Zr-89 durvalumab

**Zr-89 durvalumab** is a radiolabeled monoclonal antibody used for PET/CT imaging to non-invasively visualize and quantify tumor PD-L1 expression. It consists of the anti–PD-L1 antibody durvalumab conjugated to a chelator (DFO or DFOSq) and labeled with the positron-emitting radioisotope zirconium-89 (^89Zr^). The main clinical use is as a diagnostic radiopharmaceutical for immunoPET studies, principally in research settings to monitor PD-L1 status and potentially predict response to immune checkpoint inhibitor therapy in cancers such as recurrent or metastatic squamous cell carcinoma of the head and neck. The mechanism involves highly selective binding to PD-L1 (programmed death-ligand 1) on tumor and immune cells, allowing visualization via PET imaging. The drug does **not** itself treat cancer but enables molecular imaging for treatment planning and response prediction. Production for clinical use employs automated radiosynthesis to enhance reproducibility and operator safety[1][2][3].

Other names

Zr-89 durvalumabZr89 durvalumabZr 89 durvalumab89Zr-DFO-durvalumab[89Zr]Zr-DFOSq-durvalumab