Direct in vivo comparison of [18F]PSMA-1007 with [68Ga]Ga-PSMA-11 and [18F]AlF-PSMA-11 in mice bearing PSMA-expressing xenografts.

The aim of this preclinical study was to directly compare 18F]PSMA-1007 with both 68Ga]Ga-PSMA-11 and 18F]AlF-PSMA-11 in mice bearing PSMA-positive tumor xenografts. Uptake was assessed by PET/CT at 1, 2 and 4 h post-injection, and by ex vivo measurement after 4 h. 18F]PSMA-1007 demonstrated the highest tumor uptake of the three tracers. The high uptake in bone for mice injected with 18F]AlF-PSMA-11 suggested rapid in vivo decomposition. This was confirmed by an in vitro plasma stability study. • The uptake of 18F]PSMA-1007, 68Ga]Ga-PSMA-11 and 18F]AlF-PSMA-11 were compared. • 18F]PSMA-1007 demonstrated the highest tumor uptake of the three tracers. • 18F]AlF-PSMA-11 demonstrated low uptake in tumor and high uptake in bone. • The instability of 18F]AlF-PSMA-11 in plasma confirmed rapid in vivo degradation. [ABSTRACT FROM AUTHOR]