By Charlotte Duchemin – Following the evaluation of the first two calls, PRISMAP has now entered a new phase with the first radionuclides being delivered. We have asked two of those projects to let us know about their experience so far.

Project 12 entitled “Added Value using Terbium-161 over Lutetium-177 in Combination with the metabolically more stable GRPR Ligand AMTG for Targeted Radiotherapy of GRPR-expressing Malignancies? – A Preclinical Evaluation” started on the 15 November 2022 with the first delivery of Tb-161 by PSI, followed by two additional deliveries in December 2022 by PSI and SCK CEN. Dr. rer. nat. Thomas Günther (TUM), project leader of project 12, said: “In a project, which involves the preclinical comparison of [161Tb]Tb-RM2 and its analog, [161Tb]Tb-AMTG, with their 177Lu-labeled derivatives, a higher gastrin-releasing peptide receptor (GRPR) affinity and metabolic stability in vivo was found for [161Tb]Tb-AMTG, which resulted in significantly improved activity levels in the PC-3 tumour xenograft at each time point examined (1, 4, 24 and 72 h p.i.). In combination with the higher rate of emitted Auger electrons per decay for Tb-161 as compared to Lu-177, the highest therapeutic efficacy is anticipated for [161Tb]Tb-AMTG, which will be further determined in future studies.”

Dr Alexis Broisat, project leader of project 11, has received a first batch of Tb-161 on 24 January 2023 from SCK CEN. This project aims at studying the “development and preclinical evaluation of a mesothelin-targeting theranostic agent”. Dr Broisat specifies that this first batch of Tb-161 allows his team to, on one side, test the capacity of non-conventional chelates developed at the University of Grenoble (France) to complex Tb and, on the other side, to develop the radiolabelling of nanobodies with this new and promising radionuclide for theranostic applications.

You can find more inspiration by browsing our accepted projects on the PRISMAP website!