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Cao Z, Wichmann CW, Burvenich IJG, Osellame LD, Guo N, Rigopoulos A, O'Keefe GJ, Scott FE, Lorensuhewa N, Lynch KP, Scott AM. Radiolabelling and preclinical characterisation of [ 89Zr]Zr-Df-ATG-101 bispecific to PD-L1/4-1BB. Eur J Nucl Med Mol Imaging 2024; 51:3202-3214. [PMID: 38730087 PMCID: PMC11368977 DOI: 10.1007/s00259-024-06742-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 04/26/2024] [Indexed: 05/12/2024]
Abstract
PURPOSE ATG-101, a bispecific antibody that simultaneously targets the immune checkpoint PD-L1 and the costimulatory receptor 4-1BB, activates exhausted T cells upon PD-L1 crosslinking. Previous studies demonstrated promising anti-tumour efficacy of ATG-101 in preclinical models. Here, we labelled ATG-101 with 89Zr to confirm its tumour targeting effect and tissue biodistribution in a preclinical model. We also evaluated the use of immuno-PET to study tumour uptake of ATG-101 in vivo. METHODS ATG-101, anti-PD-L1, and an isotype control were conjugated with p-SCN-Deferoxamine (Df). The Df-conjugated antibodies were radiolabelled with 89Zr, and their radiochemical purity, immunoreactivity, and serum stability were assessed. We conducted PET/MRI and biodistribution studies on [89Zr]Zr-Df-ATG-101 in BALB/c nude mice bearing PD-L1-expressing MDA-MB-231 breast cancer xenografts for up to 10 days after intravenous administration of [89Zr]Zr-labelled antibodies. The specificity of [89Zr]Zr-Df-ATG-101 was evaluated through a competition study with unlabelled ATG-101 and anti-PD-L1 antibodies. RESULTS The Df-conjugation and [89Zr]Zr -radiolabelling did not affect the target binding of ATG-101. Biodistribution and imaging studies demonstrated biological similarity of [89Zr]Zr-Df-ATG-101 and [89Zr]Zr-Df-anti-PD-L1. Tumour uptake of [89Zr]Zr-Df-ATG-101 was clearly visualised using small-animal PET imaging up to 7 days post-injection. Competition studies confirmed the specificity of PD-L1 targeting in vivo. CONCLUSION [89Zr]Zr-Df-ATG-101 in vivo distribution is dependent on PD-L1 expression in the MDA-MB-231 xenograft model. Immuno-PET with [89Zr]Zr-Df-ATG-101 provides real-time information about ATG-101 distribution and tumour uptake in vivo. Our data support the use of [89Zr]Zr-Df-ATG-101 to assess tumour and tissue uptake of ATG-101.
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Affiliation(s)
- Zhipeng Cao
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, Melbourne, Australia
- School of Cancer Medicine, La Trobe University, Melbourne, Australia
- Department of Molecular Imaging and Therapy, Austin Health, Melbourne, Australia
| | - Christian Werner Wichmann
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, Melbourne, Australia
- School of Cancer Medicine, La Trobe University, Melbourne, Australia
- Department of Molecular Imaging and Therapy, Austin Health, Melbourne, Australia
- School of Chemistry - Bio21 Institute, University of Melbourne, Melbourne, Australia
| | - Ingrid Julienne Georgette Burvenich
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, Melbourne, Australia
- School of Cancer Medicine, La Trobe University, Melbourne, Australia
| | - Laura Danielle Osellame
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, Melbourne, Australia
- School of Cancer Medicine, La Trobe University, Melbourne, Australia
| | - Nancy Guo
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, Melbourne, Australia
| | - Angela Rigopoulos
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, Melbourne, Australia
| | - Graeme Joseph O'Keefe
- Department of Molecular Imaging and Therapy, Austin Health, Melbourne, Australia
- Department of Medicine, University of Melbourne, Melbourne, Australia
| | - Fiona Elizabeth Scott
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, Melbourne, Australia
- School of Cancer Medicine, La Trobe University, Melbourne, Australia
| | | | | | - Andrew Mark Scott
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, Melbourne, Australia.
- School of Cancer Medicine, La Trobe University, Melbourne, Australia.
- Department of Molecular Imaging and Therapy, Austin Health, Melbourne, Australia.
- Department of Medicine, University of Melbourne, Melbourne, Australia.
