Radioimmunotherapy: from current clinical success to future industrial breakthrough?

Radioimmunotherapy is a targeted molecular therapy that bears on radiobiologic and immunologic processes, without crossresistance with other anticancer cytotoxic drugs. Since the first reports in the literature at the beginning of the 1980s, radioimmunotherapy techniques have significantly progressed because of advancements in recombinant humanized or human monoclonal antibodies, the synthesis of more stable chelates for radiolabeling, and pretargeting techniques that increase the therapeutic index. Several pivotal clinical studies demonstrated the efficacy of radioimmunotherapy in non-Hodgkin B-cell lymphoma (NHL), and 2 radioimmunotherapy-products targeting the CD20 antigen have been approved: 131I-tositumomab (Bexxar; GlaxoSmithKline) and 90Yibritumomab tiuxetan (Zevalin; Spectrum Pharmaceuticals). The marketing of 131I-tositumomab is now discontinued. 90Y-ibritumumab can be integrated in clinical practice using nonablative activities for the treatment of relapsed or refractory follicular lymphoma