Generic Name

Siltuximab

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Classification

FDA Approved Indications

• Castleman's Disease (multicentric, HIV-negative, HHV-8-negative)

Mechanism of Action

Siltuximab binds to interleukin-6 (IL-6), preventing IL-6 from interacting with its receptor, thereby reducing inflammatory responses and tumor growth associated with cytokine-driven diseases.

Dosage and Administration

Adult: At presentation, 11 mg/kg IV every 3 weeks. Dose adjustments are not typically required. Pre-medication with antihistamines and corticosteroids is recommended to reduce infusion-related reactions.

Pediatric: Not approved for pediatric use; safety and efficacy not established.

Geriatric: No specific dosage adjustments required based on age.

Renal Impairment: No specific data; use with caution and monitor closely.

Hepatic Impairment: No specific data; use with caution, considering liver function tests.

Pharmacokinetics

Absorption: Administered IV; absorption not applicable.

Distribution: Distributed mainly in the vascular and extravascular compartments.

Metabolism: Metabolized via proteolytic pathways like other monoclonal antibodies.

Excretion: Primarily degraded into peptides and amino acids; not excreted renally.

Half Life: Approximately 16-18 days.

Contraindications

• Hypersensitivity to siltuximab or other components.

Precautions

• Monitor for infusion reactions, cytopenias, infections, and gastrointestinal perforation. Use caution in patients with active infections or immunosuppression.

Adverse Reactions - Common

• Infections (e.g., upper respiratory, urinary tract) (Common)
• Infusion reactions (fever, chills, rash) (Common)
• Fatigue, nausea, headache (Common)

Adverse Reactions - Serious

• Serious infections including sepsis (Less common)
• Gastrointestinal perforation (Rare)
• Hypersensitivity reactions (Rare)

Drug-Drug Interactions

• No significant direct interactions reported; caution when used with other immunosuppressants.

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Patient/Family Teaching

• Report any signs of infection immediately.
• Inform about possible infusion reactions.
• Discuss importance of adhering to scheduled treatments and monitoring.
• Advise on warning signs such as fever, rash, or difficulty breathing.

Special Considerations

Black Box Warnings:

• Serious infections, including sepsis, can be life-threatening.
• Gastrointestinal perforation has been reported.

Genetic Factors: No specific genetic testing required.

Lab Test Interference: None documented.

Overdose Management

Signs/Symptoms: Potential for immune-related adverse effects, severe infusion reactions, or infections.

Treatment: Supportive care, discontinuation of drug, and symptomatic treatment as needed.

Storage and Handling

Storage: Store refrigerated at 2-8°C (36-46°F). Protect from light.

Stability: Product stability and expiry date provided on the packaging.