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MacManus MP, Akhurst T, Lewin SR, Hegi-Johnson F. Response to COVID-19 vaccination imaged by PD-L1 PET scanning. EJNMMI REPORTS 2024; 8:16. [PMID: 38844699 PMCID: PMC11156812 DOI: 10.1186/s41824-024-00196-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Accepted: 02/16/2024] [Indexed: 06/09/2024]
Abstract
BACKGROUND During a phase 0 clinical trial of an investigational programmed cell death ligand-1 (PD-L1) PET tracer in patients with non-small cell lung cancer (NSCLC), three patients received booster doses of COVID-19 vaccines before PD-L1 imaging. METHODS Five patients underwent whole-body PET/CT imaging with a novel PD-L1 tracer, constructed by attaching 89Zr to the anti PD-L1 antibody durvalumab. Intramuscular (deltoid) booster doses of mRNA BNT162b2 COVID-19 mRNA vaccine were coincidentally given to three patients in the month before PD-L1 tracer injection. RESULTS Two recently-vaccinated patients, in remission of NSCLC and receiving non-immunosuppressive cancer therapies (immunotherapy and tyrosine kinase inhibitor respectively), showed increasing PD-L1 tracer uptake in ipsilateral axillary lymph nodes. No asymmetric nodal uptake was seen in a third recently-vaccinated patient who was receiving immunosuppressive chemotherapy, or in two patients not recently-vaccinated. CONCLUSION Immune response to mRNA BNT162b2 vaccination may involve regulation by PD-L1 positive immune cells in local draining lymph nodes in immunocompetent patients. TRIAL REGISTRATION This trial was registered with the Australian New Zealand Clinical Trials Registry. Registration number ACTRN12621000171819. Date of Trial Registration 8/2/2021. Date of enrolment of 1st patient 11/4/2021. URL of trial registry record: https://www.australianclinicaltrials.gov.au/anzctr/trial/ACTRN12621000171819 .
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Affiliation(s)
- Michael P MacManus
- Department of Radiation Oncology, Peter MacCallum Cancer Centre, 305 Grattan Street, Melbourne, Vic, 3000, Australia.
- The Sir Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne, Australia.
| | - Tim Akhurst
- The Sir Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne, Australia
- Department of Molecular Imaging, Peter MacCallum Cancer Centre, Melbourne, Australia
| | - Sharon R Lewin
- Department of Infectious Diseases, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
- Victorian Infectious Diseases Service, Royal Melbourne Hospital at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
- Department of Infectious Diseases, Alfred Hospital and Monash University, Melbourne, Australia
| | - Fiona Hegi-Johnson
- Department of Radiation Oncology, Peter MacCallum Cancer Centre, 305 Grattan Street, Melbourne, Vic, 3000, Australia
- The Sir Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne, Australia
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Wuensche TE, Lyashchenko S, van Dongen GAMS, Vugts D. Good practices for 89Zr radiopharmaceutical production and quality control. EJNMMI Radiopharm Chem 2024; 9:40. [PMID: 38733556 PMCID: PMC11088613 DOI: 10.1186/s41181-024-00258-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 03/21/2024] [Indexed: 05/13/2024] Open
Abstract
BACKGROUND During the previous two decades, PET imaging of biopharmaceuticals radiolabeled with zirconium-89 has become a consistent tool in preclinical and clinical drug development and patient selection, primarily due to its advantageous physical properties that allow straightforward radiolabeling of antibodies (89Zr-immuno-PET). The extended half-life of 78.4 h permits flexibility with respect to the logistics of tracer production, transportation, and imaging and allows imaging at later points in time. Additionally, its relatively low positron energy contributes to high-sensitivity, high-resolution PET imaging. Considering the growing interest in radiolabeling antibodies, antibody derivatives, and other compound classes with 89Zr in both clinical and pre-clinical settings, there is an urgent need to acquire valuable recommendations and guidelines towards standardization of labeling procedures. MAIN BODY This review provides an overview of the key aspects of 89Zr-radiochemistry and radiopharmaceuticals. Production of 89Zr, conjugation with the mostly used chelators and radiolabeling strategies, and quality control of the radiolabeled products are described in detail, together with discussions about alternative options and critical steps, as well as recommendations for troubleshooting. Moreover, some historical background on 89Zr-immuno-PET, coordination chemistry of 89Zr, and future perspectives are provided. This review aims to serve as a quick-start guide for scientists new to the field of 89Zr-immuno-PET and to suggest approaches for harmonization and standardization of current procedures. CONCLUSION The favorable PET imaging characteristics of 89Zr, its excellent availability due to relatively simple production and purification processes, and the development of suitable bifunctional chelators have led to the widespread use of 89Zr. The combination of antibodies and 89Zr, known as 89Zr-immuno-PET, has become a cornerstone in drug development and patient selection in recent years. Despite the advanced state of 89Zr-immuno-PET, new developments in chelator conjugation and radiolabeling procedures, application in novel compound classes, and improved PET scanner technology and quantification methods continue to reshape its landscape towards improving clinical outcomes.
