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Wood JL, Ghosh S, Houston ZH, Fletcher NL, Humphries J, Mardon K, Akhter DT, Tieu W, Ivashkevich A, Wheatcroft MP, Thurecht KJ, Codd R. A first-in-class dual-chelator theranostic agent designed for use with imaging-therapy radiometal pairs of different elements. Chem Sci 2024; 15:11748-11760. [PMID: 39092114 PMCID: PMC11290327 DOI: 10.1039/d4sc02851a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Accepted: 05/21/2024] [Indexed: 08/04/2024] Open
Abstract
A covalent adduct of DFOB and DOTA separated by a l-lysine residue (DFOB-l-Lys-N 6-DOTA) exhibited remarkable regioselective metal binding, with {1H}-13C NMR spectral shifts supporting Zr(iv) coordinating to the DFOB unit, and Lu(iii) coordinating to the DOTA unit. This first-in-class, dual-chelator theranostic design could enable the use of imaging-therapy radiometal pairs of different elements, such as 89Zr for positron emission tomography (PET) imaging and 177Lu for low-energy β--particle radiation therapy. DFOB-l-Lys-N 6-DOTA was elaborated with an amine-terminated polyethylene glycol extender unit (PEG4) to give DFOB-N 2-(PEG4)-l-Lys-N 6-DOTA (compound D2) to enable installation of a phenyl-isothiocyanate group (Ph-NCS) for subsequent monoclonal antibody (mAb) conjugation (mAb = HuJ591). D2-mAb was radiolabeled with 89Zr or 177Lu to produce [89Zr]Zr-D2-mAb or [177Lu]Lu-D2-mAb, respectively, and in vivo PET/CT imaging and in vivo/ex vivo biodistribution properties measured with the matched controls [89Zr]Zr-DFOB-mAb or [177Lu]Lu-DOTA-mAb in a murine LNCaP prostate tumour xenograft model. The 89Zr-immuno-PET imaging function of [89Zr]Zr-D2-mAb and [89Zr]Zr-DFOB-mAb showed no significant difference in tumour accumulation at 48 or 120 h post injection. [89Zr]Zr-D2-mAb and [177Lu]Lu-D2-mAb showed similar ex vivo biodistribution properties at 120 h post-injection. Tumour uptake of [177Lu]Lu-D2-mAb shown by SPECT/CT imaging at 48 h and 120 h post-injection supported the therapeutic function of D2, which was corroborated by similar therapeutic efficacy between [177Lu]Lu-D2-mAb and [177Lu]Lu-DOTA-mAb, both showing a sustained reduction in tumour volume (>80% over 65 d) compared to vehicle. The work identifies D2 as a trifunctional chelator that could expand capabilities in mixed-element radiometal theranostics to improve dosimetry and the clinical outcomes of molecularly targeted radiation.
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Affiliation(s)
- James L Wood
- The University of Sydney, School of Medical Sciences New South Wales 2006 Australia
- Centre for Advanced Imaging (CAI), Australian Institute for Bioengineering and Nanotechnology (AIBN) and ARC Training Centre for Innovation in Biomedical Imaging Technology, The University of Queensland Brisbane Queensland 4072 Australia
| | - Saikat Ghosh
- Centre for Advanced Imaging (CAI), Australian Institute for Bioengineering and Nanotechnology (AIBN) and ARC Training Centre for Innovation in Biomedical Imaging Technology, The University of Queensland Brisbane Queensland 4072 Australia
| | - Zachary H Houston
- Centre for Advanced Imaging (CAI), Australian Institute for Bioengineering and Nanotechnology (AIBN) and ARC Training Centre for Innovation in Biomedical Imaging Technology, The University of Queensland Brisbane Queensland 4072 Australia
| | - Nicholas L Fletcher
- Centre for Advanced Imaging (CAI), Australian Institute for Bioengineering and Nanotechnology (AIBN) and ARC Training Centre for Innovation in Biomedical Imaging Technology, The University of Queensland Brisbane Queensland 4072 Australia
| | - James Humphries
- Centre for Advanced Imaging (CAI), Australian Institute for Bioengineering and Nanotechnology (AIBN) and ARC Training Centre for Innovation in Biomedical Imaging Technology, The University of Queensland Brisbane Queensland 4072 Australia
| | - Karine Mardon
- Centre for Advanced Imaging (CAI), Australian Institute for Bioengineering and Nanotechnology (AIBN) and ARC Training Centre for Innovation in Biomedical Imaging Technology, The University of Queensland Brisbane Queensland 4072 Australia
| | - Dewan T Akhter
- Centre for Advanced Imaging (CAI), Australian Institute for Bioengineering and Nanotechnology (AIBN) and ARC Training Centre for Innovation in Biomedical Imaging Technology, The University of Queensland Brisbane Queensland 4072 Australia
| | - William Tieu
- Molecular Imaging and Therapy Research Unit (MITRU), South Australian Health and Medical Research Institute (SAHMRI) Adelaide Australia
| | | | | | - Kristofer J Thurecht
- Centre for Advanced Imaging (CAI), Australian Institute for Bioengineering and Nanotechnology (AIBN) and ARC Training Centre for Innovation in Biomedical Imaging Technology, The University of Queensland Brisbane Queensland 4072 Australia
| | - Rachel Codd
- The University of Sydney, School of Medical Sciences New South Wales 2006 Australia
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Salih AK, Khozeimeh Sarbisheh E, Raheem SJ, Dominguez-Garcia M, Mehlhorn HH, Price EW. Synthesis and evaluation of bifunctional DFO2K: a modular chelator with ideal properties for zirconium-89 chelation. Dalton Trans 2024. [PMID: 39041240 DOI: 10.1039/d4dt01830c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/24/2024]
Abstract
The synthesis and evaluation of the newest generation of our DFO2 chelator family-DFO2K-is described. DFO2K was designed with a simple synthetic route to access different bifunctional derivatives, with each derivative having similar metal ion coordination spheres and high denticity (up to 12 coordinate) to ensure stable coordination of zirconium-89. The high denticity could potentially enhance stability with other large oxophilic radiometals. Zirconium-89 is the most popular radionuclide to pair with large macromolecules such as antibodies (immunoPET) for positron emission tomography applications. Although clinically successful, the stability of the "gold standard" chelator desferrioxamine B (DFO) can be improved as significant bone uptake is observed in animal models, despite no obvious stability issues in humans. Following the synthesis of DFO2K we assessed its radiolabeling efficiency with zirconium-89 and compared with DFO, which revealed rapid and nearly identical radiolabeling kinetics to DFO. The resultant [89Zr]Zr-DFO2K complex showed improved stability over [89Zr]Zr-DFO in different in vitro stability assays such as hydroxyapatite and 1000-fold molar excess EDTA challenges. Furthermore, biodistribution studies of the non-bifunctional chelators in healthy mice showed that [89Zr]Zr-DFO2K had a similar distribution profile and clearance to [89Zr]Zr-DFO. The bifunctional derivative p-SCN-Ph-DFO2K was conjugated to a non-specific human IgG antibody and evaluated after 2 weeks circulating in healthy female CD1 mice. Mice administered [89Zr]Zr-DFO2K-IgG showed substantially lower bone uptake in PET-CT images than [89Zr]Zr-DFO-IgG, with PET ROI data and ex vivo biodistribution revealing a statistically significantly lower bone uptake for DFO2K. Overall, owing to its high denticity, ease of synthesis, improved solubility over DFO2 and DFO2p, and stable chelation of zirconium-89, DFO2K appears to be an improved alternative chelator to DFO for zirconium-89 chelation.
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Affiliation(s)
- Akam K Salih
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, Saskatoon, SK, 110 Science Place, S7N-5C9, Canada.
| | | | - Shvan J Raheem
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, Saskatoon, SK, 110 Science Place, S7N-5C9, Canada.
| | - Moralba Dominguez-Garcia
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, Saskatoon, SK, 110 Science Place, S7N-5C9, Canada.
| | - Hillary H Mehlhorn
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, Saskatoon, SK, 110 Science Place, S7N-5C9, Canada.
| | - Eric W Price
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, Saskatoon, SK, 110 Science Place, S7N-5C9, Canada.
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Mangin F, Fonquernie O, Jewula P, Brandès S, Penouilh MJ, Bonnin Q, Vincent B, Espinosa E, Aubert E, Meyer M, Chambron JC. Combining Desferriferrioxamine B and 1-Hydroxy-2-Piperidone ((PIPO)H) to Chelate Zirconium. Solution Structure of a Model Complex of the [ 89Zr]Zr-DFOcyclo*-mAb Radioimmunoconjugate. Chempluschem 2024; 89:e202400062. [PMID: 38613508 DOI: 10.1002/cplu.202400062] [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: 01/23/2024] [Revised: 03/18/2024] [Indexed: 04/15/2024]
Abstract
89Zr-immunoPET is a hot topic as 89Zr cumulates the advantages of 64Cu and 124I without their drawbacks. We report the synthesis of a model ligand of a chiral bioconjugable tetrahydroxamic chelator combining the desferriferrioxamine B siderophore and 1-hydroxy-2-piperidone ((PIPO)H), a chiral cyclic hydroxamic acid derivative, and the study by NMR spectroscopy of its zirconium complex. Nuclear Overhauser effect measurements (ROESY) indicated that the complex exists in the form of two diastereomers, in 77 : 23 ratio, resulting from the combination of the central chiralities at the 3-C of the (PIPO)H component and at the Zr4+ cation. The 44 lowest energy structures out of more than 1000 configurations/conformations returned by calculations based on density functional theory were examined. Comparison of the ROESY data and the calculated interatomic H⋅⋅⋅H distances allowed us to select the most probable configuration and conformations of the major complex.
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Affiliation(s)
- Floriane Mangin
- Institut de Chimie Moléculaire de l'Université de Bourgogne UMR 6302 CNRS, Université de Bourgogne, 9, avenue Alain Savary, BP 47870, 21078, Dijon Cedex, France
| | - Osian Fonquernie
- Institut de Chimie Moléculaire de l'Université de Bourgogne UMR 6302 CNRS, Université de Bourgogne, 9, avenue Alain Savary, BP 47870, 21078, Dijon Cedex, France
| | - Pawel Jewula
- Institut de Chimie Moléculaire de l'Université de Bourgogne UMR 6302 CNRS, Université de Bourgogne, 9, avenue Alain Savary, BP 47870, 21078, Dijon Cedex, France
| | - Stéphane Brandès
- Institut de Chimie Moléculaire de l'Université de Bourgogne UMR 6302 CNRS, Université de Bourgogne, 9, avenue Alain Savary, BP 47870, 21078, Dijon Cedex, France
| | - Marie-José Penouilh
- Institut de Chimie Moléculaire de l'Université de Bourgogne UMR 6302 CNRS, Université de Bourgogne, 9, avenue Alain Savary, BP 47870, 21078, Dijon Cedex, France
| | - Quentin Bonnin
- Institut de Chimie Moléculaire de l'Université de Bourgogne UMR 6302 CNRS, Université de Bourgogne, 9, avenue Alain Savary, BP 47870, 21078, Dijon Cedex, France
| | - Bruno Vincent
- Institut de Chimie de Strasbourg UMR 7177 CNRS, Université de Strasbourg, 4, rue Blaise Pascal, 67070, Strasbourg, France
| | | | | | - Michel Meyer
- Institut de Chimie Moléculaire de l'Université de Bourgogne UMR 6302 CNRS, Université de Bourgogne, 9, avenue Alain Savary, BP 47870, 21078, Dijon Cedex, France
| | - Jean-Claude Chambron
- Institut de Chimie Moléculaire de l'Université de Bourgogne UMR 6302 CNRS, Université de Bourgogne, 9, avenue Alain Savary, BP 47870, 21078, Dijon Cedex, France
- Institut de Chimie de Strasbourg UMR 7177 CNRS, Université de Strasbourg, 4, rue Blaise Pascal, 67070, Strasbourg, France
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Badier L, Quelven I. Zirconium 89 and Copper 64 for ImmunoPET: From Antibody Bioconjugation and Radiolabeling to Molecular Imaging. Pharmaceutics 2024; 16:882. [PMID: 39065579 PMCID: PMC11279968 DOI: 10.3390/pharmaceutics16070882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 06/15/2024] [Accepted: 06/24/2024] [Indexed: 07/28/2024] Open
Abstract
Immunotherapy has transformed cancer treatment. Nevertheless, given the heterogeneity of clinical efficacy, the multiplicity of treatment options available and the possibility of serious adverse effects, selecting the most effective treatment has become the greatest challenge. Molecular imaging offers an attractive way for this purpose. ImmunoPET provides specific imaging with positron emission tomography (PET) using monoclonal antibodies (mAb) or its fragments as vector. By combining the high targeting specificity of mAb and the sensitivity of PET technique, immunoPET could noninvasively and dynamically reveal tumor antigens expression and provide theranostic tools of several types of malignancies. Because of their slow kinetics, mAbs require radioelements defined by a consistent half-life. Zirconium 89 (89Zr) and Copper 64 (64Cu) are radiometals with half-lives suitable for mAb labeling. Radiolabeling with a radiometal requires the prior use of a bifunctional chelate agent (BFCA) to functionalize mAb for radiometal chelation, in a second step. There are a number of BFCA available and much research is focused on antibody functionalization techniques or on developing the optimum chelating agent depending the selected radiometal. In this manuscript, we present a critical account of radiochemical techniques with radionuclides 89Zr and 64Cu and their applications in preclinical and clinical immuno-PET imaging.
