iodine I 131 tositumomab (I-oh-dine I 131 TAH-sih-TOO-moh-mab)
A drug used with another drug to treat certain types of B-cell non-Hodgkin lymphoma. It is also being studied in the treatment of other types of cancer. Iodine I 131 tositumomab is a form of the monoclonal antibody tositumomab that is linked to the radioactive substance iodine I 131. It is a type of radioimmunoconjugate.