Uniform intratumoral distribution of radioactivity produced using two different radioagents, 64 Cu-cyclam-RAFT-c(-RGDfK-) 4 and 64 Cu-ATSM, improves therapeutic efficacy in a small animal tumor model

Background The present study proposed a new concept for targeted radionuclide therapy (TRT) to improve the intratumoral distribution of radioactivity using two different radiopharmaceuticals. We examined the efficacy of a combination of a tetrameric cyclic Arg-Gly-Asp (cRGD) peptide-based radiopharmaceutical, 64Cu-cyclam-RAFT-c(-RGDfK-)4 (64Cu-RaftRGD, an αVβ3 integrin [αVβ3] tracer), and 64Cu-diacetyl-bis (N4-methylthiosemicarbazone) (64Cu-ATSM, a supposed tracer for hypoxic metabolism) in a small animal tumor model.