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Affiliation(s)
| | - Isabelle Quelven
- Toulouse NeuroImaging Center (ToNIC), INSERM/UPS UMR 1214, University Hospital of Toulouse-Purpan, CEDEX 3, 31024 Toulouse, France;
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Vizier R, Adumeau P, Moreau M, Goncalves V, Denat F. Moving Beyond Isothiocyanates: A Look at the Stability of Conjugation Links Toward Radiolysis in 89Zr-Labeled Immunoconjugates. Bioconjug Chem 2024; 35:633-637. [PMID: 38656148 DOI: 10.1021/acs.bioconjchem.4c00105] [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: 04/26/2024]
Abstract
Zirconium-89 is the most widely used radioisotope for immunoPET because its physical half-life (78.2 h) suits the one of antibodies. Desferrioxamine B (DFO) is the standard chelator for the complexation of zirconium(IV), and its bifunctional version, containing a phenylisothiocyanate function, is the most commonly used for the conjugation of DFO to proteins. However, preliminary results have shown that the thiourea link obtained from the conjugation of isothiocyanate and lysines is sensitive to the ionizing radiation generated by the radioisotope, leading to the rupture of the link and the release of the chelator/radiometal complex. This radiolysis phenomenon could produce nonspecific signal and prevent the detection of bone metastasis, as free zirconium accumulates into the bones. The aim of this work was to study the stability of a selection of conjugation linkers in 89Zr-labeled immunoconjugates. We have synthesized several DFO-based bifunctional chelators appended with an isothiocyanate moiety, a bicyclononyne, or a squaramate ester. Two antibodies (trastuzumab and rituximab) were conjugated and radiolabeled with zirconium-89. The effect of increasing activities of zirconium-89 on the integrity of the bioconjugate bearing thiourea links was evaluated as well as the impact of the presence of a radioprotectant. The stability of the radiolabeled antibodies was studied over 7 days in PBS and human plasma. Radioconjugates' integrity was evaluated using iTLC and size-exclusion chromatography. This study shows that the nature of the linker between the chelator and biomolecule can have a strong impact on the stability of the 89Zr-labeled conjugates, as well as on the aggregation of the conjugates.
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Affiliation(s)
- Romane Vizier
- Institut de Chimie Moléculaire de l'Université de Bourgogne, UMR 6302, CNRS, Université de Bourgogne, Dijon 21000, France
| | - Pierre Adumeau
- Institut de Chimie Moléculaire de l'Université de Bourgogne, UMR 6302, CNRS, Université de Bourgogne, Dijon 21000, France
| | - Mathieu Moreau
- Institut de Chimie Moléculaire de l'Université de Bourgogne, UMR 6302, CNRS, Université de Bourgogne, Dijon 21000, France
| | - Victor Goncalves
- Institut de Chimie Moléculaire de l'Université de Bourgogne, UMR 6302, CNRS, Université de Bourgogne, Dijon 21000, France
| | - Franck Denat
- Institut de Chimie Moléculaire de l'Université de Bourgogne, UMR 6302, CNRS, Université de Bourgogne, Dijon 21000, France
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6
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Sallam M, Nguyen NT, Sainsbury F, Kimizuka N, Muyldermans S, Benešová-Schäfer M. PSMA-targeted radiotheranostics in modern nuclear medicine: then, now, and what of the future? Theranostics 2024; 14:3043-3079. [PMID: 38855174 PMCID: PMC11155394 DOI: 10.7150/thno.92612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Accepted: 04/04/2024] [Indexed: 06/11/2024] Open
Abstract
In 1853, the perception of prostate cancer (PCa) as a rare ailment prevailed, was described by the eminent Londoner surgeon John Adams. Rapidly forward to 2018, the landscape dramatically altered. Currently, men face a one-in-nine lifetime risk of PCa, accentuated by improved diagnostic methods and an ageing population. With more than three million men in the United States alone grappling with this disease, the overall risk of succumbing to stands at one in 39. The intricate clinical and biological diversity of PCa poses serious challenges in terms of imaging, ongoing monitoring, and disease management. In the field of theranostics, diagnostic and therapeutic approaches that harmoniously merge targeted imaging with treatments are integrated. A pivotal player in this arena is radiotheranostics, employing radionuclides for both imaging and therapy, with prostate-specific membrane antigen (PSMA) at the forefront. Clinical milestones have been reached, including FDA- and/or EMA-approved PSMA-targeted radiodiagnostic agents, such as [18F]DCFPyL (PYLARIFY®, Lantheus Holdings), [18F]rhPSMA-7.3 (POSLUMA®, Blue Earth Diagnostics) and [68Ga]Ga-PSMA-11 (Locametz®, Novartis/ ILLUCCIX®, Telix Pharmaceuticals), as well as PSMA-targeted radiotherapeutic agents, such as [177Lu]Lu-PSMA-617 (Pluvicto®, Novartis). Concurrently, ligand-drug and immune therapies designed to target PSMA are being advanced through rigorous preclinical research and clinical trials. This review delves into the annals of PSMA-targeted radiotheranostics, exploring its historical evolution as a signature molecule in PCa management. We scrutinise its clinical ramifications, acknowledge its limitations, and peer into the avenues that need further exploration. In the crucible of scientific inquiry, we aim to illuminate the path toward a future where the enigma of PCa is deciphered and where its menace is met with precise and effective countermeasures. In the following sections, we discuss the intriguing terrain of PCa radiotheranostics through the lens of PSMA, with the fervent hope of advancing our understanding and enhancing clinical practice.
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Affiliation(s)
- Mohamed Sallam
- Queensland Micro- and Nanotechnology Centre (QMNC), Griffith University, Nathan Campus, Nathan, QLD 4111, Australia
- School of Environment and Science (ESC), Griffith University, Nathan Campus, Nathan, QLD 4111, Australia
- Griffith Institute for Drug Discovery (GRIDD), Griffith University, Nathan Campus, Nathan, QLD 4111, Australia
| | - Nam-Trung Nguyen
- Queensland Micro- and Nanotechnology Centre (QMNC), Griffith University, Nathan Campus, Nathan, QLD 4111, Australia
| | - Frank Sainsbury
- School of Environment and Science (ESC), Griffith University, Nathan Campus, Nathan, QLD 4111, Australia
- Griffith Institute for Drug Discovery (GRIDD), Griffith University, Nathan Campus, Nathan, QLD 4111, Australia
| | - Nobuo Kimizuka
- Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
- Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
- Research Center for Negative Emissions Technologies (K-NETs), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Serge Muyldermans
- Laboratory of Cellular and Molecular Immunology (CMIM), Vrije Universiteit Brussel, 1050 Brussels, Belgium
| | - Martina Benešová-Schäfer
- Research Group Molecular Biology of Systemic Radiotherapy, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
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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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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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Chen Z, Yang Q, Song L, Qiu Y, Wang T, Wu S, Huang W, Sun X, Wang A, Kang L. Enhanced Theranostic Efficacy of 89Zr and 177Lu-Labeled Aflibercept in Renal Cancer: A Viable Option for Clinical Practice. Mol Pharm 2024; 21:2544-2554. [PMID: 38588328 DOI: 10.1021/acs.molpharmaceut.4c00084] [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] [Indexed: 04/10/2024]
Abstract
Vascular endothelial growth factor (VEGF) targeted therapy serves as an important therapeutic approach for renal cancer, but its clinical effectiveness is unsatisfactory. Moreover, there is a lack of reliable biomarkers for preoperative assessment of tumor VEGF expression. This study aimed to explore the potential for further applications of 177Lu/89Zr-labeled aflibercept (Abe), a VEGF-binding agent, in imaging visualization of VEGF expression and therapy for renal cancer. To determine specificity uptake in renal cancer, BALB/c mice with VEGF-expressing Renca tumor were intravenously injected with [89Zr]Zr-Abe, [177Lu]Lu-Abe, or Cy5.5-Abe and the blocking group was designed as a control group. PET, SPECT, and fluorescence images were acquired, and the biodistribution of [89Zr]Zr-Abe and [177Lu]Lu-Abe was performed. Additionally, the [177Lu]Lu-Abe, [177Lu]Lu-Abe-block, 177Lu only, Abe only, and PBS groups were compared for evaluation of the therapeutic effect. To assess the safety, we monitored and evaluated the body weight, blood biochemistry analysis, and whole blood analysis and major organs were stained with hematoxylin and eosin after [177Lu]Lu-Abe treatment. DOTA-Abe was successfully labeled with 177Lu and Df-Abe with 89Zr in our study. The uptake in tumor of [89Zr]Zr-Abe was significantly higher than that of [89Zr]Zr-Abe-block (P < 0.05) and provided excellent tumor contrast in PET images. [177Lu]Lu-Abe demonstrated promising tumor-specific targeting capability with a high and persistent tumor uptake. The standardized tumor volume of [177Lu]Lu-Abe was significantly smaller than those of other treatment groups (P < 0.05). [177Lu]Lu-Abe also had smaller tumor volumes and reduced expression of VEGF and CD31 compared to those of the control groups. Fluorescence images demonstrate higher tumor uptake in the Cy5.5-Abe group compared to the Cy5.5-Abe-block group (P < 0.05). In conclusion, [89Zr]Zr-Abe enables noninvasive analysis of VEGF expression, serving as a valuable tool for assessing the VEGF-targeted therapy effect. Additionally, all of the findings support the enhanced therapeutic efficacy and safety of [177Lu]Lu-Abe, making it a viable option for clinical practice in renal cancer.
