Evaluation of [<sup>64</sup>Cu]Cu-NOTA-PEG<sub>7</sub>-H-Tz for Pretargeted Imaging in LS174T Xenografts—Comparison to [<sup>111</sup>In]In-DOTA-PEG<sub>11</sub>-BisPy-Tz
Christian B. M. Poulie,
Jesper T. Jørgensen,
Vladimir Shalgunov,
Georgios Kougioumtzoglou,
Troels Elmer Jeppesen,
Andreas Kjaer,
Matthias M. Herth
Affiliations
Christian B. M. Poulie
Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark
Jesper T. Jørgensen
Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
Vladimir Shalgunov
Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark
Georgios Kougioumtzoglou
Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark
Troels Elmer Jeppesen
Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
Andreas Kjaer
Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
Matthias M. Herth
Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark
Pretargeted nuclear imaging for the diagnosis of various cancers is an emerging and fast developing field. The tetrazine ligation is currently considered the most promising reaction in this respect. Monoclonal antibodies are often the preferred choice as pretargeting vector due to their outstanding targeting properties. In this work, we evaluated the performance of [64Cu]Cu-NOTA-PEG7-H-Tz using a setup we previously used for [111In]In-DOTA-PEG11-BisPy-Tz, thereby allowing for comparison of the performance of these two promising pretargeting imaging agents. The evaluation included a comparison of the physicochemical properties of the compounds and their performance in an ex vivo blocking assay. Finally, [64Cu]Cu-NOTA-PEG7-H-Tz was evaluated in a pretargeted imaging study and compared to [111In]In-DOTA-PEG11-BisPy-Tz. Despite minor differences, this study indicated that both evaluated tetrazines are equally suited for pretargeted imaging.
