Preclinical evaluation of [68Ga]Ga-AAZTA-FAPI-46: a novel PET tracer for targeting fibroblast activation protein (FAP)

Abstract Background The aim of this work was to demonstrate the suitability of AAZTA chelator conjugated to a FAPI-46-derived FAP inhibitor and labelled with gallium-68 as a potential PET tracer. Results Gallium-68 radiolabelling was achieved with high radiochemical yield at room temperature. The ne...

Full description

Saved in:
Bibliographic Details
Main Authors: Rebecca Rizzo, Paolo Rainone, Rachele Stefania, Sara Belloli, Silvia Valtorta, Angela Coliva, Marco Maspero, Lidia Avalle, Martina Capozza, Rosa Maria Moresco, Calogero D’Alessandria, Enzo Terreno
Format: Article
Language:English
Published: SpringerOpen 2025-08-01
Series:EJNMMI Radiopharmacy and Chemistry
Subjects:
Online Access:https://doi.org/10.1186/s41181-025-00375-2
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849234351368175616
author Rebecca Rizzo
Paolo Rainone
Rachele Stefania
Sara Belloli
Silvia Valtorta
Angela Coliva
Marco Maspero
Lidia Avalle
Martina Capozza
Rosa Maria Moresco
Calogero D’Alessandria
Enzo Terreno
author_facet Rebecca Rizzo
Paolo Rainone
Rachele Stefania
Sara Belloli
Silvia Valtorta
Angela Coliva
Marco Maspero
Lidia Avalle
Martina Capozza
Rosa Maria Moresco
Calogero D’Alessandria
Enzo Terreno
author_sort Rebecca Rizzo
collection DOAJ
description Abstract Background The aim of this work was to demonstrate the suitability of AAZTA chelator conjugated to a FAPI-46-derived FAP inhibitor and labelled with gallium-68 as a potential PET tracer. Results Gallium-68 radiolabelling was achieved with high radiochemical yield at room temperature. The new tracer was stable in different media, showing specific binding to FAP-protein both in vitro and in vivo, and a suitable biodistribution and clearance. High tumor uptake of the tracer (1.01 ± 0.12 SUV 35 min p.i.) was found in 4T1-tumor bearing mice, and blocking experiments demonstrated the high target specificity. Conclusion The substitution of the DOTA chelator with the AAZTA ligand on FAPI-46 moiety allowed a fast radiolabelling at room temperature of the PET tracer without influencing the biodistribution properties, such as clearance and FAP-mediated tumor uptake, but rather expanding the tracer applicability.
format Article
id doaj-art-9480bd55d0394618a8435f116d57ef63
institution Kabale University
issn 2365-421X
language English
publishDate 2025-08-01
publisher SpringerOpen
record_format Article
series EJNMMI Radiopharmacy and Chemistry
spelling doaj-art-9480bd55d0394618a8435f116d57ef632025-08-20T04:03:12ZengSpringerOpenEJNMMI Radiopharmacy and Chemistry2365-421X2025-08-0110111310.1186/s41181-025-00375-2Preclinical evaluation of [68Ga]Ga-AAZTA-FAPI-46: a novel PET tracer for targeting fibroblast activation protein (FAP)Rebecca Rizzo0Paolo Rainone1Rachele Stefania2Sara Belloli3Silvia Valtorta4Angela Coliva5Marco Maspero6Lidia Avalle7Martina Capozza8Rosa Maria Moresco9Calogero D’Alessandria10Enzo Terreno11Center for Biotechnology and Translational Medicine, University of TurinNuclear Medicine and PET Cyclotron Unit, IRCCS Ospedale San RaffaeleDISIT, University of Eastern PiedmontNuclear Medicine and PET Cyclotron Unit, IRCCS Ospedale San RaffaeleNuclear Medicine and PET Cyclotron Unit, IRCCS Ospedale San RaffaeleNuclear Medicine and PET Cyclotron Unit, IRCCS Ospedale San RaffaeleNuclear Medicine and PET Cyclotron Unit, IRCCS Ospedale San RaffaeleDISIT, University of Eastern PiedmontCenter for Biotechnology and Translational Medicine, University of TurinNuclear Medicine and PET Cyclotron Unit, IRCCS Ospedale San RaffaeleDepartment of Nuclear Medicine, TUM University Hospital rechts der IsarCenter