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Affiliation(s)
- Zhao Chen
- Department of Nuclear Medicine, Peking University First Hospital, Beijing 100034, China
| | - Qi Yang
- Department of Nuclear Medicine, Peking University First Hospital, Beijing 100034, China
| | - Lele Song
- Department of Nuclear Medicine, Peking University First Hospital, Beijing 100034, China
| | - Yongkang Qiu
- Department of Nuclear Medicine, Peking University First Hospital, Beijing 100034, China
| | - Tianyao Wang
- Department of Nuclear Medicine, Peking University First Hospital, Beijing 100034, China
| | - Sitong Wu
- Department of Interventional Radiology and Vascular Surgery, Peking University First Hospital, Beijing 100034, China
| | - Wenpeng Huang
- Department of Nuclear Medicine, Peking University First Hospital, Beijing 100034, China
| | - Xinyao Sun
- Department of Nuclear Medicine, Peking University First Hospital, Beijing 100034, China
| | - Aixiang Wang
- Department of Urology, Peking University First Hospital, Beijing 100034, China
- Institute of Urology, Peking University, Beijing 100034, China
| | - Lei Kang
- Department of Nuclear Medicine, Peking University First Hospital, Beijing 100034, China
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10
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Basuli F, Vasalatiy O, Shi J, Lane KC, Escorcia FE, Swenson RE. Preparation of a Zirconium-89 Labeled Clickable DOTA Complex and Its Antibody Conjugate. Pharmaceuticals (Basel) 2024; 17:480. [PMID: 38675440 PMCID: PMC11053460 DOI: 10.3390/ph17040480] [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: 03/01/2024] [Revised: 03/31/2024] [Accepted: 04/03/2024] [Indexed: 04/28/2024] Open
Abstract
Desferrioxamine B (DFO) is the clinical standard chelator for preparing zirconium-89 labeled antibodies. In the current study, the stabilities of a zirconium-89 labeled panitumumab (PAN; Vectibix®) with three different chelators (DFO, DFO*, and DOTA) were compared. PAN is an anti-HER1/EGFR monoclonal antibody approved by the FDA for the treatment of HER1-expressing colorectal cancers and was used as the model antibody for this study. DFO/DFO* conjugates of PAN were directly radiolabeled with zirconium-89 at room temperature to produce [89Zr]Zr-DFO/DFO*-PAN conjugates following a well-established procedure. A zirconium-89 labeled DOTA-PAN conjugate was prepared by an indirect radiolabeling method. A cyclooctyne-linked DOTA chelator (BCN-DOTA-GA) was first radiolabeled with zirconium-89 at 90 °C under a two-step basic pH adjustment method followed by conjugation with PAN-tetrazene at 37 °C to produce a labeled conjugate, BCN-[89Zr]Zr-DOTA-GA-PAN. High reproducibility of the radiolabeling was observed via this two-step basic pH adjustment. The overall radiochemical yield was 40-50% (n = 12, decay uncorrected) with a radiochemical purity of >95% in 2 h synthesis time. All three conjugates were stable in whole human serum for up to 7 days at 37 °C. The kinetic inertness of the conjugates was assessed against the EDTA challenge. BCN-[89Zr]Zr-DOTA-GA-PAN exhibited excellent inertness followed by [89Zr]Zr-DFO*-PAN. [89Zr]Zr-DFO-PAN displayed the lowest level of inertness.
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Affiliation(s)
- Falguni Basuli
- Chemistry and Synthesis Center, National Heart, Lung and Blood Institute, Bethesda, MD 20892, USA; (O.V.); (J.S.); (K.C.L.); (R.E.S.)
| | - Olga Vasalatiy
- Chemistry and Synthesis Center, National Heart, Lung and Blood Institute, Bethesda, MD 20892, USA; (O.V.); (J.S.); (K.C.L.); (R.E.S.)
| | - Jianfeng Shi
- Chemistry and Synthesis Center, National Heart, Lung and Blood Institute, Bethesda, MD 20892, USA; (O.V.); (J.S.); (K.C.L.); (R.E.S.)
| | - Kelly C. Lane
- Chemistry and Synthesis Center, National Heart, Lung and Blood Institute, Bethesda, MD 20892, USA; (O.V.); (J.S.); (K.C.L.); (R.E.S.)
| | - Freddy E. Escorcia
- Molecular Imaging Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA;
- Radiation Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Rolf E. Swenson
- Chemistry and Synthesis Center, National Heart, Lung and Blood Institute, Bethesda, MD 20892, USA; (O.V.); (J.S.); (K.C.L.); (R.E.S.)
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11
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Lin D, Lechermann LM, Huestis MP, Marik J, Sap JBI. Light-Driven Radiochemistry with Fluorine-18, Carbon-11 and Zirconium-89. Angew Chem Int Ed Engl 2024; 63:e202317136. [PMID: 38135665 DOI: 10.1002/anie.202317136] [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: 11/11/2023] [Revised: 12/18/2023] [Accepted: 12/20/2023] [Indexed: 12/24/2023]
Abstract
This review discusses recent advances in light-driven radiochemistry for three key isotopes: fluorine-18, carbon-11, and zirconium-89, and their applications in positron emission tomography (PET). In the case of fluorine-18, the predominant approach involves the use of cyclotron-produced [18F]fluoride or reagents derived thereof. Light serves to activate either the substrate or the fluorine-18 labeled reagent. Advancements in carbon-11 photo-mediated radiochemistry have been leveraged for the radiolabeling of small molecules, achieving various transformations, including 11C-methylation, 11C-carboxylation, 11C-carbonylation, and 11C-cyanation. Contrastingly, zirconium-89 photo-mediated radiochemistry differs from fluorine-18 and carbon-11 approaches. In these cases, light facilitates a postlabeling click reaction, which has proven valuable for the labeling of large biomolecules such as monoclonal antibodies (mAbs). New technological developments, such as the incorporation of photoreactors in commercial radiosynthesizers, illustrate the commitment the field is making in embracing photochemistry. Taken together, these advances in photo-mediated radiochemistry enable radiochemists to apply new retrosynthetic strategies in accessing novel PET radiotracers.
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Affiliation(s)
- Daniel Lin
- Department of Translational Imaging, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
- Current address: University of Southern California Department of Chemistry, Loker Hydrocarbon Research Institute, 837 Bloom Walk, Los Angeles, CA 90089, USA
| | - Laura M Lechermann
- Department of Translational Imaging, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Malcolm P Huestis
- Discovery Chemistry, Genentech, Inc., DNA Way, South San Francisco, CA 94080, USA
| | - Jan Marik
- Department of Translational Imaging, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
- Discovery Chemistry, Genentech, Inc., DNA Way, South San Francisco, CA 94080, USA
| | - Jeroen B I Sap
- Department of Translational Imaging, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
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12
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Kim GG, Lee H, Jeong DB, Kim SW, So JS. Long-Term Tumor-Targeting Effect of E. coli as a Drug Delivery System. Pharmaceuticals (Basel) 2024; 17:421. [PMID: 38675383 PMCID: PMC11053500 DOI: 10.3390/ph17040421] [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: 02/27/2024] [Revised: 03/21/2024] [Accepted: 03/22/2024] [Indexed: 04/28/2024] Open
Abstract
To overcome the limitations of current nano/micro-scale drug delivery systems, an Escherichia coli (E. coli)-based drug delivery system could be a potential alternative, and an effective tumor-targeting delivery system can be developed by attempting to perform chemical binding to the primary amine group of a cell membrane protein. In addition, positron emission tomography (PET) is a representative non-invasive imaging technology and is actively used in the field of drug delivery along with radioisotopes capable of long-term tracking, such as zirconium-89 (89Zr). The membrane proteins were labeled with 89Zr using chelate (DFO), and not only was the long-term biodistribution in tumors and major organs evaluated in the body, but the labeling stability of 89Zr conjugated to the membrane proteins was also evaluated through continuous tracking. E. coli accumulated at high levels in the tumor within 5 min (initial time) after tail intravenous injection, and when observed after 6 days, 89Zr-DFO on the surface of E. coli was found to be stable for a long period of time in the body. In this study, we demonstrated the long-term biodistribution and tumor-targeting effect of an E. coli-based drug delivery system and verified the in vivo stability of radioisotopes labeled on the surface of E. coli.
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Affiliation(s)
- Gun Gyun Kim
- Department of Nuclear Medicine, Dongnam Institute of Radiological and Medical Sciences, Busan 46033, Republic of Korea; (G.G.K.); (H.L.); (D.B.J.)
| | - Hongje Lee
- Department of Nuclear Medicine, Dongnam Institute of Radiological and Medical Sciences, Busan 46033, Republic of Korea; (G.G.K.); (H.L.); (D.B.J.)
| | - Dan Bi Jeong
- Department of Nuclear Medicine, Dongnam Institute of Radiological and Medical Sciences, Busan 46033, Republic of Korea; (G.G.K.); (H.L.); (D.B.J.)
- Department of Advanced Materials Chemistry, Dongguk University, Gyeongju 38066, Republic of Korea
| | - Sang Wook Kim
- Department of Advanced Materials Chemistry, Dongguk University, Gyeongju 38066, Republic of Korea
| | - Jae-Seon So
- Department of Medical Biotechnology, Dongguk University, Gyeongju 38066, Republic of Korea
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13
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Guarrochena X, Kronberger J, Tieber M, Ciesielski P, Mindt TL, Feiner IVJ. Straightforward Synthesis of DFO* - An Octadentate Chelator for Zirconium-89. ChemMedChem 2024; 19:e202300495. [PMID: 38102942 DOI: 10.1002/cmdc.202300495] [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: 09/15/2023] [Revised: 12/11/2023] [Accepted: 12/15/2023] [Indexed: 12/17/2023]
Abstract
DFO* is an octadentate chelator able to form highly stable chelates with Zirconium-89 (89 Zr) for nuclear medicinal applications in Positron Emission Tomography (PET).[1,2] The synthesis of DFO* and its scale-up remains challenging by reported synthetic protocols. For this reason, we set out to develop a de novo synthesis of a hydroxamate-containing building block suitable for the coupling to the commercially available DFO (desferrioxamine B, mesylate salt) yielding, after deprotection, the desired chelator DFO* in a more efficient procedure. Highlights of the new synthesis of DFO* reported herein are less synthetic steps and the isolation of the desired product DFO* by using solid phase extraction (SPE), thus avoiding tedious HPLC purification. DFO* is obtained in excellent purity (92-98 %) and an overall yield of approximately 29 %. In addition, the isolated trifluoroacetic acid (TFA)-salt of DFO* displays an improved solubility in organic solvents (DMSO, DMF, methanol), which will facilitate its use for the preparation of structurally diverse derivatives suitable for bioconjugation chemistry and the development of 89 Zr-labeled radiotracers.
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Affiliation(s)
- Xabier Guarrochena
- Bioinorganic Radiochemistry, Institute of Inorganic Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Strasse 42, 1090, Vienna, Austria
- Vienna Doctoral School in Chemistry, University of Vienna, Waehringer Strasse 42, 1090, Vienna, Austria
- Ludwig Boltzmann Institute Applied Diagnostics, AKH Wien c/o Sekretariat Nuklearmedizin, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Department of Biomedical Imaging and Image Guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Julia Kronberger
- Bioinorganic Radiochemistry, Institute of Inorganic Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Strasse 42, 1090, Vienna, Austria
- Vienna Doctoral School in Chemistry, University of Vienna, Waehringer Strasse 42, 1090, Vienna, Austria
- Ludwig Boltzmann Institute Applied Diagnostics, AKH Wien c/o Sekretariat Nuklearmedizin, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Department of Biomedical Imaging and Image Guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Manuel Tieber
- Bioinorganic Radiochemistry, Institute of Inorganic Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Strasse 42, 1090, Vienna, Austria
| | - Philipp Ciesielski
- ABX Advanced Biochemical Compounds, Heinrich-Glaeser-Strasse 10-14, 01454 Radeberg, Germany
| | - Thomas L Mindt
- Bioinorganic Radiochemistry, Institute of Inorganic Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Strasse 42, 1090, Vienna, Austria
- Ludwig Boltzmann Institute Applied Diagnostics, AKH Wien c/o Sekretariat Nuklearmedizin, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Department of Biomedical Imaging and Image Guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Joint Applied Medicinal Radiochemistry Facility, University of Vienna and Medical University of Vienna, Vienna, Austria
| | - Irene V J Feiner
- Bioinorganic Radiochemistry, Institute of Inorganic Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Strasse 42, 1090, Vienna, Austria
- Ludwig Boltzmann Institute Applied Diagnostics, AKH Wien c/o Sekretariat Nuklearmedizin, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Department of Biomedical Imaging and Image Guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
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14
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Yamaya T, Tashima H, Takyu S, Takahashi M. Whole Gamma Imaging: Challenges and Opportunities. PET Clin 2024; 19:83-93. [PMID: 37718218 DOI: 10.1016/j.cpet.2023.08.003] [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] [Indexed: 09/19/2023]
Abstract
Compton imaging has been recognized as a possible nuclear medicine imaging method following the establishment of SPECT and PET. Whole gamma imaging (WGI), a combination of PET and Compton imaging, could be the first practical method to bring out the potential of Compton imaging in nuclear medicine. With the use of such positron emitters as 89Zr and 44Sc, WGI may enable highly sensitive imaging of antibody drugs for early tumor detection and quantitative hypoxia imaging for effective tumor treatment. Some of these concepts have been demonstrated preliminarily in physics experiments and small animal imaging tests with a developed WGI prototype.
