Usage
Basiliximab is prescribed for the prophylaxis of acute organ rejection in patients receiving renal transplantation. It is classified as an immunosuppressant. Specifically, it’s a chimeric (murine/human) monoclonal antibody. It works by binding to and blocking the interleukin-2 receptor alpha-chain (IL-2Rα, also known as CD25 antigen) on the surface of activated T-lymphocytes. This action inhibits IL-2 mediated T-cell activation and proliferation, crucial components of the immune response that leads to organ rejection.
Alternate Names
The international nonproprietary name is basiliximab. A popular brand name under which it is marketed is Simulect®.
How It Works
Pharmacodynamics: Basiliximab binds with high affinity to the IL-2Rα chain on activated T-lymphocytes. This prevents IL-2 from binding and triggering the cascade of intracellular signaling that leads to T-cell proliferation and activation, thereby suppressing the immune response directed towards the transplanted organ.
Pharmacokinetics: Following intravenous administration, basiliximab exhibits biphasic elimination. The initial phase is rapid, while the terminal phase is slower, with a half-life of approximately 7 days. The total body clearance is around 10-78 mL/h. Clearance can be reduced by concomitant administration of azathioprine or mycophenolate mofetil, but typically remains within the normal range. Basiliximab is primarily eliminated through hepatic metabolism, though other pathways might contribute.
Mode of Action: Basiliximab selectively targets the IL-2Rα chain, a component of the high-affinity IL-2 receptor expressed on activated T-lymphocytes. By occupying this receptor, basiliximab competitively inhibits the binding of IL-2, a key cytokine responsible for T-cell proliferation and differentiation. This targeted action disrupts the immune response directed at the allograft.
Receptor Binding/Enzyme Inhibition/Neurotransmitter Modulation: Basiliximab primarily acts through receptor binding (IL-2Rα). It does not directly inhibit enzymes or modulate neurotransmitters.
Elimination Pathways: Basiliximab is eliminated mainly via hepatic metabolism, potentially involving proteolytic degradation and other metabolic processes. Renal excretion plays a minor role.
Dosage
Standard Dosage
Adults:
20 mg IV within 2 hours before transplant surgery followed by a second 20 mg dose 4 days post-transplantation. The second dose should be withheld if severe hypersensitivity reactions or graft loss occur.
Children:
- <35 kg: 10 mg IV within 2 hours before transplant surgery, then 10 mg IV 4 days after transplantation.
- ≥35 kg: Same as adult dose (20 mg IV before surgery and 20 mg IV 4 days later).
- The second dose should be withheld if complications like severe hypersensitivity or graft loss occur.
Special Cases:
- Elderly Patients: No specific dosage adjustment is typically required based on age alone. However, consider age-related decline in organ function and overall health.
- Patients with Renal Impairment: No formal dose adjustment is recommended.
- Patients with Hepatic Dysfunction: No specific dosage adjustment is recommended.
- Patients with Comorbid Conditions: Careful monitoring and individualised treatment strategies are advised based on the specific comorbid conditions.
Clinical Use Cases
Basiliximab is exclusively used in renal transplantation for preventing allograft rejection and not indicated in other clinical settings. It is not suitable for the clinical situations you listed (intubation, surgical procedures, mechanical ventilation, ICU use, emergency situations).
Dosage Adjustments
No dose adjustments are needed when combined with cyclosporine, corticosteroids, and either azathioprine or mycophenolate mofetil. Caution is advised for patients with pre-existing hypersensitivity or prior exposure to basiliximab, due to the possibility of enhanced allergic reactions.
Side Effects
Common Side Effects:
Constipation, nausea, diarrhea, abdominal pain, headache, peripheral edema, hypertension, insomnia, infections (viral, bacterial, fungal), acne.
Rare but Serious Side Effects:
Severe acute hypersensitivity reactions (including anaphylaxis), cytokine release syndrome, opportunistic infections, lymphoproliferative disorders. Symptoms of these reactions might include dyspnea, wheezing, hypotension, tachycardia, rash, urticaria, pruritus, and angioedema.
