Home Drug Guide Ibritumomab Tiuxetan

Drug Guide

Generic Name

Ibritumomab Tiuxetan

Brand Names Zevalin

Classification

Therapeutic: Antineoplastic agent, immunotherapy

Pharmacological: Monoclonal antibody targeting CD20

FDA Approved Indications

Treatment of relapsed or refractory follicular non-Hodgkin's lymphoma (NHL)

Mechanism of Action

Ibritumomab binds to the CD20 antigen on B lymphocytes, and when conjugated with the radioisotope yttrium-90, it delivers targeted radiotherapy to malignant B cells, leading to cell death.

Dosage and Administration

Adult: Initial dose of 0.4 mCi (14.8 MBq) for each of the first 2 doses, administered intravenously over 10 to 30 minutes, with a 7-day interval between doses. Pre-treatment with rituximab is recommended.

Pediatric: Not approved for pediatric use.

Geriatric: Similar dosing as adults; monitor renal and hepatic function.

Renal Impairment: Adjustment not specified; use caution and monitor renal function.

Hepatic Impairment: Adjustment not specified; use caution and monitor hepatic function.

Pharmacokinetics

Absorption: Administered intravenously, no oral absorption.

Distribution: Binds to CD20-positive B cells, localized primarily to lymphoid tissues.

Metabolism: Catabolized by cellular processes similar to other antibodies.

Excretion: Renal and hepatic clearance of breakdown products.

Half Life: Approximately 36 hours for the antibody component.

Contraindications

Hypersensitivity to ibritumomab or murine proteins.
Active infections.

Precautions

Use in patients with compromised immune systems.
Pre-treatment with rituximab reduces circulating B cells, increasing infection risk. Risk of myelosuppression, tumor lysis syndrome, and infusion reactions.

Adverse Reactions - Common

neutropenia (Common)
thrombocytopenia (Common)
anemia (Common)
infusion reactions (Common)

Adverse Reactions - Serious

tumor lysis syndrome (Serious but less common)
severe cytopenias (Serious)
febrile neutropenia (Serious)

Drug-Drug Interactions

Other myelosuppressive agents
Immunosuppressants

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor blood counts regularly; assess for infusion reactions; evaluate for signs of infection or bleeding.

Diagnoses:

Risk for infection
Impaired tissue perfusion related to cytopenias

Implementation: Administer premedications as per protocol; observe during and after infusion; monitor blood counts and vital signs.

Evaluation: Ensure blood counts recover; monitor for adverse reactions and effectiveness.

Patient/Family Teaching

Report any signs of infection, fever, bleeding, or unusual symptoms immediately.
Follow guidelines for infection prevention.
Avoid live vaccines during and for a period after treatment.

Special Considerations

Black Box Warnings:

Severe infusion reactions, tumor lysis syndrome, and myelosuppression.

Genetic Factors: None specific.

Lab Test Interference: May cause lymphopenia and cytopenias, affecting laboratory results.

Overdose Management

Signs/Symptoms: Severe cytopenias, infusion reactions.

Treatment: Supportive care, blood transfusions if needed, corticosteroids, and interventions for tumor lysis syndrome.

Storage and Handling

Storage: Refrigerate at 2°C to 8°C (36°F to 46°F).

Stability: Stable until the expiration date on the package when stored properly.