I-131-bivatuzumab

I-131-A8 (also known as I-131-bivatuzumab or I-131-BIWA 8) is a radiopharmaceutical consisting of the humanized monoclonal antibody **bivatuzumab** labeled with the radioisotope **Iodine-131**. Bivatuzumab is designed to target the variant 6 isoform of CD44 (**CD44v6**), a cell surface glycoprotein that is overexpressed in various squamous cell carcinomas, particularly head and neck squamous cell carcinoma (HNSCC). The therapeutic strategy involves the antibody binding to CD44v6-positive tumor cells and delivering localized beta-radiation from the I-131 isotope, which induces DNA double-strand breaks and subsequent apoptosis. Developed by **Boehringer Ingelheim**, I-131-A8 reached Phase I/II clinical trials. However, the development of bivatuzumab-based therapies was halted due to severe and sometimes fatal skin toxicities, specifically toxic epidermal necrolysis (TEN), which resulted from the expression of CD44v6 in normal skin keratinocytes.

Other names

Iodine-131 bivatuzumabIodine131 bivatuzumabIodine 131 bivatuzumab131I-bivatuzumab131I-A8131I-BIWA 8I-131-labeled humanized monoclonal antibody A8I131-labeled humanized monoclonal antibody A8I 131-labeled humanized monoclonal antibody A8