Update on the rational use of tositumomab and iodine-131 tositumomab radioimmunotherapy for the treatment of non-Hodgkin’s lymphoma

Targeted radioimmunotherapy in non-Hodgkin’s B-cell lymphoma (NHL) offers an efficacious therapy and minimal toxicity compared to conventional chemotherapy. Iodine 131 tositumomab ((131)I-TST) is a murine monoclonal antibody against the CD20 cell surface protein and is directly covalently conjugated to (131)I, a radioactive β and γ emitter. While initially approved for use in relapsed, refractory, or transformed low grade B-cell NHL, investigational uses with promising results include autologous stem cell transplant, intermediate grade NHL, and the frontline management of indolent NHL. This review summarizes the (131)I-TST literature on mechanism of action, treatment indications, treatment delivery, efficacy, investigational uses, and future prospects.