Memorial for a radiopharmaceutical—Azedra or no-carrier-added [ ¹³¹ I]-MIBG

Azedra is the name given to high specific activity/high molar activity MIBG ( m-[ 131 I]-(iodobenzylguanindinium)), iobenguane ( 131 I) produced commercially for the treatment of adrenal carcinoma: neuroblastoma, pheochromocytoma, and paraganglioma. Azedra was patented in 2007; human clinical testing began in 2009 and the drug was approved by the FDA in 2018 and discontinued in 2024. Herein, we describe the lifeline of Azedra from concept to its discontinuation as an example of the challenges involved in the development, production, and distribution of a radiopharmaceutical.