I-131 tositumomab.

IMPORTANCE OF THE FIELD: Follicular lymphoma (FL) is a subgroup of B-cell Non-Hodgkin's lymphomas (NHL) that account for 15 - 30% of all lymphomas. I-131 tositumomab is a radiommunoconjugate of (131)I and the anti-CD20 monoclonal antibody tositumomab. It is one of two available radioimmunoconjugates for the treatment of recurrent, refractory, or transformed FL. AREAS COVERED IN THIS REVIEW: This review describes the clinical pharmacology of I-131 tositumomab, dosing and administration guidelines, and the key clinical trials providing evidence of its efficacy and safety in patients with FL, transformed, or other aggressive B-NHL, in combination with chemotherapy, or its incorporation in transplant conditioning regimens. This review also covers safety and regulatory concerns regarding the use of I-131 tositumomab. WHAT THE READER WILL GAIN: This review critically appraises the clinical trials behind approval of I-131 tositumomab as a second-line agent for FL and also outlines the data supporting its use in the upfront setting. TAKE HOME MESSAGE: I-131 tositumomab is a safe and effective option for patients with recurrent, refractory, or transformed FL and carries promise in the upfront treatment of FL, aggressive B-NHL, and as a transplant conditioning regimen.