Class Name(s):

• 90:24.28 IgG1 Monoclonal Antibodies

Pronunciation:

• (be lim' ue mab)

Brand Name(s):

• Benlysta^®

WHY is this medicine prescribed?

Belimumab injection is used to treat certain types of lupus (a disease in which the immune system attacks healthy parts of the body such as joints, skin, blood vessels, and organs) including, systemic lupus erythematosus (SLE) and lupus nephritis (a disease in which the immune system attacks the kidneys). Belimumab is in a class of medications called monoclonal antibodies. It works by blocking the activity of a certain protein in people with SLE and lupus nephritis.

HOW should this medicine be used?

Belimumab injection comes as a solution (liquid) in an autoinjector or prefilled syringe to inject subcutaneously (under the skin) either at a doctor's officer or at home by the patient or a caregiver. It also comes as a powder to be mixed with water and injected intravenously (into a vein) over 1 hour by a doctor or nurse in a medical facility. Your doctor will tell you how often you are to receive or use belimumab injection based on your body's response to this medication and age.

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

You will receive your first dose of belimumab injection in your doctor's office. If you will be injecting belimumab at home, your doctor will show you or your caregiver how to inject it. You and/or your caregiver should also read the written instructions for use that come with the medication.

Remove the autoinjector or prefilled syringe from the refrigerator. Place on a flat surface away from direct sunlight. Do not remove the needle cover. Allow it to reach room temperature for 30 minutes before you inject the medication. Do not try to warm the medication by heating it in a microwave, placing it in warm water, leaving it in sunlight, or through any other method.

Always look at belimumab solution before you inject it. The solution should be clear to colorless or pale yellow. Do not use belimumab injection if it is cloudy, discolored, or has solid particles. Do not shake it.

You may inject belimumab injection on the front of the thighs or anywhere on your stomach except your navel (belly button) and the area 2 inches around it. Do not inject the medication into skin that is tender, bruised, red, hard, or not intact. Choose a different spot each time you inject the medication.

Belimumab injection given intravenously may cause serious reactions during and for up to a week after you receive the medication. A doctor or nurse will watch you closely during and after the intravenous infusion to be sure you are not having a serious reaction to the medication. You may be given other medications to treat or help prevent reactions to belimumab injection. Tell your doctor or nurse immediately if you experience any of the following symptoms: rash; itching; hives; swelling of the face, eyes, mouth, throat, tongue, or lips; difficulty breathing or swallowing; wheezing or shortness of breath; anxiousness; flushing; dizziness; fainting; headache; nausea; fever; chills; seizures; muscle aches; and slow heartbeat.

Belimumab helps control lupus but does not cure it. Your doctor will watch you carefully to see how well belimumab works for you. It may take some time before you feel the full benefit of belimumab. It is important to tell your doctor how you are feeling during your treatment.

Your doctor or pharmacist will give you the Medication Guide. Read the information carefully and ask your doctor or pharmacist if you have any questions

Are there OTHER USES for this medication?

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

What SPECIAL PRECAUTIONS should I follow?

Before using belimumab injection,

• tell your doctor or pharmacist if you are allergic to this drug, any part of this drug, or any other drugs, foods or substances. Tell your doctor or pharmacist about the allergy and what symptoms 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 taking belimumab. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• tell your doctor if you have an infection or if you have or have ever had an infection that keeps coming back, depression or thoughts of harming or killing yourself, or cancer.
• tell your doctor if you are pregnant or plan to become pregnant. It is not known if taking belimumab during pregnancy can harm your unborn baby. Your doctor may tell you that you should use effective birth control during your treatment with belimumab injection and for 4 months after your final dose. Talk to your doctor about birth control methods that you can use during your treatment. If you become pregnant during your treatment with belimumab injection, call your doctor.
• tell your doctor if you are breastfeeding.
• do not have any vaccinations without talking to your doctor. Tell your doctor if you have received a vaccine within the past 30 days.

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 an appointment to receive a belimumab infusion, call your doctor as soon as possible.

If you miss your subcutaneous dose of belimumab injection, inject the missed dose as soon as you remember it. Then, inject your next dose at your regularly scheduled time or continue weekly dosing based on the new day injected. Do not inject a double dose to make up for a missed one. Call your doctor or pharmacist if you need help to decide when to inject belimumab injection.

What SIDE EFFECTS can this medicine cause?

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

• nausea
• diarrhea
• headache or migraine
• redness, itching, swelling, pain, discoloration, or irritation at the injection site
• pain in the arms or legs
• runny nose

Some side effects can be serious. If you experience any of these symptoms or those listed in the HOW section, call your doctor immediately:

• fever, sore throat, chills, and other signs of infection; coughing up mucus; frequent, painful, or difficult urination; or warm; red, or painful skin or sores on your body
• thinking of harming or killing yourself or others, or planning or trying to do so; new or worsening depression or anxiety; difficulty falling asleep or staying asleep; unusual changes in your behavior or mood; or acting on dangerous impulses
• vision changes, memory loss, difficulty thinking clearly, difficulty talking or walking, or dizziness or loss of balance

Belimumab may increase your risk of certain cancers. Talk to your doctor about the risks of receiving this medication.

Belimumab may cause other side effects. Call your doctor if you have any unusual problems while using 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 (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

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 http://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 should I know about STORAGE and DISPOSAL of this medication?

Keep this medication in the package it came in, away from light, tightly closed, and out of reach of children. Do not shake autoinjectors or prefilled syringes that contains belimumab. Store belimumab injection in the refrigerator; do not freeze. Avoid exposure to heat. Syringes may be stored outside of the refrigerator (up to 30°C) for up to 12 hours if protected from sunlight. Do not use the syringes and do not place them back into the refrigerator if unrefrigerated for more than 12 hours. Discard any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

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. http://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 http://goo.gl/c4Rm4p for more information.

What OTHER INFORMATION should I know?

Keep all appointments with your doctor.

Ask your pharmacist any questions you have about belimumab injection.

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.

This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.

The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.

AHFS^® Patient Medication Information™ Copyright, 2025. The American Society of Health-System Pharmacists^®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: August 15, 2025.