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Affiliation(s)
- Taiga Yamaya
- Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan.
| | - Hideaki Tashima
- Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Sodai Takyu
- Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Miwako Takahashi
- Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
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15
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Boswinkel M, Franssen GM, Heskamp S. Radiolabeled Antibodies for Immune Checkpoint PET in Preclinical Research. Methods Mol Biol 2024; 2729:143-158. [PMID: 38006495 DOI: 10.1007/978-1-0716-3499-8_9] [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] [Indexed: 11/27/2023]
Abstract
Antibodies that block immune checkpoints, also called immune checkpoint inhibitors (ICI), have demonstrated impressive anti-tumor efficacy. The success of ICIs results from a complex interplay between cancer cells and their immune microenvironment. One of the predictors for ICI efficacy is the expression of the targeted immune checkpoint, such as programmed death ligand 1 (PD-L1). Immune checkpoints can be expressed on tumor cells and/or subsets of immune cells. PET imaging offers unique possibilities to study the dynamics of immune checkpoint expression in tumor and normal tissues in a longitudinal manner. In this chapter, we describe the methodology to use zirconium-89-labeled antibodies to assess the expression of immune checkpoint molecules in syngeneic murine tumor models by PET imaging.
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Affiliation(s)
- Milou Boswinkel
- Department of Medical Imaging, Nuclear Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Gerben M Franssen
- Department of Medical Imaging, Nuclear Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Sandra Heskamp
- Department of Medical Imaging, Nuclear Medicine, Radboud University Medical Center, Nijmegen, The Netherlands.
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16
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Salih AK, Dominguez Garcia M, Raheem SJ, Ahiahonu WK, Price EW. DFO-Km: A Modular Chelator as a New Chemical Tool for the Construction of Zirconium-89-Based Radiopharmaceuticals. Inorg Chem 2023; 62:20806-20819. [PMID: 37751491 DOI: 10.1021/acs.inorgchem.3c02714] [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: 09/28/2023]
Abstract
Zirconium-89-labeled monoclonal antibodies and other large macromolecules such as nanoparticles hold great promise as positron emission tomography imaging agents. In general, zirconium-89 is an ideal radionuclide for long-circulating vectors such as antibodies or nanoparticles. It is also a promising radionuclide for theranostic radiopharmaceuticals due to its suitable match in half-life with actinium-225, thorium-227, lutetium-177, and others. As such, demand for new and optimized bifunctional chelators for zirconium-89 continues to grow. Herein, we present the modular chelator DFO-Km, which is octadentate and features lysine as a modular amino acid linker. The modular amino acid linker can be changed to other natural or unnatural amino acids to access different bioconjugation chemistries, while the chelating portion is unchanged thus retaining identical metal ion coordination properties to DFO-Km. The epsilon-amine in the DFO-Km linker (lysine) was used to complete synthesis of a bifunctional derivative bearing a p-SCN-Ph moiety. The chelator DFO-Km includes a redesigned hydroxamic acid, which provides more flexibility for metal ion coordination relative to the monomer used in the previously published DFO-Em. Moreover, a set of comprehensive DFT calculations were performed to model and evaluate 16 geometric isomers of Zr-(DFO-Km), which suggested the complex would form the optimum cic-cis-trans-trans octadentate Zr(IV) coordination geometry with no aqua or hydroxide ligands present. The bifunctional derivative p-SCN-Ph-DFO-Km was compared directly with the commercially available p-SCN-Ph-DFO, and both underwent efficient conjugation to a nonspecific human serum antibody (IgG) to yield two model immunoconjugates. The behavior of [89Zr]Zr-DFO-Km-IgG was studied in healthy mice for 2 weeks and compared to an equivalent cohort injected with [89Zr]Zr-DFO-IgG as a clinical "gold standard" control. PET-CT and biodistribution results revealed higher stability of [89Zr]Zr-(DFO-Km)-IgG in vivo over [89Zr]Zr-DFO-IgG, as demonstrated by the significant reduction of zirconium-89 in the whole skeleton as visualized and quantified by PET-CT at 1, 3, 7, and 14 days post-injection. Using CT-gated regions of interest over these PET-CT images, the whole skeleton was selected and uptake values were measured at 14 days post-injection of 3.6 ± 0.9 (DFO) vs 1.9 ± 0.1 (DFO-Km) %ID/g (n = 4, * p = 0.02), which represents a ∼48% reduction in bone uptake with DFO-Km relative to DFO. Biodistribution experiments performed on these same mice following the 14 day imaging time point revealed bone (both tibia) uptake values of 3.7 ± 1.3 (DFO) vs 2.0 ± 0.6 (DFO-Km) %ID/g (n = 6, * p < 0.05), with the tibia uptake values in close agreement with whole-skeleton ROI PET-CT data. These results indicate that DFO-Km is an improved chelator for [89Zr]Zr4+ applications relative to DFO. The bifunctional chelator p-SCN-Ph-DFO-Km shows potential as a new chemical tool for creating bioconjugates using targeting vectors such as antibodies, peptides, and nanoparticles.
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Affiliation(s)
- Akam K Salih
- Radiopharmacology, Mariana Oncology, Woburn, Massachusetts 01801, United States
| | - Moralba Dominguez Garcia
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan S7N-5C9, Canada
| | - Shvan J Raheem
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan S7N-5C9, Canada
| | - William K Ahiahonu
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan S7N-5C9, Canada
| | - Eric W Price
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan S7N-5C9, Canada
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17
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Mangeat T, Gracia M, Pichard A, Poty S, Martineau P, Robert B, Deshayes E. Fc-engineered monoclonal antibodies to reduce off-target liver uptake. EJNMMI Res 2023; 13:81. [PMID: 37697076 PMCID: PMC10495296 DOI: 10.1186/s13550-023-01030-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 08/28/2023] [Indexed: 09/13/2023] Open
Abstract
BACKGROUND Radiolabeled-antibodies usually display non-specific liver accumulation that may impair image analysis and antibody biodistribution. Here, we investigated whether Fc silencing influenced antibody biodistribution. We compared recombinant 89Zr-labeled antibodies (human IgG1 against different targets) with wild-type Fc and with mutated Fc (LALAPG triple mutation to prevent binding to Fc gamma receptors; FcγR). After antibody injection in mice harboring xenografts of different tumor cell lines or of immortalized human myoblasts, we analyzed antibody biodistribution by PET-CT and conventional biodistribution analysis. RESULTS Accumulation in liver was strongly reduced and tumor-specific targeting was increased for the antibodies with mutated Fc compared with wild-type Fc. CONCLUSION Antibodies with reduced binding to FcγR display lower liver accumulation and better tumor-to-liver ratios. These findings need to be taken into account to improve antibody-based theragnostic approaches.
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Affiliation(s)
- Tristan Mangeat
- Institut de Recherche en Cancérologie de Montpellier (IRCM), Inserm U1194, Université de Montpellier, ICM, 34298, Montpellier, France
| | - Matthieu Gracia
- Institut de Recherche en Cancérologie de Montpellier (IRCM), Inserm U1194, Université de Montpellier, ICM, 34298, Montpellier, France
| | - Alexandre Pichard
- Institut de Recherche en Cancérologie de Montpellier (IRCM), Inserm U1194, Université de Montpellier, ICM, 34298, Montpellier, France
| | - Sophie Poty
- Institut de Recherche en Cancérologie de Montpellier (IRCM), Inserm U1194, Université de Montpellier, ICM, 34298, Montpellier, France
| | - Pierre Martineau
- Institut de Recherche en Cancérologie de Montpellier (IRCM), Inserm U1194, Université de Montpellier, ICM, 34298, Montpellier, France
| | - Bruno Robert
- Institut de Recherche en Cancérologie de Montpellier (IRCM), Inserm U1194, Université de Montpellier, ICM, 34298, Montpellier, France.
- Institut de Recherche en Cancérologie de Montpellier (IRCM), 124 Avenue des Apothicaires, 34090, Montpellier, France.
| | - Emmanuel Deshayes
- Institut de Recherche en Cancérologie de Montpellier (IRCM), Inserm U1194, Université de Montpellier, ICM, 34298, Montpellier, France.
- Institut Régional du Cancer de Montpellier (ICM), Service de Médecine Nucléaire, 34298, Montpellier, France.
- Institut de Recherche en Cancérologie de Montpellier (IRCM), 124 Avenue des Apothicaires, 34090, Montpellier, France.
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18
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Wichmann CW, Poniger S, Guo N, Roselt P, Rudd SE, Donnelly PS, Blyth B, Van Zuylekom J, Rigopoulos A, Burvenich IJG, Morandeau L, Mohamed S, Nowak A, Hegi-Johnson F, MacManus M, Scott AM. Automated radiosynthesis of [ 89Zr]Zr-DFOSq-Durvalumab for imaging of PD-L1 expressing tumours in vivo. Nucl Med Biol 2023; 120-121:108351. [PMID: 37224789 DOI: 10.1016/j.nucmedbio.2023.108351] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 04/18/2023] [Accepted: 05/04/2023] [Indexed: 05/26/2023]
Abstract
OBJECTIVES 89Zr-labelled proteins are gaining importance in clinical research in a variety of diseases. To date, no clinical study has been reported that utilizes an automated approach for radiosynthesis of 89Zr-labelled radiopharmaceuticals. We aim to develop an automated method for the clinical production of 89Zr-labelled proteins and apply this method to Durvalumab, a monoclonal antibody targeting PD-L1 immune-checkpoint protein. PD-L1 expression is poorly understood and can be up-regulated over the course of chemo- and radiotherapy treatment. The ImmunoPET multicentre study aims to examine the dynamics of PD-L1 expression via 89Zr-Durvalumab PET imaging before, during, and after chemoradiotherapy. The developed automated technique will enable reproducible clinical production of [89Zr]Zr-DFOSq-Durvalumab for this study at three different sites. METHODS Conjugation of Durvalumab to H3DFOSqOEt was optimized for optimal chelator-to-antibody ratio. Automated radiolabelling of H3DFOSq-Durvalumab with zirconium-89 was optimized on the disposable cassette based iPHASE technologies MultiSyn radiosynthesizer using a modified cassette. Activity losses were tracked using a dose calibrator and minimized by optimizing fluid transfers, reaction buffer, antibody formulation additives and pH. The biological profile of the radiolabelled antibody was confirmed in vivo in PD-L1+ (HCC827) and PD-L1- (A549) murine xenografts. Clinical process validation and quality control were performed at three separate study sites to satisfy clinical release criteria. RESULTS H3DFOSq-Durvalumab with an average CAR of 3.02 was obtained. Radiolabelling kinetics in succinate (20 mM, pH 6) were significantly faster when compared to HEPES (0.5 M, pH 7.2) with >90 % conversion observed after 15 min. Residual radioactivity in the 89Zr isotope vial was reduced from 24 % to 0.44 % ± 0.18 % (n = 7) and losses in the reactor vial were reduced from 36 % ± 6 % (n = 4) to 0.82 % ± 0.75 % (n = 4) by including a surfactant in the reaction and formulation buffers. Overall process yield was 75 % ± 6 % (n = 5) and process time was 40 min. Typically, 165 MBq of [89Zr]Zr-DFOSq-Durvalumab with an apparent specific activity of 315 MBq/mg ± 34 MBq/mg (EOS) was obtained in a volume of 3.0 mL. At end-of-synthesis (EOS), radiochemical purity and protein integrity were always >99 % and >96 %, respectively, and dropped to 98 % and 65 % after incubation in human serum for 7 days at 37 °C. Immunoreactive fraction in HEK293/PD-L1 cells was 83.3 ± 9.0 (EOS). Preclinical in vivo data at 144 h p.i. showed excellent SUVmax in PD-L1+ tumour (8.32 ± 0.59) with a tumour-background ratio of 17.17 ± 3.96. [89Zr]Zr-DFOSq-Durvalumab passed all clinical release criteria at each study site and was deemed suitable for administration in a multicentre imaging trial. CONCLUSION Fully automated production of [89Zr]Zr-DFOSq-Durvalumab for clinical use was achieved with minimal exposure to the operator. The cassette-based approach allows for consecutive productions on the same day and offers an alternative to currently used manual protocols. The method should be broadly applicable to other proteins and has the potential for clinical impact considering the growing number of clinical trials investigating 89Zr-labelled antibodies.