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Affiliation(s)
- Thomas Erik Wuensche
- Department of Radiology & Nuclear Medicine, Amsterdam UMC Location Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands.
| | - Serge Lyashchenko
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, USA
| | - Guus A M S van Dongen
- Department of Radiology & Nuclear Medicine, Amsterdam UMC Location Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands
- Amsterdam Neuroscience, Brain Imaging, Amsterdam, The Netherlands
| | - Danielle Vugts
- Department of Radiology & Nuclear Medicine, Amsterdam UMC Location Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands.
- Amsterdam Neuroscience, Brain Imaging, Amsterdam, The Netherlands.
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Noor A, Roselt PD, McGowan ER, Poniger S, Wheatcroft MP, Donnelly PS. Automated synthesis of [ 89Zr]ZrCl 4, [ 89Zr]ZrDFOSquaramide-bisPh(PSMA) and [ 89Zr]ZrDFOSquaramide-TATE. EJNMMI Radiopharm Chem 2024; 9:39. [PMID: 38717578 PMCID: PMC11078908 DOI: 10.1186/s41181-024-00270-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2024] [Accepted: 04/26/2024] [Indexed: 05/12/2024] Open
Abstract
BACKGROUND Automated [89Zr]Zr-radiolabeling processes have the potential to streamline the production of [89Zr]Zr-labelled PET imaging agents. Most radiolabeling protocols use [89Zr][Zr(ox)4]4- as the starting material and oxalate is removed after radiolabeling. In some instances, radiolabeling with [89Zr]ZrCl4 as starting material gives better radiochemical yields at lower reaction temperatures. In this work, a fully-automated process for production of [89Zr]ZrCl4 is reported and its use for the synthesis of [89Zr]ZrDFOSq-bisPhPSMA and [89Zr]ZrDFOSq-TATE. RESULTS A simple automated process for the isolation of [89Zr]ZrCl4 by trapping [89Zr][Zr(ox)4]4- on a bicarbonate-activated strong anion exchange cartridge followed by elution with 0.1 M HCl in 1 M NaCl was developed. [89Zr]ZrCl4 was routinely recovered from [89Zr][Zr(ox)4]4- in > 95% yield in mildly acidic solution of 0.1 M HCl in 1 M NaCl using a fully-automated process. The [89Zr]ZrCl4 was neutralized with sodium acetate buffer (0.25 M) removing the requirement for cumbersome manual neutralization with strong base. The mixture of [89Zr]ZrCl4 was used for direct automated radiolabeling reactions to produce [89Zr]Zr-DFOSquaramide-bisPhPSMA and [89Zr]ZrDFOSquaramide-TATE in 80-90% over all RCY in > 95% RCP. CONCLUSIONS This method for the production of [89Zr]ZrCl4 does not require removal of HCl by evaporation making this process relatively fast and efficient. The fully automated procedures for the production of [89Zr]ZrCl4 and its use in radiolabeling are well suited to support the centralized and standardized manufacture of multiple dose preparations of zirconium-89 based radiopharmaceuticals.
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Affiliation(s)
- Asif Noor
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia.
| | - Peter D Roselt
- Department of Radiopharmaceutical Sciences, Cancer Imaging, The Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Emily R McGowan
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Stan Poniger
- iPHASE Technologies Pty Ltd., Rowville, VIC, 3178, Australia
| | - Michael P Wheatcroft
- Telix Pharmaceuticals Limited, Suite 401, 55 Flemington Road, North Melbourne, VIC, 3051, Australia
| | - Paul S Donnelly
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia.
