Belimumab is a recently developed monoclonal antibody drug used to treat systemic lupus erythematosus, otherwise known as SLE or just lupus. Lupus is an autoimmune disorder that involves B-cell overactivation, causing patient’s own immune system to attack them and results in symptoms such as rash, fever, chest pain, hair loss, joint pain, and fatigue. Monoclonal antibodies are synthetic antibodies produced in a lab that will act against certain proteins in people with autoimmune disorders to inhibit a particular response. These manmade antibodies can be specifically designed to target different proteins in the human body that may be the source of permanent overactivation of the immune system. In the case of SLE, patients with B-cell protein markers are readily able to take belimumab because this marker allows for the monoclonal antibody to prevent autoimmune responses.
Monoclonal antibodies such as belimumab are an important method of treatment in patients with SLE because they block the action of B-cell stimulator protein, which B-cells require for survival. When the patient is introduced to belimumab, the drug inhibits the B-cell stimulator protein, which causes B-cell death and prevents an ongoing autoimmune adaptive response, including the release of inflammatory cytokines. This causes a depression in the activity of the acquired immune system and its responses, meaning patients with SLE will experience relief from autoimmune symptoms. The purpose of this drug it to prevent the painful symptoms that may arise from SLE flare-ups. Although this drug is designed to help prevent the signs and symptoms of SLE, there is a large list of side effects, including:
- nausea
- diarrhea
- vomiting
- stomach pain
- fever
- stuffy or runny nose
- cough (bronchitis)
- insomnia
- leg or arm pain
- migraine
- sore throat
- allergic or infusion-related reactions such as
- itching
- swelling of the face, lips, tongue, mouth, or throat
- difficulty breathing
- low blood pressure
- dizziness
- fainting
- rash
- redness
- swelling of the skin
When considering these side effects, there are quite a few differences between these and the symptoms of SLE. Belimumab seems to have more side effects than the symptoms of SLE itself, but these side effects are often temporary and not chronic. SLE has chronic, debilitating symptoms that may make it worth looking into a treatment such as belimumab. However, it is important to note that patients may experience more severe side effects from belimumab, such as infections, heart problems, depression, and elevated risk for cancer.
There are many different aspects of health that need to be considered before taking belimumab. Patients receiving this treatment may not receive live vaccinations because this drug decreases the adaptive immune response, making the exposure to live pathogens dangerous. Patients may also not be pregnant, because the effects of belimumab on an unborn baby have not yet been thoroughly studied. Additionally, patients with previous mental health issues may not be prescribed this medication because of the increased risk of depression associated with this drug. Overall, this monoclonal antibody treatment is an excellent way to prevent SLE flare-ups, but may lead to more serious side effects if patients are not responsive to the treatment.