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Affiliation(s)
- Christian W Wichmann
- Olivia Newton-John Cancer Research Institute, Heidelberg, VIC 3084, Australia; School of Cancer Medicine, La Trobe University, Bundoora, VIC 3083, Australia; Department of Molecular Imaging and Therapy, Austin Health, Heidelberg, VIC 3084, Australia; School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC 3052, Australia.
| | - Stan Poniger
- Department of Molecular Imaging and Therapy, Austin Health, Heidelberg, VIC 3084, Australia; iPHASE technologies Pty Ltd, Rowville, VIC 3178, Australia
| | - Nancy Guo
- Olivia Newton-John Cancer Research Institute, Heidelberg, VIC 3084, Australia
| | - Peter Roselt
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, VIC 3000, Australia; Peter MacCallum Cancer Centre, Melbourne, VIC 3000, Australia
| | - Stacey E Rudd
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC 3052, Australia
| | - Paul S Donnelly
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC 3052, Australia
| | - Benjamin Blyth
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, VIC 3000, Australia; Peter MacCallum Cancer Centre, Melbourne, VIC 3000, Australia
| | | | - Angela Rigopoulos
- Olivia Newton-John Cancer Research Institute, Heidelberg, VIC 3084, Australia
| | - Ingrid J G Burvenich
- Olivia Newton-John Cancer Research Institute, Heidelberg, VIC 3084, Australia; School of Cancer Medicine, La Trobe University, Bundoora, VIC 3083, Australia
| | - Laurence Morandeau
- Department of Medical Technology and Physics, Sir Charles Gairdner Hospital, Nedlands, WA 6009, Australia
| | - Shifaza Mohamed
- Department of Medical Technology and Physics, Sir Charles Gairdner Hospital, Nedlands, WA 6009, Australia
| | - Anna Nowak
- Office of Deputy Vice Chancellor (Research), University of Western Australia, Crawley, WA 6009, Australia
| | - Fiona Hegi-Johnson
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, VIC 3000, Australia; Peter MacCallum Cancer Centre, Melbourne, VIC 3000, Australia
| | - Michael MacManus
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, VIC 3000, Australia; Peter MacCallum Cancer Centre, Melbourne, VIC 3000, Australia
| | - Andrew M Scott
- Olivia Newton-John Cancer Research Institute, Heidelberg, VIC 3084, Australia; School of Cancer Medicine, La Trobe University, Bundoora, VIC 3083, Australia; Department of Molecular Imaging and Therapy, Austin Health, Heidelberg, VIC 3084, Australia; Faculty of Medicine, The University of Melbourne, VIC 3000, Australia
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19
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Morath V, Brandt C, Deuschle FC, Mendler CT, Blechert B, Summer D, Barinka C, Decristoforo C, Weber WA, Schwaiger M, Skerra A. Molecular Design of 68Ga- and 89Zr-Labeled Anticalin Radioligands for PET-Imaging of PSMA-Positive Tumors. Mol Pharm 2023; 20:2490-2501. [PMID: 37068305 DOI: 10.1021/acs.molpharmaceut.2c01066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
Abstract
Anticalin proteins directed against the prostate-specific membrane antigen (PSMA), optionally having tailored plasma half-life using PASylation technology, show promise as radioligands for PET-imaging of xenograft tumors in mice. To investigate their suitability, the short-circulating unmodified Anticalin was labeled with 68Ga (τ1/2 = 68 min), using the NODAGA chelator, whereas the half-life extended PASylated Anticalin was labeled with 89Zr (τ1/2 = 78 h), using either the linear chelator deferoxamine (Dfo) or a cyclic derivative, fusarinine C (FsC). Different PSMA targeting Anticalin versions (optionally carrying the PASylation sequence) were produced carrying a single exposed N- or C-terminal Cys residue and site-specifically conjugated with the different radiochelators via maleimide chemistry. These protein conjugates were labeled with radioisotopes having distinct physical half-lives and, subsequently, applied for PET-imaging of subcutaneous LNCaP xenograft tumors in CB17 SCID mice. Uptake of the protein tracers into tumor versus healthy tissues was assessed by segmentation of PET data as well as biodistribution analyses. PET-imaging with both the 68Ga-labeled plain Anticalin and the 89Zr-labeled PASylated Anticalin allowed clear delineation of the xenograft tumor. The radioligand A3A5.1-PAS(200)-FsC·89Zr, having an extended plasma half-life, led to a higher tumor uptake 24 h p.i. compared to the 68Ga·NODAGA-Anticalin imaged 60 min p.i. (2.5% ID/g vs 1.2% ID/g). Pronounced demetallation was observed for the 89Zr·Dfo-labeled PASylated Anticalin, which was ∼50% lower in the case of the cyclic radiochelator FsC (p < 0.0001). Adjusting the plasma half-life of Anticalin radioligands using PASylation technology is a viable approach to increase radioisotope accumulation within the tumor. Furthermore, 89Zr-ImmunoPET-imaging using the FsC radiochelator is superior to that using Dfo. Our strategy for the half-life adjustment of a tumor-targeting Anticalin to match the physical half-life of the applied radioisotope illustrates the potential of small binding proteins as an alternative to antibodies for PET-imaging.
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Affiliation(s)
- Volker Morath
- Department of Nuclear Medicine, Klinikum rechts der Isar, School of Medicine, Technical University of Munich, Munich 81675, Germany
- Lehrstuhl für Biologische Chemie, School of Life Sciences, Technical University of Munich, Freising 85354, Germany
| | - Corinna Brandt
- Lehrstuhl für Biologische Chemie, School of Life Sciences, Technical University of Munich, Freising 85354, Germany
| | - Friedrich-Christian Deuschle
- Lehrstuhl für Biologische Chemie, School of Life Sciences, Technical University of Munich, Freising 85354, Germany
| | - Claudia T Mendler
- Department of Nuclear Medicine, Klinikum rechts der Isar, School of Medicine, Technical University of Munich, Munich 81675, Germany
| | - Birgit Blechert
- Department of Nuclear Medicine, Klinikum rechts der Isar, School of Medicine, Technical University of Munich, Munich 81675, Germany
| | - Dominik Summer
- Department of Nuclear Medicine, Medical University Innsbruck, Innsbruck 6020, Austria
| | - Cyril Barinka
- Laboratory of Structural Biology, Institute of Biotechnology, Czech Academy of Sciences, Vestec 252 50, Czech Republic
| | - Clemens Decristoforo
- Department of Nuclear Medicine, Medical University Innsbruck, Innsbruck 6020, Austria
| | - Wolfgang A Weber
- Department of Nuclear Medicine, Klinikum rechts der Isar, School of Medicine, Technical University of Munich, Munich 81675, Germany
| | - Markus Schwaiger
- Department of Nuclear Medicine, Klinikum rechts der Isar, School of Medicine, Technical University of Munich, Munich 81675, Germany
| | - Arne Skerra
- Lehrstuhl für Biologische Chemie, School of Life Sciences, Technical University of Munich, Freising 85354, Germany
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20
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Stergiou N, Wuensche TE, Schreurs M, Mes I, Verlaan M, Kooijman EJM, Windhorst AD, Helboe L, Vergo S, Christensen S, Asuni AA, Jensen A, Van Dongen GAMS, Bang-Andersen B, Vugts DJ, Beaino W. Application of 89Zr-DFO*-immuno-PET to assess improved target engagement of a bispecific anti-amyloid-ß monoclonal antibody. Eur J Nucl Med Mol Imaging 2023; 50:1306-1317. [PMID: 36635462 PMCID: PMC10027647 DOI: 10.1007/s00259-023-06109-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 01/05/2023] [Indexed: 01/14/2023]
Abstract
PURPOSE The recent conditional FDA approval of Aducanumab (Adu) for treating Alzheimer's disease (AD) and the continued discussions around that decision have increased interest in immunotherapy for AD and other brain diseases. Reliable techniques for brain imaging of antibodies may guide decision-making in the future but needs further development. In this study, we used 89Zr-immuno-PET to evaluate the targeting and distribution of a bispecific brain-shuttle IgG based on Adu with transferrin receptor protein-1 (TfR1) shuttling mechanism, mAbAdu-scFab8D3, designated Adu-8D3, as a candidate theranostic for AD. We also validated the 89Zr-immuno-PET platform as an enabling technology for developing new antibody-based theranostics for brain disorders. METHODS Adu, Adu-8D3, and the non-binding control construct B12-8D3 were modified with DFO*-NCS and radiolabeled with 89Zr. APP/PS1 mice were injected with 89Zr-labeled mAbs and imaged on days 3 and 7 by positron emission tomography (PET). Ex vivo biodistribution was performed on day 7, and ex vivo autoradiography and immunofluorescence staining were done on brain tissue to validate the PET imaging results and target engagement with amyloid-β plaques. Additionally, [89Zr]Zr-DFO*-Adu-8D3 was evaluated in 3, 7, and 10-month-old APP/PS1 mice to test its potential in early stage disease. RESULTS A 7-fold higher brain uptake was observed for [89Zr]Zr-DFO*-Adu-8D3 compared to [89Zr]Zr-DFO*-Adu and a 2.7-fold higher uptake compared to [89Zr]Zr-DFO*-B12-8D3 on day 7. Autoradiography and immunofluorescence of [89Zr]Zr-DFO*-Adu-8D3 showed co-localization with amyloid plaques, which was not the case with the Adu and B12-8D3 conjugates. [89Zr]Zr-DFO*-Adu-8D3 was able to detect low plaque load in 3-month-old APP/PS1 mice. CONCLUSION 89Zr-DFO*-immuno-PET revealed high and specific uptake of the bispecific Adu-8D3 in the brain and can be used for the early detection of Aβ plaque pathology. Here, we demonstrate that 89Zr-DFO*-immuno-PET can be used to visualize and quantify brain uptake of mAbs and contribute to the evaluation of biological therapeutics for brain diseases.