for Biotechnology and Translational Medicine, University of TurinAbstract Background The aim of this work was to demonstrate the suitability of AAZTA chelator conjugated to a FAPI-46-derived FAP inhibitor and labelled with gallium-68 as a potential PET tracer. Results Gallium-68 radiolabelling was achieved with high radiochemical yield at room temperature. The new tracer was stable in different media, showing specific binding to FAP-protein both in vitro and in vivo, and a suitable biodistribution and clearance. High tumor uptake of the tracer (1.01 ± 0.12 SUV 35 min p.i.) was found in 4T1-tumor bearing mice, and blocking experiments demonstrated the high target specificity. Conclusion The substitution of the DOTA chelator with the AAZTA ligand on FAPI-46 moiety allowed a fast radiolabelling at room temperature of the PET tracer without influencing the biodistribution properties, such as clearance and FAP-mediated tumor uptake, but rather expanding the tracer applicability.https://doi.org/10.1186/s41181-025-00375-2AAZTAFAPPETFAPI-46GALLIUM-68
spellingShingle Rebecca Rizzo
Paolo Rainone
Rachele Stefania
Sara Belloli
Silvia Valtorta
Angela Coliva
Marco Maspero
Lidia Avalle
Martina Capozza
Rosa Maria Moresco
Calogero D’Alessandria
Enzo Terreno
Preclinical evaluation of [68Ga]Ga-AAZTA-FAPI-46: a novel PET tracer for targeting fibroblast activation protein (FAP)
EJNMMI Radiopharmacy and Chemistry
AAZTA
FAP
PET
FAPI-46
GALLIUM-68
title Preclinical evaluation of [68Ga]Ga-AAZTA-FAPI-46: a novel PET tracer for targeting fibroblast activation protein (FAP)
title_full Preclinical evaluation of [68Ga]Ga-AAZTA-FAPI-46: a novel PET tracer for targeting fibroblast activation protein (FAP)
title_fullStr Preclinical evaluation of [68Ga]Ga-AAZTA-FAPI-46: a novel PET tracer for targeting fibroblast activation protein (FAP)
title_full_unstemmed Preclinical evaluation of [68Ga]Ga-AAZTA-FAPI-46: a novel PET tracer for targeting fibroblast activation protein (FAP)
title_short Preclinical evaluation of [68Ga]Ga-AAZTA-FAPI-46: a novel PET tracer for targeting fibroblast activation protein (FAP)
title_sort preclinical evaluation of 68ga ga aazta fapi 46 a novel pet tracer for targeting fibroblast activation protein fap
topic AAZTA
FAP
PET
FAPI-46
GALLIUM-68
url https://doi.org/10.1186/s41181-025-00375-2
work_keys_str_mv AT rebeccarizzo preclinicalevaluationof68gagaaaztafapi46anovelpettracerfortargetingfibroblastactivationproteinfap
AT paolorainone preclinicalevaluationof68gagaaaztafapi46anovelpettracerfortargetingfibroblastactivationproteinfap
AT rachelestefania preclinicalevaluationof68gagaaaztafapi46anovelpettracerfortargetingfibroblastactivationproteinfap
AT sarabelloli preclinicalevaluationof68gagaaaztafapi46anovelpettracerfortargetingfibroblastactivationproteinfap
AT silviavaltorta preclinicalevaluationof68gagaaaztafapi46anovelpettracerfortargetingfibroblastactivationproteinfap
AT angelacoliva preclinicalevaluationof68gagaaaztafapi46anovelpettracerfortargetingfibroblastactivationproteinfap
AT marcomaspero preclinicalevaluationof68gagaaaztafapi46anovelpettracerfortargetingfibroblastactivationproteinfap
AT lidiaavalle preclinicalevaluationof68gagaaaztafapi46anovelpettracerfortargetingfibroblastactivationproteinfap
AT martinacapozza preclinicalevaluationof68gagaaaztafapi46anovelpettracerfortargetingfibroblastactivationproteinfap
AT rosamariamoresco preclinicalevaluationof68gagaaaztafapi46anovelpettracerfortargetingfibroblastactivationproteinfap
AT calogerodalessandria preclinicalevaluationof68gagaaaztafapi46anovelpettracerfortargetingfibroblastactivationproteinfap
AT enzoterreno preclinicalevaluationof68gagaaaztafapi46anovelpettracerfortargetingfibroblastactivationproteinfap