Iodine I-131 tositumomab

Iodine I-131 tositumomab (Bexxar) is a CD20-directed radioimmunotherapy consisting of a murine IgG2a monoclonal antibody (tositumomab) covalently linked to the radioactive isotope iodine-131. Developed by Corixa and later acquired by GSK, this biologic therapeutic regimen was FDA-approved in 2003 for the treatment of patients with CD20-positive, relapsed or refractory, low-grade, follicular, or transformed non-Hodgkin's lymphoma, including those with rituximab-refractory disease. The treatment involves a two-step process: a dosimetric dose to calculate patient-specific radiation delivery, followed one week later by a therapeutic dose designed to deliver targeted beta and gamma radiation to tumor cells while minimizing exposure to normal tissues. GSK discontinued the manufacture and sale of Bexxar in February 2014 due to low clinical usage.

Brand names

Bexxar

Other names

I-131 tositumomabI131 tositumomabI 131 tositumomabtositumomab and iodine I 131 tositumomab