Enhanced contrast in FAP-targeting PET imaging with ⁶¹Cu-labeled FAP inhibitors: development and preclinical evaluation of novel [⁶¹Cu]Cu-Kalios PET radioligands.

ABSTRACT: Fibroblast activation protein (FAP)-targeting radioligands have gained attention for the ability to image multiple tumor types. Current FAP-targeting radioligands are labeled with 68Ga and 18F, but their short half-lives limit distribution range after production and later time-point imaging. This study describes the development Kalios, a novel class of NODAGA-conjugated FAP-targeting radioligands labeled with the cyclotron-produced Copper-61 (t1/2 = 3.33 h), for greater temporal range for FAP-targeted imaging. Four Kalios ligands were synthesized and radiolabeled with [61Cu]CuCl2 in high yield and radiochemical purity within 5 min at room temperature. All radioligands demonstrated high hydrophilicity and strong affinity for FAP, and were primarily internalized after incubation with FAP-pos

SUBMITTER: Millul J 

PROVIDER: S-EPMC12370594 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature