Nurses Compass
Drug Guide
Belimumab
Classification
Therapeutic: Immunosuppressant, Monoclonal Antibody
Pharmacological: Anti-BAFF (B-cell activating factor)
FDA Approved Indications
- Treatment of *Systemic Lupus Erythematosus (SLE)* in adult patients with active, autoantibody-positive disease
Mechanism of Action
Belimumab binds to soluble B-lymphocyte stimulator (BLyS), preventing it from activating B cells, thereby reducing B cell survival and differentiation that contributes to SLE pathogenesis.
Dosage and Administration
Adult: 10 mg/kg IV infusion given over 1 hour on days 1, 15, 29, and then every 4 weeks.
Pediatric: Not approved for pediatric use.
Geriatric: No specific dosage adjustment, but caution in elderly due to potential comorbidities.
Renal Impairment: No dosage adjustment necessary.
Hepatic Impairment: No specific data, use with caution.
Pharmacokinetics
Absorption: Not applicable (IV infusion).
Distribution: Vd approximately 7.4 L.
Metabolism: Degraded by proteolytic enzymes.
Excretion: Eliminated via catabolism; not excreted unchanged in urine.
Half Life: Approximately 19 days.
Contraindications
- Hypersensitivity to belimumab or any component of the formulation.
Precautions
- Use with caution in patients with active infections; monitor for infusion reactions; assess risk of immunosuppression.
Adverse Reactions - Common
- Nausea (Common)
- Diarrhea (Common)
- Fever (Common)
- Infusion reactions (e.g., infusion site reactions, rash) (Common)
Adverse Reactions - Serious
- Serious infections (e.g., bacterial, viral, fungal) (Less common)
- Hypersensitivity reactions including anaphylaxis (Rare)
- Progressive multifocal leukoencephalopathy (PML) (Very rare)
Drug-Drug Interactions
- Other immunosuppressants (risk of increased immunosuppression)
Drug-Food Interactions
- No significant interactions reported.
Drug-Herb Interactions
- Limited data; caution advised with herbal supplements that affect immune system.
Nursing Implications
Assessment: Monitor patient for signs of infection, infusion reactions, and allergic reactions.
Diagnoses:
- Risk for infection,
Implementation: Administer IV infusion as prescribed; premedicate if necessary to reduce infusion reactions.
Evaluation: Assess effectiveness by monitoring disease activity and B-cell counts; monitor for adverse reactions.
Patient/Family Teaching
- Report symptoms of infection immediately.
- Understand the importance of regular follow-up and blood tests.
- Be aware of potential infusion reactions and seek medical attention if they occur.
Special Considerations
Black Box Warnings:
- Serious infections, including tuberculosis and fungal infections.
- Progressive multifocal leukoencephalopathy (PML).
Genetic Factors: No specific genetic testing recommended.
Lab Test Interference: Potential alteration of serum B-cell levels; routine lab tests may be affected.
Overdose Management
Signs/Symptoms: Unusual infusion reactions, hypersensitivity.
Treatment: Discontinue infusion, provide supportive care, and monitor.
Storage and Handling
Storage: Refrigerate between 2°C and 8°C; do not freeze.
Stability: Stable for 24 hours at room temperature (not exceeding 25°C) once prepared for infusion.