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Rudd SE, Noor A, Morgan KA, Donnelly PS. Diagnostic Positron Emission Tomography Imaging with Zirconium-89 Desferrioxamine B Squaramide: From Bench to Bedside. Acc Chem Res 2024; 57:1421-1433. [PMID: 38666539 DOI: 10.1021/acs.accounts.4c00092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Molecular imaging with antibodies radiolabeled with positron-emitting radionuclides combines the affinity and selectivity of antibodies with the sensitivity of Positron Emission Tomography (PET). PET imaging allows the visualization and quantification of the biodistribution of the injected radiolabeled antibody, which can be used to characterize specific biological interactions in individual patients. This characterization can provide information about the engagement of the antibody with a molecular target such as receptors present in elevated levels in tumors as well as providing insight into the distribution and clearance of the antibody. Potential applications of clinical PET with radiolabeled antibodies include identifying patients for targeted therapies, characterization of heterogeneous disease, and monitoring treatment response.Antibodies often take several days to clear from the blood pool and localize in tumors, so PET imaging with radiolabeled antibodies requires the use of a radionuclide with a similar radioactive half-life. Zirconium-89 is a positron-emitting radionuclide that has a radioactive half-life of 78 h and relatively low positron emission energy that is well suited to radiolabeling antibodies. It is essential that the zirconium-89 radionuclide be attached to the antibody through chemistry that provides an agent that is stable in vivo with respect to the dissociation of the radionuclide without compromising the biological activity of the antibody.This Account focuses on our research using a simple derivative of the bacterial siderophore desferrioxamine (DFO) with a squaramide ester functional group, DFO-squaramide (DFOSq), to link the chelator to antibodies. In our work, we produce conjugates with an average ∼4 chelators per antibody, and this does not compromise the binding of the antibody to the target. The resulting antibody conjugates of DFOSq are stable and can be easily radiolabeled with zirconium-89 in high radiochemical yields and purity. Automated methods for the radiolabeling of DFOSq-antibody conjugates have been developed to support multicenter clinical trials. Evaluation of several DFOSq conjugates with antibodies and low molecular weight targeting agents in tumor mouse models gave PET images with high tumor uptake and low background. The promising preclinical results supported the translation of this chemistry to human clinical trials using two different radiolabeled antibodies. The potential clinical impact of these ongoing clinical trials is discussed.The use of DFOSq to radiolabel relatively low molecular weight targeting molecules, peptides, and peptide mimetics is also presented. Low molecular weight molecules typically clear the blood pool and accumulate in target tissue more rapidly than antibodies, so they are usually radiolabeled with positron-emitting radionuclides with shorter radioactive half-lives such as fluorine-18 (t1/2 ∼ 110 min) or gallium-68 (t1/2 ∼ 68 min). Radiolabeling peptides and peptide mimetics with zirconium-89, with its longer radioactive half-life (t1/2 = 78 h), could facilitate the centralized manufacture and distribution of radiolabeled tracers. In addition, the ability to image patients at later time points with zirconium-89 based agents (e.g. 4-24 h after injection) may also allow the delineation of small or low-uptake disease sites as the delayed imaging results in increased clearance of the tracer from nontarget tissue and lower background signal.
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Affiliation(s)
- Stacey E Rudd
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Melbourne 3010, Australia
| | - Asif Noor
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Melbourne 3010, Australia
| | - Katherine A Morgan
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Melbourne 3010, Australia
| | - Paul S Donnelly
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Melbourne 3010, Australia
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Albanese V, Roccatello C, Pacifico S, Guerrini R, Preti D, Gentili S, Tegoni M, Remelli M, Bellotti D, Amico J, Gorgoni G, Cazzola E. Bifunctional octadentate pseudopeptides as Zirconium-89 chelators for immuno-PET applications. EJNMMI Radiopharm Chem 2024; 9:38. [PMID: 38705946 PMCID: PMC11070408 DOI: 10.1186/s41181-024-00263-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Accepted: 04/15/2024] [Indexed: 05/07/2024] Open
Abstract
BACKGROUND Positron emission tomography (PET) is a highly sensitive method that provides fine resolution images, useful in the field of clinical diagnostics. In this context, Zirconium-89 (89Zr)-based imaging agents have represented a great challenge in molecular imaging with immuno-PET, which employs antibodies (mAbs) as biological vectors. Indeed, immuno-PET requires radionuclides that can be attached to the mAb to provide stable in vivo conjugates, and for this purpose, the radioactive element should have a decay half-life compatible with the time needed for the biodistribution of the immunoglobulin. In this regard, 89Zr is an ideal radioisotope for immuno-PET because its half-life perfectly matches the in vivo pharmacokinetics of mAbs. RESULTS The main objective of this work was the design and synthesis of a series of bifunctional octadentate pseudopeptides able to generate stable 89Zr complexes. To achieve this, here we investigated hydroxamate, N-methylhydroxamate and catecholate chelating moieties in complexing radioactive zirconium. N-methylhydroxamate proved to be the most effective 89Zr-chelating group. Furthermore, the increased flexibility and hydrophilicity obtained by using polyoxyethylene groups spacing the hydroxamate units led to chelators capable of rapidly forming (15 min) stable and water-soluble complexes with 89Zr under mild reaction conditions (aqueous environment, room temperature, and physiological pH) that are mandatory for complexation reactions involving biomolecules. Additionally, we report challenge experiments with the competitor ligand EDTA and metal ions such as Fe3+, Zn2+ and Cu2+. In all examined conditions, the chelators demonstrated stability against transmetallation. Finally, a maleimide moiety was introduced to apply one of the most promising ligands in bioconjugation reactions through Thiol-Michael chemistry. CONCLUSION Combining solid phase and solution synthesis techniques, we identified novel 89Zr-chelating molecules with a peptide scaffold. The adopted chemical design allowed modulation of molecular flexibility, hydrophilicity, as well as the decoration with different zirconium chelating groups. Best results in terms of 89Zr-chelating properties were achieved with the N-methyl hydroxamate moiety. The Zirconium complexes obtained with the most effective compounds were water-soluble, stable to transmetallation, and resistant to peptidases for at least 6 days. Further studies are needed to assess the potential of this novel class of molecules as Zirconium-chelating agents for in vivo applications.