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Affiliation(s)
- N Stergiou
- Radiology & Nuclear Medicine, Amsterdam UMC location Vrije Universiteit Amsterdam, de Boelelaan 1117, Amsterdam, The Netherlands
| | - T E Wuensche
- Radiology & Nuclear Medicine, Amsterdam UMC location Vrije Universiteit Amsterdam, de Boelelaan 1117, Amsterdam, The Netherlands
| | - M Schreurs
- Radiology & Nuclear Medicine, Amsterdam UMC location Vrije Universiteit Amsterdam, de Boelelaan 1117, Amsterdam, The Netherlands
| | - I Mes
- Radiology & Nuclear Medicine, Amsterdam UMC location Vrije Universiteit Amsterdam, de Boelelaan 1117, Amsterdam, The Netherlands
| | - M Verlaan
- Radiology & Nuclear Medicine, Amsterdam UMC location Vrije Universiteit Amsterdam, de Boelelaan 1117, Amsterdam, The Netherlands
| | - E J M Kooijman
- Radiology & Nuclear Medicine, Amsterdam UMC location Vrije Universiteit Amsterdam, de Boelelaan 1117, Amsterdam, The Netherlands
| | - A D Windhorst
- Radiology & Nuclear Medicine, Amsterdam UMC location Vrije Universiteit Amsterdam, de Boelelaan 1117, Amsterdam, The Netherlands
| | - L Helboe
- H. Lundbeck A/S, Copenhagen, Denmark
| | - S Vergo
- H. Lundbeck A/S, Copenhagen, Denmark
| | | | - A A Asuni
- H. Lundbeck A/S, Copenhagen, Denmark
| | - A Jensen
- H. Lundbeck A/S, Copenhagen, Denmark
| | - G A M S Van Dongen
- Radiology & Nuclear Medicine, Amsterdam UMC location Vrije Universiteit Amsterdam, de Boelelaan 1117, Amsterdam, The Netherlands
| | | | - D J Vugts
- Radiology & Nuclear Medicine, Amsterdam UMC location Vrije Universiteit Amsterdam, de Boelelaan 1117, Amsterdam, The Netherlands
| | - W Beaino
- Radiology & Nuclear Medicine, Amsterdam UMC location Vrije Universiteit Amsterdam, de Boelelaan 1117, Amsterdam, The Netherlands.
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21
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Koehler C, Sauter PF, Klasen B, Waldmann C, Pektor S, Bausbacher N, Lemke EA, Miederer M. Genetic Code Expansion for Site-Specific Labeling of Antibodies with Radioisotopes. ACS Chem Biol 2023; 18:443-448. [PMID: 36889678 PMCID: PMC10029752 DOI: 10.1021/acschembio.2c00634] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 02/27/2023] [Indexed: 03/10/2023]
Abstract
Due to their target specificity, antibody-drug conjugates─monoclonal antibodies conjugated to a cytotoxic moiety─are efficient therapeutics that can kill malignant cells overexpressing a target gene. Linking an antibody with radioisotopes (radioimmunoconjugates) enables powerful diagnostics and/or closely related therapeutic applications, depending on the isotope. To generate site-specific radioimmunoconjugates, we utilized genetic code expansion and subsequent conjugation by inverse electron-demand Diels-Alder cycloaddition reactions. We show that, using this approach, site-specific labeling of trastuzumab with either zirconium-89 (89Zr) for diagnostics or lutetium-177 (177Lu) for therapeutics yields efficient radioimmunoconjugates. Positron emission tomography imaging revealed a high accumulation of site-specifically 89Zr-labeled trastuzumab in tumors after 24 h and low accumulation in other organs. The corresponding 177Lu-trastuzumab radioimmunoconjugates were comparably distributed in vivo.
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Affiliation(s)
- Christine Koehler
- VERAXA
Biotech GmbH, Carl-Friedrich
Gauß-Ring 5, 69124 Heidelberg, Germany
- Structural
and Computational Biology Unit, European
Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Paul F. Sauter
- VERAXA
Biotech GmbH, Carl-Friedrich
Gauß-Ring 5, 69124 Heidelberg, Germany
- Structural
and Computational Biology Unit, European
Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Benedikt Klasen
- Department
of Chemistry, TRIGA site, Johannes Gutenberg
University, Fritz-Strassmann-Weg 2, 55128 Mainz, Germany
| | - Christopher Waldmann
- Department
of Nuclear Medicine, University Medical
Center, Johannes Gutenberg University Langenbeckstraße 1, 55131 Mainz, Germany
| | - Stefanie Pektor
- Department
of Nuclear Medicine, University Medical
Center, Johannes Gutenberg University Langenbeckstraße 1, 55131 Mainz, Germany
| | - Nicole Bausbacher
- Department
of Nuclear Medicine, University Medical
Center, Johannes Gutenberg University Langenbeckstraße 1, 55131 Mainz, Germany
| | - Edward A. Lemke
- BIOCENTER, Johannes Gutenberg University, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany
- IMB
Institute
of Molecular Biology, gGmbH, Ackermannweg 4, 55128 Mainz, Germany
| | - Matthias Miederer
- Department
of Nuclear Medicine, University Medical
Center, Johannes Gutenberg University Langenbeckstraße 1, 55131 Mainz, Germany
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22
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Chakravarty R, Rohra N, Jadhav S, Sarma HD, Jain R, Chakraborty S. Biochemical separation of Cetuximab-Fab from papain-digested antibody fragments and radiolabeling with 64Cu for potential use in radioimmunotheranostics. Appl Radiat Isot 2023; 196:110795. [PMID: 37004293 DOI: 10.1016/j.apradiso.2023.110795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 03/09/2023] [Accepted: 03/27/2023] [Indexed: 03/29/2023]
Abstract
Engineered Fab fragments of monoclonal antibodies (mAbs) after radiolabeling with suitable radiometals have the potential to play a key role in personalized radioimmunotheranostics of cancer patients. In this study, we have generated Fab fragment of Cetuximab, a mAb targeting epidermal growth factor receptor (EGFR) expression and purified from the Fc and other fragments by ultrafiltration and affinity chromatography. The Cetuximab-Fab was conjugated with a suitable bifunctional chelator and radiolabeled with no-carrier-added (NCA) 64Cu produced via 64Zn (n, p) 64Cu reaction in a nuclear reactor. The radioimmunoconjugate obtained after size exclusion chromatographic separation possessed >95% radiochemical purity and it retained its integrity over at least three half-lives of the radiometal. Biodistribution studies was performed in fibrosarcoma tumor bearing Swiss mice, which demonstrated the explicit need for purification of the Cetuximab-Fab from Fc fragments. Enhanced and rapid tumor uptake with decent tumor-to-background ratio with prolonged retention was observed when radiolabeled purified Cetuximab-Fab was intravenously administered in animal models. Overall, this preclinical study established the pivotal role of separation science and technology to obtain the radioimmunoconjugate with requisite purity in order to demonstrate optimal pharmacokinetics and maximized treatment efficacy.
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23
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Melendez-Alafort L, Ferro-Flores G, De Nardo L, Ocampo-García B, Bolzati C. Zirconium immune-complexes for PET molecular imaging: Current status and prospects. Coord Chem Rev 2023. [DOI: 10.1016/j.ccr.2022.215005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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24
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Khozeimeh Sarbisheh E, Summers KL, Salih AK, Cotelesage JJH, Zimmerling A, Pickering IJ, George GN, Price EW. Radiochemical, Computational, and Spectroscopic Evaluation of High-Denticity Desferrioxamine Derivatives DFO2 and DFO2p toward an Ideal Zirconium-89 Chelate Platform. Inorg Chem 2023; 62:2637-2651. [PMID: 36716427 DOI: 10.1021/acs.inorgchem.2c03573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Desferrioxamine (DFO) has long been considered the gold standard chelator for incorporating [89Zr]Zr4+ in radiopharmaceuticals for positron emission tomography (PET) imaging. To improve the stability of DFO with zirconium-89 and to expand its coordination sphere to enable binding of large therapeutic radiometals, we have synthesized the highest denticity DFO derivatives to date: dodecadentate DFO2 and DFO2p. In this study, we describe the synthesis and characterization of a novel DFO-based chelator, DFO2p, which is comprised of two DFO strands connected by an p-NO2-phenyl linker and therefore contains double the chelating moieties of DFO (potential coordination number up to 12 vs 6). The chelator DFO2p offers an optimized synthesis comprised of only a single reaction step and improves water solubility relative to DFO2, but the shorter linker reduces molecular flexibility. Both DFO2 and DFO2p, each with 6 potential hydroxamate ligands, are able to reach a more energetically favorable 8-coordinate environment for Zr(IV) than DFO. The zirconium(IV) coordination environment of these complexes were evaluated by a combination of density functional theory (DFT) calculations and synchrotron spectroscopy (extended X-ray absorption fine structure), which suggest the inner-coordination sphere of zirconium(IV) to be comprised of the outermost four hydroxamate ligands. These results also confirm a single Zr(IV) in each chelator, and the hydroxide ligands which complete the coordination sphere of Zr(IV)-DFO are absent from Zr(IV)-DFO2 and Zr(IV)-DFO2p. Radiochemical stability studies with zirconium-89 revealed the order of real-world stability to be DFO2 > DFO2p ≫ DFO. The zirconium-89 complexes of these new high-denticity chelators were found to be far more stable than DFO, and the decreased molecular flexibility of DFO2p, relative to DFO2, could explain its decreased stability, relative to DFO2.
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Affiliation(s)
- Elaheh Khozeimeh Sarbisheh
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, Saskatoon, SKS7N 5C9, Canada
| | - Kelly L Summers
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, Saskatoon, SKS7N 5C9, Canada.,Molecular and Environmental Science Group, Department of Geological Sciences, College of Arts and Science, University of Saskatchewan, Saskatoon, SKS7N 5E2, Canada
| | - Akam K Salih
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, Saskatoon, SKS7N 5C9, Canada
| | - Julien J H Cotelesage
- Molecular and Environmental Science Group, Department of Geological Sciences, College of Arts and Science, University of Saskatchewan, Saskatoon, SKS7N 5E2, Canada
| | - Amanda Zimmerling
- Division of Biomedical Engineering, College of Engineering, University of Saskatchewan, Saskatoon, SKS7N 5A9, Canada
| | - Ingrid J Pickering
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, Saskatoon, SKS7N 5C9, Canada.,Molecular and Environmental Science Group, Department of Geological Sciences, College of Arts and Science, University of Saskatchewan, Saskatoon, SKS7N 5E2, Canada
| | - Graham N George
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, Saskatoon, SKS7N 5C9, Canada.,Molecular and Environmental Science Group, Department of Geological Sciences, College of Arts and Science, University of Saskatchewan, Saskatoon, SKS7N 5E2, Canada
| | - Eric W Price
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, Saskatoon, SKS7N 5C9, Canada
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25
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Choi PS, Lee JY, Chae JH, Wadas T, Cheng Z, Hur MG, Park JH. Theranostics through Utilizing Cherenkov Radiation of Radioisotope Zr-89 with a Nanocomposite Combination of TiO 2 and MnO 2. ACS APPLIED MATERIALS & INTERFACES 2023; 15:3689-3698. [PMID: 36573583 DOI: 10.1021/acsami.2c09195] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Cherenkov radiation (CR) derived from the decay of diagnostic and therapeutic radionuclides is currently being studied by the scientific community to determine if these emissions can be harnessed for cancer detection and therapy. While Cherenkov luminescence imaging (CLI) has been studied in the preclinical and clinical settings, Cherenkov radiation-induced cancer therapy (CRICT) is a relatively new area of research that harnesses the emitted photons to kill cancer cells through free radical generation and DNA damage. Nanoparticles seem well suited for developing a theranostic platform that would allow researchers to visualize therapy delivery and also generate the reactive oxygen species necessary to kill cancer cells. Herein, we report the preparation of an 89Zr-TiO2-MnO2 nanocomposite that incorporates transferrin onto the nanoparticle surface to enhance cancer cell growth inhibition. The incorporation of the positron emission tomography (PET) radioisotope 89Zr (half-life: 3.3 days) allowed for the detection of the nanoparticle using PET and for the creation of Cherenkov emissions that interacted with the nanoparticle surface to generate free radicals for therapy delivery. After preparation, these systems were observed to be stable in various media and provided excellent tumor growth control after being intratumorally injected into mice bearing CT-26 tumors. These results demonstrate that a therapeutically efficient CRICT platform can be generated using commercially available and affordable materials.
