IDEA #855PI6 Novel reagent and bifunctional chelators for the site-selective radiolabeling of proteins and peptides with Zr89 and Lu177. 17A0041

The purpose of these molecules (PODS and bifunctional chelators ─ PODS-DFO and PODS-ChxA-DTPA) are to allow the site-selective or site-specific conjugation of proteins and peptides though naturally occurring cysteines or engineered cysteines. Indeed, several studies have demonstrated the superiority of the site-specific conjugation over the random conjugation, in terms of in vivo behavior and pharmacokinetics. The PODS reagent can be appended by numerous cargo through its terminal primary amine, allowing conjugation of that cargo to the biomolecule (proof of concept with fluorescein), while the bifunctional chelators PODS-DFO and PODS-ChxA”-DTPA allow for further radiolabeling with the positron emitter Zirconium-89 and the beta-emitter Lutetium-177, respectively.