Basiliximab
Introduction to Basiliximab
Basiliximab (trade name: Simulect) is a chimeric monoclonal antibody that functions as an immunosuppressant drug. Approved by the FDA in 1998, it has become a cornerstone in preventing acute organ rejection in pediatric renal transplant recipients.
Key features:
- Composition: 75% human and 25% murine protein sequences
- Target: Interleukin-2 receptor α-chain (CD25) on activated T-lymphocytes
- Half-life: Approximately 7 days in adults, potentially shorter in children
- Elimination: Primarily via intracellular catabolism following endocytosis
Mechanism of Action
Basiliximab's immunosuppressive effect is achieved through:
- Selective binding to CD25 on activated T-lymphocytes
- Inhibition of IL-2-mediated T-cell proliferation and differentiation
- Suppression of cytokine production, including interferon-γ and tumor necrosis factor-α
- Reduction in circulating CD3+ and CD4+ T-cells
This targeted approach allows for effective immunosuppression while minimizing systemic effects compared to broader immunosuppressive agents.
Indications
Primary indications for basiliximab in pediatric patients:
- Prevention of acute organ rejection in renal transplantation
- Induction therapy in high-risk kidney transplant recipients
- Component of steroid-sparing immunosuppressive regimens
Emerging off-label uses in pediatrics:
- Treatment of steroid-resistant graft-versus-host disease
- Management of severe, treatment-refractory atopic dermatitis
- Adjunctive therapy in pediatric heart transplantation
Dosage and Administration
Basiliximab is administered intravenously as two doses:
| Patient Weight | Dose | Timing |
|---|---|---|
| < 35 kg | 10 mg per dose | 1st dose: Within 2 hours pre-transplant 2nd dose: 4 days post-transplant |
| ≥ 35 kg | 20 mg per dose | 1st dose: Within 2 hours pre-transplant 2nd dose: 4 days post-transplant |
Administration guidelines:
- Reconstitute with 10 mL sterile water for injection
- Dilute to 50 mL with normal saline or dextrose 5% in water
- Administer over 20-30 minutes
- Do not administer concomitantly with other medications
Adverse Effects
Common adverse reactions (incidence ≥ 10%):
- Gastrointestinal: constipation (38%), nausea (25%), abdominal pain (17%), vomiting (12%)
- Metabolic: hyperkalemia (17%), hypokalemia (13%), hyperglycemia (12%)
- Genitourinary: urinary tract infection (14%)
- Cardiovascular: hypertension (13%)
- Hematologic: anemia (11%)
Severe adverse events (rare but significant):
- Cytokine release syndrome (<1%)
- Severe hypersensitivity reactions, including anaphylaxis (<1%)
- Post-transplant lymphoproliferative disorder (1-2% in pediatric patients)
- Opportunistic infections (incidence varies)
Precautions and Contraindications
Contraindications:
- Known hypersensitivity to basiliximab or any component of the formulation
- Previous anaphylactic reaction to basiliximab
Precautions:
- Live vaccines: Avoid administration of live vaccines for at least 2 months post-treatment
- Pregnancy: Limited data available; use only if potential benefit justifies potential fetal risk
- Lactation: No data on presence in human milk; consider developmental and health benefits of breastfeeding
- Pediatric use: Safety and efficacy established in patients 1 year and older; limited data in infants <1 year
Clinical Pearls
- Basiliximab does not require therapeutic drug monitoring, simplifying its use in pediatric patients
- The immunosuppressive effect of basiliximab can last for 4-6 weeks post-administration
- Concurrent use with other T-cell antibodies (e.g., anti-thymocyte globulin) may increase the risk of over-immunosuppression
- In pediatric patients, basiliximab has been associated with a reduced need for corticosteroids, potentially mitigating growth-related side effects
- The risk of post-transplant lymphoproliferative disorder may be higher in EBV-seronegative pediatric recipients