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Affiliation(s)
- Valentina Albanese
- Department of Environmental and Prevention Sciences, University of Ferrara, Palazzo Turchi di Bagno, C.So Ercole I d'Este 32, 44121, Ferrara, Italy.
| | - Chiara Roccatello
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, Via Luigi Borsari 46, 44121, Ferrara, Italy
| | - Salvatore Pacifico
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, Via Luigi Borsari 46, 44121, Ferrara, Italy
| | - Remo Guerrini
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, Via Luigi Borsari 46, 44121, Ferrara, Italy
| | - Delia Preti
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, Via Luigi Borsari 46, 44121, Ferrara, Italy
| | - Silvia Gentili
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area Delle Scienze 11/A, 43124, Parma, Italy
| | - Matteo Tegoni
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area Delle Scienze 11/A, 43124, Parma, Italy
| | - Maurizio Remelli
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, Via Luigi Borsari 46, 44121, Ferrara, Italy.
| | - Denise Bellotti
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, Via Luigi Borsari 46, 44121, Ferrara, Italy
| | - Jonathan Amico
- Department of Radiopharmaceutical, IRCCS Sacro Cuore Don Calabria Hospital, Via Don A. Sempreboni 5, 37024, Negrar di Valpolicella, Verona, Italy
| | - Giancarlo Gorgoni
- Department of Radiopharmaceutical, IRCCS Sacro Cuore Don Calabria Hospital, Via Don A. Sempreboni 5, 37024, Negrar di Valpolicella, Verona, Italy
| | - Emiliano Cazzola
- Department of Radiopharmaceutical, IRCCS Sacro Cuore Don Calabria Hospital, Via Don A. Sempreboni 5, 37024, Negrar di Valpolicella, Verona, Italy
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Ahn SH, Belanger AP. Automated radiolabeling and handling of 177 Lu- and 225 Ac-PSMA-617 using a robotic pipettor. J Labelled Comp Radiopharm 2024; 67:111-115. [PMID: 38296817 DOI: 10.1002/jlcr.4085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 12/21/2023] [Accepted: 01/16/2024] [Indexed: 02/02/2024]
Abstract
While automated modules for F-18 and C-11 radiosyntheses are standardized with features such as multiple reactors, vacuum connection and semi-preparative HPLC, labeling and processing of compounds with radiometals such as Zr-89, Lu-177 and Ac-225 often do not require complex manipulations and are frequently performed manually by a radiochemist. These procedures typically involve transferring solutions to and from vials using pipettes followed by heating of the reaction mixture, and do not require all the features found in most commercial automated synthesis units marketed as F-18 or C-11 modules. Here we present an efficient automated method for performing radiosyntheses involving radiometals by adapting a commercially available robotic pipettor originally developed for high-throughput processing of biological samples. While a robotic pipettor is less costly than a radiosynthesis module, it holds many similar advantages over manual radiosynthesis such as minimization of operator error, lower operator exposure rates, and abbreviated synthesis times, among others. To demonstrate the feasibility of using the OpenTrons OT-2 robotic pipettor to perform automated radiosyntheses, we radiolabeled and formulated 177 Lu-PSMA-617 and 225 Ac-PSMA-617 on the system. The OT-2 was then used to help streamline the quality control process for both products, further minimizing manual handling by and exposure to the radiochemist.
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Affiliation(s)
- Shin Hye Ahn
- Molecular Cancer Imaging Facility, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Anthony P Belanger
- Molecular Cancer Imaging Facility, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
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