Ibritumomab Tiuxetan Injection

• Type: Radioimmunotherapy agent

• Drug Class: Monoclonal antibody + radioisotope conjugate

• Form: Sterile solution for intravenous (IV) infusion

How It Works

• Ibritumomab is a monoclonal antibody that specifically targets CD20 antigen found on B-lymphocytes (normal and malignant).

• It is chemically linked to tiuxetan, which carries the radioactive isotope Yttrium-90 (Y-90).

• This combination delivers targeted radiation directly to B-cells, killing them and nearby cancerous cells through radiation-induced damage.

Common Uses

Ibritumomab Tiuxetan is used mainly for:

• Relapsed or refractory low-grade, follicular, or transformed B-cell non-Hodgkin’s lymphoma (NHL)

• Sometimes as consolidation therapy after initial chemotherapy to prolong remission

Administration

• Given as a two-step regimen:

  1. Rituximab infusion (to clear circulating B-cells and allow better targeting)

  2. Ibritumomab Tiuxetan infusion (with Y-90 radioisotope)

• Administered under strict hospital supervision with radiation safety precautions

Advantages

• Provides a targeted approach, minimizing systemic toxicity

• Effective even in patients who no longer respond to chemotherapy

• Short treatment course (typically one week) compared to prolonged chemo cycles

Possible Side Effects

Common:

• Low blood cell counts (neutropenia, thrombocytopenia)

• Fatigue, weakness

• Mild infusion-related reactions (fever, chills)

Less Common but Serious:

• Severe, prolonged cytopenias (risk of infection and bleeding)

• Secondary malignancies (very rare, long-term risk)

• Allergic or hypersensitivity reactions

• Radiation-related effects

Precautions

• Blood counts must be monitored before, during, and after therapy

• Avoid in patients with severely low platelet counts or bone marrow involvement >25%

• Radiation precautions may be advised for a short period after treatment

• Not recommended during pregnancy or breastfeeding due to radiation risk