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Affiliation(s)
- Pyeong Seok Choi
- Accelerator Radioisotope Development Team, Korea Atomic Energy Research Institute, Jeongeup Si, Jeollabuk Do 56212, Republic of Korea
| | - Jun Young Lee
- Accelerator Radioisotope Development Team, Korea Atomic Energy Research Institute, Jeongeup Si, Jeollabuk Do 56212, Republic of Korea
| | - Jung Ho Chae
- Accelerator Radioisotope Development Team, Korea Atomic Energy Research Institute, Jeongeup Si, Jeollabuk Do 56212, Republic of Korea
| | - Thaddeus Wadas
- Department of Radiology, Carver College of Medicine, University of Iowa, 169 Newton Road, Iowa City, Iowa 52242, United States
| | - Zhen Cheng
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Min Goo Hur
- Radiation Utilization and Facilities Management Division, Korea Atomic Energy Research Institute, Jeongeup Si, Jeollabuk Do 56212, Republic of Korea
| | - Jeong Hoon Park
- Accelerator Radioisotope Development Team, Korea Atomic Energy Research Institute, Jeongeup Si, Jeollabuk Do 56212, Republic of Korea
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26
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Preclinical development of ZED8, an 89Zr immuno-PET reagent for monitoring tumor CD8 status in patients undergoing cancer immunotherapy. Eur J Nucl Med Mol Imaging 2023; 50:287-301. [PMID: 36271158 DOI: 10.1007/s00259-022-05968-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 09/11/2022] [Indexed: 01/10/2023]
Abstract
BACKGROUND ZED8 is a novel monovalent antibody labeled with zirconium-89 for the molecular imaging of CD8. This work describes nonclinical studies performed in part to provide rationale for and to inform expectations in the early clinical development of ZED8, such as in the studies outlined in clinical trial registry NCT04029181 [1]. METHODS Surface plasmon resonance, X-ray crystallography, and flow cytometry were used to characterize the ZED8-CD8 binding interaction, its specificity, and its impact on T cell function. Immuno-PET with ZED8 was assessed in huCD8+ tumor-bearing mice and in non-human primates. Plasma antibody levels were measured by ELISA to determine pharmacokinetic parameters, and OLINDA 1.0 was used to estimate radiation dosimetry from image-derived biodistribution data. RESULTS ZED8 selectively binds to human CD8α at a binding site approximately 9 Å from that of MHCI making mutual interference unlikely. The equilibrium dissociation constant (KD) is 5 nM. ZED8 binds to cynomolgus CD8 with reduced affinity (66 nM) but it has no measurable affinity for rat or mouse CD8. In a series of lymphoma xenografts, ZED8 imaging was able to identify different CD8 levels concordant with flow cytometry. In cynomolgus monkeys with tool compound 89Zr-aCD8v17, lymph nodes were conspicuous by imaging 24 h post-injection, and the pharmacokinetics suggested a flat-fixed first-in-human dose of 4 mg per subject. The whole-body effective dose for an adult human was estimated to be 0.48 mSv/MBq, comparable to existing 89Zr immuno-PET reagents. CONCLUSION 89Zr immuno-PET with ZED8 appears to be a promising biomarker of tissue CD8 levels suitable for clinical evaluation in cancer patients eligible for immunotherapy.
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89Zr-labelled Obinutuzumab: a potential immuno-PET radiopharmaceutical. J Radioanal Nucl Chem 2022. [DOI: 10.1007/s10967-022-08614-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Bubenshchikov VB, Larenkov AA. Chelating Agents for Zirconium-89 in the Synthesis of Radiopharmaceuticals: Current State and Prospects of Development. RUSS J COORD CHEM+ 2022. [DOI: 10.1134/s1070328422110021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Wuensche TE, Stergiou N, Mes I, Verlaan M, Schreurs M, Kooijman EJM, Janssen B, Windhorst AD, Jensen A, Asuni AA, Bang-Andersen B, Beaino W, Dongen GAMS, Vugts DJ. Advancing 89Zr-immuno-PET in neuroscience with a bispecific anti-amyloid-beta monoclonal antibody - The choice of chelator is essential. Theranostics 2022; 12:7067-7079. [PMID: 36276653 PMCID: PMC9576608 DOI: 10.7150/thno.73509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 08/27/2022] [Indexed: 11/05/2022] Open
Abstract
The accelerated approval of the monoclonal antibody (mAb) aducanumab as a treatment option for Alzheimer's Disease and the continued discussions about its efficacy have shown that a better understanding of immunotherapy for the treatment of neurodegenerative diseases is needed. 89Zr-immuno-PET could be a suitable tool to open new avenues for the diagnosis of CNS disorders, monitoring disease progression, and assessment of novel therapeutics. Herein, three different 89Zr-labeling strategies and direct radioiodination with 125I of a bispecific anti-amyloid-beta aducanumab derivate, consisting of aducanumab with a C-terminal fused anti-transferrin receptor binding single chain Fab fragment derived from 8D3 (Adu-8D3), were compared ex vivo and in vivo with regard to brain uptake and target engagement in an APP/PS1 Alzheimer's disease mouse model and wild type animals. Methods: Adu-8D3 and a negative control antibody, based on the HIV specific B12 antibody also carrying C-terminal fused 8D3 scFab (B12-8D3), were each conjugated with NCS-DFO, NCS-DFO*, or TFP-N-suc-DFO-Fe-ester, followed by radiolabeling with 89Zr. 125I was used as a substitute for 124I for labeling of both antibodies. 30 µg of radiolabeled mAb, corresponding to approximately 6 MBq 89Zr or 2.5 MBq 125I, were injected per mouse. PET imaging was performed 1, 3 and 7 days post injection (p.i.). All mice were sacrificed on day 7 p.i. and subjected to ex vivo biodistribution and brain autoradiography. Immunostaining on brain tissue was performed after autoradiography for further validation. Results:Ex vivo biodistribution revealed that the brain uptake of [89Zr]Zr-DFO*-NCS-Adu-8D3 (2.19 ±0.12 %ID/g) was as high as for its 125I-analog (2.21 ±0.15 %ID/g). [89Zr]Zr-DFO-NCS-Adu-8D3 and [89Zr]Zr-DFO-N-suc-Adu-8D3 showed significantly lower uptake (< 0.65 %ID/g), being in the same range as for the 89Zr-labeled controls (B12-8D3). Autoradiography of [89Zr]Zr-DFO*-NCS-Adu-8D3 and [125I]I-Adu-8D3 showed an amyloid-beta related granular uptake pattern of radioactivity. In contrast, the [89Zr]Zr-DFO-conjugates and the control antibody groups did not show any amyloid-beta related uptake pattern, indicating that DFO is inferior for 89Zr-immuno-PET imaging of the brain in comparison to DFO* for Adu-8D3. This was confirmed by day 7 PET images showing only amyloid-beta related brain uptake for [89Zr]Zr-DFO*-NCS-Adu-8D3. In wild type animals, such an uptake was not observed. Immunostaining showed a co-localization of all administered Adu-8D3 conjugates with amyloid-beta plaques. Conclusion: We successfully demonstrated that 89Zr-immuno-PET is suitable for imaging and quantifying amyloid-beta specific brain uptake using a bispecific aducanumab brain shuttling antibody, Adu-8D3, but only when using the novel chelator DFO*, and not DFO, for labeling with 89Zr.
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Affiliation(s)
- Thomas E Wuensche
- Amsterdam UMC location Vrije Universiteit Amsterdam, dept Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, The Netherlands
| | - Natascha Stergiou
- Amsterdam UMC location Vrije Universiteit Amsterdam, dept Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, The Netherlands
| | - Iris Mes
- Amsterdam UMC location Vrije Universiteit Amsterdam, dept Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, The Netherlands
| | - Mariska Verlaan
- Amsterdam UMC location Vrije Universiteit Amsterdam, dept Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, The Netherlands
| | - Maxime Schreurs
- Amsterdam UMC location Vrije Universiteit Amsterdam, dept Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, The Netherlands
| | - Esther J M Kooijman
- Amsterdam UMC location Vrije Universiteit Amsterdam, dept Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, The Netherlands
| | - Bart Janssen
- Amsterdam UMC location Vrije Universiteit Amsterdam, dept Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, The Netherlands
| | - Albert D Windhorst
- Amsterdam UMC location Vrije Universiteit Amsterdam, dept Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, The Netherlands.,Amsterdam Neuroscience, Brain imaging, Amsterdam, The Netherlands
| | - Allan Jensen
- H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| | | | | | - Wissam Beaino
- Amsterdam UMC location Vrije Universiteit Amsterdam, dept Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, The Netherlands.,Amsterdam Neuroscience, Brain imaging, Amsterdam, The Netherlands
| | - Guus A M S Dongen
- Amsterdam UMC location Vrije Universiteit Amsterdam, dept Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, The Netherlands.,Amsterdam Neuroscience, Brain imaging, Amsterdam, The Netherlands
| | - Danielle J Vugts
- Amsterdam UMC location Vrije Universiteit Amsterdam, dept Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, The Netherlands.,Amsterdam Neuroscience, Brain imaging, Amsterdam, The Netherlands
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Guo R, Xue S, Hu J, Sari H, Mingels C, Zeimpekis K, Prenosil G, Wang Y, Zhang Y, Viscione M, Sznitman R, Rominger A, Li B, Shi K. Using domain knowledge for robust and generalizable deep learning-based CT-free PET attenuation and scatter correction. Nat Commun 2022; 13:5882. [PMID: 36202816 PMCID: PMC9537165 DOI: 10.1038/s41467-022-33562-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 09/22/2022] [Indexed: 11/16/2022] Open
Abstract
Despite the potential of deep learning (DL)-based methods in substituting CT-based PET attenuation and scatter correction for CT-free PET imaging, a critical bottleneck is their limited capability in handling large heterogeneity of tracers and scanners of PET imaging. This study employs a simple way to integrate domain knowledge in DL for CT-free PET imaging. In contrast to conventional direct DL methods, we simplify the complex problem by a domain decomposition so that the learning of anatomy-dependent attenuation correction can be achieved robustly in a low-frequency domain while the original anatomy-independent high-frequency texture can be preserved during the processing. Even with the training from one tracer on one scanner, the effectiveness and robustness of our proposed approach are confirmed in tests of various external imaging tracers on different scanners. The robust, generalizable, and transparent DL development may enhance the potential of clinical translation. Deep learning-based methods have been proposed to substitute CT-based PET attenuation and scatter correction to achieve CT-free PET imaging. Here, the authors present a simple way to integrate domain knowledge in deep learning for CT-free PET imaging.
