131I-radretumab

131I-radretumab is a radiolabeled small immunoprotein format monoclonal antibody targeting the extra domain B (ED-B) of human fibronectin, developed by Philogen as a radioimmunotherapeutic for Hodgkin lymphoma, other hematologic malignancies, and solid-tumor brain metastases.[1][2][3][6] The L19 small immunoprotein moiety selectively binds ED-B fibronectin, which is minimally expressed in normal adult tissues but highly upregulated in angiogenic vasculature and remodeling extracellular matrix in tumors, enabling targeted delivery of the beta- and gamma-emitting radionuclide iodine-131 to neoplastic sites.[1][2][4] Through this mechanism, 131I-radretumab combines anti-angiogenic targeting with localized radiotoxicity to tumor-associated vasculature and adjacent tumor cells, and has shown selective tumor uptake and objective responses in phase I/II studies in relapsed lymphoma and in exploratory studies in patients with brain metastases from solid tumors.[1][2][3][7]

Brand names

radretumab

Other names

131I-radretumab131I-labeled L19SIP131I-L19-SIP