Long-Term Effects:
Increased risk of infections and certain cancers due to immunosuppression.
Adverse Drug Reactions (ADR):
Anaphylaxis, cytokine release syndrome.
Contraindications
Known hypersensitivity to basiliximab or any component of the formulation. Pregnancy and lactation.
Drug Interactions
No dose adjustment is necessary when basiliximab is combined with cyclosporine, corticosteroids, and either azathioprine or mycophenolate mofetil. However, concomitant use with other immunosuppressants may increase the risk of infections and other immune-related complications. Live vaccines should be avoided during basiliximab treatment. Consult a comprehensive drug interaction database for detailed information on other potential drug interactions.
Pregnancy and Breastfeeding
Basiliximab is contraindicated in pregnancy and lactation due to its potential immunosuppressive effects on the fetus and neonate. Women of childbearing age should use reliable contraception during therapy and for 4 months after the last dose. Breastfeeding is not recommended during treatment and for 4 months following the last dose.
Drug Profile Summary
- Mechanism of Action: IL-2 receptor antagonist.
- Side Effects: Constipation, nausea, infections, hypersensitivity reactions (including anaphylaxis).
- Contraindications: Hypersensitivity to basiliximab, pregnancy, breastfeeding.
- Drug Interactions: Other immunosuppressants, live vaccines.
- Pregnancy & Breastfeeding: Contraindicated.
- Dosage: Adults: 20 mg IV before transplant and 20 mg IV 4 days later. Children: Dose depends on weight.
- Monitoring Parameters: Renal function, signs of infection, hypersensitivity reactions.
Popular Combinations
Basiliximab is typically used in combination with cyclosporine, corticosteroids, and either azathioprine or mycophenolate mofetil in renal transplantation. This combination provides synergistic immunosuppression for preventing allograft rejection.
Precautions
- General Precautions: Monitor for hypersensitivity reactions, infections, and lymphoproliferative disorders.
- Specific Populations: Avoid in pregnancy and breastfeeding. Exercise caution in patients with prior exposure to basiliximab.
- Lifestyle Considerations: No specific lifestyle considerations, but general health advice for transplant recipients applies.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Basiliximab?
A: Adults: 20 mg IV before transplant surgery and another 20 mg IV 4 days later. Children <35 kg: 10 mg IV before surgery and 10 mg IV 4 days later. Children ≥35 kg: Same as adult dose.
Q2: What is the mechanism of action of Basiliximab?
A: Basiliximab is an IL-2 receptor antagonist that binds to the IL-2Rα chain on activated T-lymphocytes, inhibiting IL-2 mediated T-cell activation and proliferation.
Q3: What are the main side effects of Basiliximab?
A: Common side effects include constipation, nausea, diarrhea, infections, and headache. Serious side effects include hypersensitivity reactions (anaphylaxis) and opportunistic infections.
Q4: Is Basiliximab safe during pregnancy and breastfeeding?
A: No, Basiliximab is contraindicated during pregnancy and breastfeeding due to potential risks to the fetus/infant.
Q5: What are the contraindications for Basiliximab?
A: Known hypersensitivity to basiliximab and pregnancy/breastfeeding.
Q6: How is Basiliximab administered?
A: Basiliximab is administered intravenously, either as a bolus injection or as an infusion over 20-30 minutes.
Q7: What drugs does Basiliximab interact with?
A: Basiliximab’s clearance can be affected by azathioprine and mycophenolate mofetil, although dose adjustments are usually not necessary. Concomitant use with other immunosuppressants increases the risk of infections. Live vaccines should be avoided.
Q8: What should be monitored in patients receiving Basiliximab?
A: Monitor renal function, signs and symptoms of infection, and any potential hypersensitivity reactions.
Q9: Can Basiliximab be used in patients with hepatic or renal impairment?
A: While no specific dosage adjustments are recommended, caution is advised, and patients should be monitored closely.
Q10: What is the role of Basiliximab in organ transplantation?
A: Basiliximab is used to prevent acute organ rejection in renal transplant recipients.
