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location – one that is up and away and out of their sight and reach. https://www.upandaway.org

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website https://goo.gl/c4Rm4p for more information.

What should I do in case of overdose?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory.

Do not let anyone else use your medication. Ask your pharmacist any questions you have about refilling your prescription.

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.

Brand name(s)

• Kesimpta^®