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Belimumab is a biologic medication used to treat adults with lupus (systemic lupus erythematosus, also called SLE).

  • What types of arthritis is belimumab used for?

    Belimumab is a biologic medication used to treat adults with lupus (systemic lupus erythematosus, also called SLE). Belimumab is generally reserved for patients who cannot tolerate or have failed traditional SLE therapies.
    People with active lupus often have high levels of a protein called BLyS in their blood, which turns on special immune cells called B cells.  The abnormal activity of B cells in lupus may lead to damage affecting multiple organs.  Belimumab blocks the activity of BLyS.

    Safety and effectiveness has not been assessed in patients with severe active lupus nephritis or central nervous system lupus.

  • How is belimumab administered?

    Belimumab is given by subcutaneous (s.c.) injection (meaning in the fatty layer of tissue just under the skin).  Belimumab may be also given by infusion to treat SLE. 

  • What is the typical dose and when do I take it?

    When given by infusion the dose of belimumab is based on your weight. Belimumab infusions are given every 2 weeks for 3 doses, and then every 4 weeks. Each infusion takes about 60 minutes.
    Prior to each infusion, treatment with acetaminophen and an antihistamine (e.g., diphenhydramine) are given to prevent an allergic reaction during the infusion.
    When given by s.c. injection the dose of belimumab is 200 mg given once weekly in the abdomen or thigh (on the same day each week). The medication comes as a single-use pre-filled syringe or single-use autoinjector for subcutaneous administration.
    The first s.c. injection of belimumab should be under the supervision and direction of a healthcare professional. After an initial training in proper s.c. injection technique and education about signs and symptoms of allergic reactions, you or your caregiver may self-inject belimumab if your healthcare provider determines that it is appropriate for you.

    Prior to each s.c. injection of belimumab, it should be removed from the refrigerator and allowed to sit at room temperature for 30 minutes. Do not warm belimumab in any other way.
    Belimumab pre-filled syringes and auto-injectors cannot be used for infusions. Single-use vials for infusions cannot be used for s.c. injections.

  • How long will it take to work?

    Like all of the biologics, you will not feel the effects of belimumab right away. Some people begin to feel the effects of belimumab within a few weeks; however, it may take three to four months to feel the full effect. It is important to be patient and keep taking your medication.

  • When should I not take belimumab and call my doctor?

    Belimumab can make it harder for your body to fight infections. Therefore, if you have a fever, think you may have an infection or have been prescribed an antibiotic, contact your healthcare provider immediately. Also, contact your prescriber if you are having surgery, as you may need to stop belimumab until you are healed and there is no sign of infection.
    Before taking belimumab, tell your healthcare provider if you are pregnant or planning to become pregnant or are breastfeeding or planning to breastfeed. Currently there are no studies to assess the use of belimumab during pregnancy and breastfeeding.  Your healthcare provider will discuss the risks and benefits of taking belimumab while you are pregnant.
    Ideally, your vaccinations should be up to date prior to starting belimumab. If you have already started therapy with belimumab, most inactive vaccines are recommended (i.e. influenza, pneumococcal). Live vaccines are not recommended due to risk of causing infection.
    Anyone who has had a previous allergic reaction to belimumab should avoid the medication.
    Belimumab has been very rarely associated with a small increased risk of developing certain types of cancer. The role of belimumab in the development of cancer is currently unknown.  Please speak with your healthcare provider if you have any questions.

  • What are the side effects of belimumab?

    Like all medications, taking belimumab carries some risk of side effects, which must be balanced with the potential benefits. When monitored properly the vast majority of side effects are rare, most improve over time and are reversible.

    Some people experience headaches, nausea, or diarrhea with belimumab. If any of these symptoms become severe, please speak with your healthcare provider.

    Belimumab can rarely cause an allergic reaction during the infusion (flushing, itching, changes in heart rate and blood pressure, etc.).  A healthcare professional will monitor for this reaction during the infusion and give you medication prior to the infusion to help prevent the reaction.

    Depression, suicidal thoughts or behavior, and self-injury have been very rarely reported in patients with SLE receiving belimumab.  Discuss these risks with your healthcare provider prior to starting belimumab.  Contact your healthcare provider if you experience worsening depression or thoughts of suicide while taking belimumab.

  • What helps to reduce side effects?

    Take your belimumab as prescribed and contact your healthcare provider if you have any concerns while taking the medication.

  • Do I need any monitoring while taking belimumab?

    Your healthcare provider may order periodic blood tests to check your blood counts and to follow the activity of your SLE.

This information was last updated January 2020, with expert advice from:

Jason Kielly, B.Sc. (Pharm.), Pharm.D.
Associate Professor, School of Pharmacy, Memorial University of Newfoundland
Clinical Pharmacist, Rheumatic Health Program, Eastern Health

Hamidreza Izadpanah , Pharm.D.

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