SCN-PYTA

SCN-PYTA is a bifunctional chelator (BFC) based on an 18-membered macrocycle (PYTA) designed for the stable complexation of trivalent radiometals, such as Actinium-225 (225Ac), Lutetium-177 (177Lu), Indium-111 (111In), and Scandium-44 (44Sc). Developed by researchers at Oak Ridge National Laboratory (ORNL) and investigated by Convergent Therapeutics, it features an amine-reactive thiocyanate (SCN) group appended to the pyridine ring of the macrocycle, allowing for efficient conjugation to targeting vectors like monoclonal antibodies (e.g., rosopatamab and sacituzumab). SCN-PYTA enables rapid radiolabeling at room temperature with high yields and demonstrates exceptional in vitro stability, making it a versatile platform for developing theranostic radiopharmaceuticals for both diagnostic imaging and targeted alpha/beta particle therapy in various cancers, including PSMA-positive and TROP-2-positive malignancies.