Radionuclide

  • 111In: t1/2: 2.8 d
    Energies: 173, 247 keV
    Type: EC, γ, accelerator
  • 90Y: t1/2: 64.1 h
    Energies: 2.284 MeV
    Type: β, fission product

Radiopharmaceutical

  • 111In-chloride: Isothiocyanatobenzyl-derivatized DTPA linker, Ibritumomab (intact IgG1 kappa murine monoclonal antibodies
    [Moabs]), and tiuxetan, MX-DTPA. Zevalin®
  • 90Y-chloride: Same. Zevalin®. 90Y beta particles travel about 5 mm in soft tissue (100–200 cell diameters)

Localization

  • Compartmental, blood flow; dose dependent, antibody binding. Targets CD20 antigen located on the normal and malignant B-lymphocytes of non-Hodgkin’s lymphoma (NHL).

Quality Control

  • If made from kit, chromatography, ≥ 95% radiochemical purity for both. Store in refrigerator before use.
  • 111In: Use within 12 hours.
  • 90Y: Use within 8 hours.

Adult Dose Range

  • 111In: 5 mCi (185 MBq)
  • 90Y: .4 mCi/kg (14.8 MBq/kg) for therapy, not to exceed 32 mCi (1184 MBq)

Method of Administration

  • Intravenous butterfly (large bore, 18–22 ga.) over 10 minutes with a .2-um micropore filter on the syringe.
  • 10-mL saline flush.
  • Should have physician or nurse available for possible allergic reaction (1 mg epinephrine available).
  • Follow vital signs: Baseline, 5 minutes postinjection, 15, 30, and 60 minutes. (Some simply observe patient for 15 minutes looking for redness at injection site or signs of nausea and vomiting.)

Indications

  • Confirm biodistribution of 111In-Zevalin® for 90Y-Zevalin® therapy.
  • Treatment of patients with relapsed or refractory low grade, follicular or transformed B-cell non-Hodgkin’s lymphoma.
  • Treatment of patients includes Rituxan (rituximab)-refractory follicular NHL.

Contraindications

  • Patients with known Type 1 hypersensitivity or anaphylactic reactions to murine proteins or any component of this product, including but not limited to yttrium chloride and indium chloride.
  • Patients with ≥ 25% lymphoma marrow involvement and/or impaired bone marrow reserve caused by myeloablative surgery, low platelet counts, neutrophil count < 1500 cells/mL.
  • Patients having bone marrow transplantation or radioimmunotherapy.
  • Patients with leukemia, HIV, or AIDS.
  • 90Y-Zevalin® should not be administered to patients with platelet counts < 100,000/mm3. If counts are 100,000 to 149,000/mm3, activity should be adjusted to .3 mCi/kg (11.1 MBq/kg).
  • 90Y-Zevalin® should not be administered to patients with altered biodistribution as determined by the outcome of the 111In-Zevalin® images.

Patient Preparation

  • Identify the patient. Verify doctor’s order. Explain the procedure.
  • Obtain a signed consent form from patient for the 90Y therapy.
  • Obtain appropriate written directive for therapy dosage.
  • Ensure patient supplies list of history of allergies and prior exams.
  • Female patients of childbearing age should be advised to avoid becoming pregnant during therapy. Pregnant females should be counseled as to the potential hazard to the fetus.
  • Patients who have had a previous Moab test should have a HAMA titer (human anti-mouse antibody) performed before another injection.
  • Verify patient’s platelet count. For 90Y, not less than 100,000/mm3.
  • Patient to receive Rituxan (cold ibritumomab) therapy at physician’s office 4 hours before receiving the 111In dosage and again before the 90Y therapy dose.
  • Patient should be well hydrated before 111In and 90Y dosing.