CBO-003

CBO-003 is a nanobody-radionuclide conjugate (NRC) being developed by CIS BIOPHARMA for the treatment of glioblastoma multiforme (GBM). It functions as a radioligand therapy (RLT) by utilizing a nanobody to specifically target CD276 (also known as B7-H3), an immune checkpoint protein that is frequently overexpressed in various solid tumors, including GBM. By binding to CD276-expressing cells, CBO-003 delivers a radioactive isotope payload directly to the tumor site, inducing targeted cell death through ionizing radiation while minimizing damage to surrounding healthy tissue. As of early 2024, the drug is in the preclinical stage of development.