title: Additional radiation absorbed dose estimates for Zevalin radioimmunotherapy.
abstract: Zevalin (ibritumomab tiuxetan) radioimmunotherapy is a novel treatment for non-Hodgkin's lymphoma (NHL). The Zevalin regimen includes 5 mCi (111)In-labeled Zevalin on Day 1, followed by serial anterior and posterior planar gamma images for imaging or dosimetry. On Day 8, patients receive 0.4 mCi/kg (90)Y Zevalin for radioimmunotherapy. Both Zevalin doses are preceded by 250 mg/m(2) rituximab to clear peripheral B cells and improve biodistribution of the radiolabeled antibody. In a 143-patient, Phase III, randomized study, the Zevalin regimen produced a significantly higher overall response rate than rituximab for relapsed or refractory, low-grade, follicular, or transformed NHL (80% versus 56%, p = 0.02). Fifteen patients from the Zevalin arm of this study were randomly selected for additional radiation dosimetry. (90)Y residence times were calculated from (111)In image analysis data. MIRDOSE3.1 radiation absorbed dose estimates to normal tissues were highest for spleen, testes, and liver, with considerably lower doses reaching heart, lung, intestines, red marrow, and kidneys. Radiation absorbed doses to organs and marrow were within a safe range following administration of 0.4 mCi/kg (90)Y Zevalin.
authors.affiliation: Mayo Clinic, Rochester, MN 55905, USA. gwiseman@mayo.edu
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Wiseman
authors.forename: Bryan R
authors.initials: BR
authors.lastname: Leigh
authors.forename: William L
authors.initials: WL
authors.lastname: Dunn
authors.forename: Michael G
authors.initials: MG
authors.lastname: Stabin
authors.forename: Christine A
authors.initials: CA
authors.lastname: White
mesh_terms: D000911:Antibodies, Monoclonal / Q000008:administration & dosage* / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use; D058846:Antibodies, Monoclonal, Murine-Derived; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use; D003131:Combined Modality Therapy; D004307:Dose-Response Relationship, Radiation; D019008:Drug Resistance, Neoplasm; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000532:radiotherapy*; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000532:radiotherapy*; D011446:Prospective Studies; D016499:Radioimmunotherapy; D000069283:Rituximab; D016879:Salvage Therapy; D014018:Tissue Distribution; D014055:Tomography, Emission-Computed; D016896:Treatment Outcome; D015021:Yttrium Radioisotopes / Q000627:therapeutic use
chemical_list: D000911:Antibodies, Monoclonal; D058846:Antibodies, Monoclonal, Murine-Derived; D000970:Antineoplastic Agents; D015021:Yttrium Radioisotopes; D000069283:Rituximab; C422802:ibritumomab tiuxetan