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Affiliation(s)
- Rui Guo
- Department of Nuclear Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Collaborative Innovation Center for Molecular Imaging of Precision Medicine, Ruijin Center, Shanghai, China
| | - Song Xue
- Department of Nuclear Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Jiaxi Hu
- Department of Nuclear Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Hasan Sari
- Department of Nuclear Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.,Advanced Clinical Imaging Technology, Siemens Healthcare AG, Lausanne, Switzerland
| | - Clemens Mingels
- Department of Nuclear Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Konstantinos Zeimpekis
- Department of Nuclear Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - George Prenosil
- Department of Nuclear Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Yue Wang
- Department of Nuclear Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Collaborative Innovation Center for Molecular Imaging of Precision Medicine, Ruijin Center, Shanghai, China
| | - Yu Zhang
- Department of Nuclear Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Collaborative Innovation Center for Molecular Imaging of Precision Medicine, Ruijin Center, Shanghai, China
| | - Marco Viscione
- Department of Nuclear Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Raphael Sznitman
- ARTORG Center, University of Bern, Bern, Switzerland.,Center of Artificial Intelligence in Medicine (CAIM), University of Bern, Bern, Switzerland
| | - Axel Rominger
- Department of Nuclear Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Biao Li
- Department of Nuclear Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China. .,Collaborative Innovation Center for Molecular Imaging of Precision Medicine, Ruijin Center, Shanghai, China.
| | - Kuangyu Shi
- Department of Nuclear Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.,Center of Artificial Intelligence in Medicine (CAIM), University of Bern, Bern, Switzerland.,Computer Aided Medical Procedures and Augmented Reality, Institute of Informatics I16, Technical University of Munich, Munich, Germany
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Allen KJH, Jiao R, Li J, Beckford-Vera DR, Dadachova E. In Vitro and In Vivo Characterization of 89Zirconium-Labeled Lintuzumab Molecule. Molecules 2022; 27:molecules27196589. [PMID: 36235126 PMCID: PMC9571394 DOI: 10.3390/molecules27196589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/27/2022] [Accepted: 09/30/2022] [Indexed: 11/13/2022] Open
Abstract
Objective: Positron emission tomography (PET) imaging is a powerful non-invasive method to determine the in vivo behavior of biomolecules. Determining biodistribution and pharmacokinetic (PK) properties of targeted therapeutics can enable a better understanding of in vivo drug mechanisms such as tumor uptake, off target accumulation and clearance. Zirconium-89 (89Zr) is a readily available tetravalent PET-enabling radiometal that has been used to evaluate the biodistribution and PK of monoclonal antibodies. In the current study, we performed in vitro and in vivo characterization of 89Zr-lintuzumab, a radiolabeled anti-CD33 antibody, as a model to evaluate the in vivo binding properties in preclinical models of AML. Methods: Lintuzumab was conjugated to p-SCN-Bn-deferoxamine (DFO) and labeled with 89Zr using a 5:1 µCi:µg specific activity at 37 °C for 1h. The biological activity of 89Zr-lintuzumab was evaluated in a panel of CD33 positive cells using flow cytometry. Fox Chase SCID mice were injected with 2 × 106 OCI-AML3 cells into the right flank. After 12 days, a cohort of mice (n = 4) were injected with 89Zr-lintuzumab via tail vein. PET/CT scans of mice were acquired on days 1, 2, 3 and 7 post 89Zr-lintuzumab injection. To demonstrate 89Zr-lintuzumab specific binding to CD33 expressing tumors in vivo, a blocking study was performed. This cohort of mice (n = 4) was injected with native lintuzumab and 24 h later 89Zr-lintuzumab was administered. This group was imaged 3 and 7 days after injection of 89Zr-lintuzumab. A full ex vivo biodistribution study on both cohorts was performed on day 7. The results from the PET image and ex vivo biodistribution studies were compared. Results: Lintuzumab was successfully radiolabeled with 89Zr resulting in a 99% radiochemical yield. The 89Zr-lintuzumab radioconjugate specifically binds CD33 positive cells in a similar manner to native lintuzumab as observed by flow cytometry. PET imaging revealed high accumulation of 89Zr-lintuzumab in OCI-AML3 tumors within 24h post-injection of the radioconjugate. The 89Zr-lintuzumab high tumor uptake remains for up to 7 days. Tumor analysis of the PET data using volume of interest (VOI) showed significant blocking of 89Zr-lintuzumab in the group pre-treated with native lintuzumab (pre-blocked group), thus indicating specific targeting of CD33 on OCI-AML3 cells in vivo. The tumor uptake findings from the PET imaging study are in agreement with those from the ex vivo biodistribution results. Conclusions: PET imaging of 89Zr-lintuzumab shows high specific uptake in CD33 positive human OCI-AML3 tumors. The results from the image study agree with the observations from the ex vivo biodistribution study. Our findings collectively suggest that PET imaging using 89Zr-lintuzumab could be a powerful drug development tool to evaluate binding properties of anti-CD33 monoclonal antibodies in preclinical cancer models.
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Affiliation(s)
- Kevin J. H. Allen
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | - Rubin Jiao
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | - Jason Li
- Actinium Pharmaceuticals, New York, NY 10016, USA
| | | | - Ekaterina Dadachova
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
- Correspondence: ; Tel.: +1-306-966-5163
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Damerow H, Cheng X, von Kiedrowski V, Schirrmacher R, Wängler B, Fricker G, Wängler C. Toward Optimized 89Zr-Immuno-PET: Side-by-Side Comparison of [ 89Zr]Zr-DFO-, [ 89Zr]Zr-3,4,3-(LI-1,2-HOPO)- and [ 89Zr]Zr-DFO*-Cetuximab for Tumor Imaging: Which Chelator Is the Most Suitable? Pharmaceutics 2022; 14:pharmaceutics14102114. [PMID: 36297549 PMCID: PMC9611803 DOI: 10.3390/pharmaceutics14102114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 09/26/2022] [Accepted: 09/29/2022] [Indexed: 11/21/2022] Open
Abstract
89Zr represents a highly favorable positron emitter for application in immuno-PET (Positron Emission Tomography) imaging. Clinically, the 89Zr4+ ion is introduced into antibodies by complexation with desferrioxamine B. However, producing complexes of limited kinetic inertness. Therefore, several new chelators for 89Zr introduction have been developed over the last years. Of these, the direct comparison of the most relevant ones for clinical translation, DFO* and 3,4,3-(LI-1,2-HOPO), is still missing. Thus, we directly compared DFO with DFO* and 3,4,3-(LI-1,2-HOPO) immunoconjugates to identify the most suitable agent stable 89Zr-complexation. The chelators were introduced into cetuximab, and an optical analysis method was developed, enabling the efficient quantification of derivatization sites per protein. The cetuximab conjugates were efficiently obtained and radiolabeled with 89Zr at 37 °C within 30 min, giving the [89Zr]Zr-cetuximab derivatives in high radiochemical yields and purities of >99% as well as specific activities of 50 MBq/mg. The immunoreactive fraction of all 89Zr-labeled cetuximab derivatives was determined to be in the range of 86.5−88.1%. In vivo PET imaging and ex vivo biodistribution studies in tumor-bearing animals revealed a comparable and significantly higher kinetic inertness for both [89Zr]Zr-3,4,3-(LI-1,2-HOPO)-cetuximab and [89Zr]Zr-DFO*-cetuximab, compared to [89Zr]Zr-DFO-cetuximab. Of these, [89Zr]Zr-DFO*-cetuximab showed a considerably more favorable pharmacokinetic profile with significantly lower liver and spleen retention than [89Zr]Zr-3,4,3-(LI-1,2-HOPO)-cetuximab. Since [89Zr]Zr-DFO* demonstrates a very high kinetic inertness, paired with a highly favorable pharmacokinetic profile of the resulting antibody conjugate, DFO* currently represents the most suitable chelator candidate for stable 89Zr-radiolabeling of antibodies and clinical translation.
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Affiliation(s)
- Helen Damerow
- Biomedical Chemistry, Clinic of Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany
| | - Xia Cheng
- Molecular Imaging and Radiochemistry, Clinic of Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany
| | - Valeska von Kiedrowski
- Molecular Imaging and Radiochemistry, Clinic of Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany
| | - Ralf Schirrmacher
- Division of Oncologic Imaging, Department of Oncology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 1Z2, Canada
| | - Björn Wängler
- Molecular Imaging and Radiochemistry, Clinic of Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany
| | - Gert Fricker
- Institute of Pharmacy and Molecular Biotechnology, University of Heidelberg, 69120 Heidelberg, Germany
| | - Carmen Wängler
- Biomedical Chemistry, Clinic of Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany
- Correspondence:
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Evaluation of different 89Zr-labeled synthons for direct labeling and tracking of white blood cells and stem cells in healthy athymic mice. Sci Rep 2022; 12:15646. [PMID: 36123386 PMCID: PMC9485227 DOI: 10.1038/s41598-022-19953-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 09/07/2022] [Indexed: 11/11/2022] Open
Abstract
Cell based therapies are evolving as an effective new approach to treat various diseases. To understand the safety, efficacy, and mechanism of action of cell-based therapies, it is imperative to follow their biodistribution noninvasively. Positron-emission-tomography (PET)-based non-invasive imaging of cell trafficking offers such a potential. Herein, we evaluated and compared three different ready-to-use direct cell radiolabeling synthons, [89Zr]Zr-DFO-Bn-NCS, [89Zr]Zr-Hy3ADA5-NCS, and [89Zr]Zr-Hy3ADA5-SA for PET imaging-based trafficking of white blood cells (WBCs) and stem cells (SCs) up to 7 days in athymic nude mice. We compared the degree of 89Zr complexation and percentage of cell radiolabeling efficiencies with each. All three synthons, [89Zr]Zr-DFO-Bn-NCS, [89Zr]Zr-Hy3ADA5-NCS, and [89Zr]Zr-Hy3ADA5-SA, were successfully prepared, and used for radiolabeling of WBCs and SCs. The highest cell radiolabeling yield was found for [89Zr]Zr-DFO-Bn-NCS, followed by [89Zr]Zr-Hy3ADA5-NCS, and [89Zr]Zr-Hy3ADA5-SA. In terms of biodistribution, WBCs radiolabeled with [89Zr]Zr-DFO-Bn-NCS or [89Zr]Zr-Hy3ADA5-NCS, were primarily accumulated in liver and spleen, whereas SCs radiolabeled with [89Zr]Zr-DFO-Bn-NCS or [89Zr]Zr-Hy3ADA5-NCS were found in lung, liver and spleen. A high bone uptake was observed for both WBCs and SCs radiolabeled with [89Zr]Zr-Hy3ADA5-SA, suggesting in-vivo instability of [89Zr]Zr-Hy3ADA5-SA synthon. This study offers an appropriate selection of ready-to-use radiolabeling synthons for noninvasive trafficking of WBCs, SCs and other cell-based therapies.
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Trastuzumab-conjugated oxine-based ligand for [ 89Zr]Zr 4+ immunoPET. J Inorg Biochem 2022; 235:111936. [PMID: 35878576 DOI: 10.1016/j.jinorgbio.2022.111936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 06/21/2022] [Accepted: 07/14/2022] [Indexed: 11/20/2022]
Abstract
A new, bifunctional chelating ligand for immuno-Positron Emission Tomography (PET) was designed, synthesized, and conjugated to Trastuzumab for a proof-of-concept study with 89Zr. H4neunox was synthesized from the tris(2-aminoethyl)amine backbone, decorated with 8-hydroxyquinoline moieties, and utilizes a primary amine for functionalization. A maleimide moiety extends the chelator to create H4neunox-mal for antibody conjugation via maleimide-thiol click chemistry. Preliminary 89Zr radiolabeling of H4neunox indicated quantitative radiolabeling at 1 × 10-5 M, but improved inertness towards human serum (96% intact at 7 d) and Fe3+ (92% intact at 24 h) compared to the previously synthesized H5decaox. The chelator was successfully conjugated to the monoclonal antibody, Trastuzumab, and used in preliminary radiolabeling reactions (37 °C, 2 h) with 89Zr. Radiochemical assessments of the new H4neunox-Trastuzumab conjugate include 89Zr radiolabeling, spin filter purification, cell-binding immunoreactivity, and in vivo PET imaging and biodistribution in SKOV-3 tumour bearing nude mice, performed in comparison with the desferrioxamine B analog, DFO-Trastuzumab. The [89Zr]Zr(neunox-Trastuzumab) showed lowered inertness towards serum (76% intact at 24 h) as well as demetallation in vivo through bone uptake (21% ID/g) in PET imaging and biodistribution studies when compared to [89Zr]Zr(DFO-Trastuzumab). Although the combination of the chelator and antibody had detrimental effects on their intended purposes, nonetheless, the primary amine platform of H4neunox developed here provides an oxine-based bifunctional ligand for further derivatizations with other targeting vectors.
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Fernandes EFA, Wilbs J, Raavé R, Jacobsen CB, Toftelund H, Helleberg H, Boswinkel M, Heskamp S, Gustafsson MBF, Bjørnsdottir I. Comparison of the Tissue Distribution of a Long-Circulating Glucagon-like Peptide-1 Agonist Determined by Positron Emission Tomography and Quantitative Whole-Body Autoradiography. ACS Pharmacol Transl Sci 2022; 5:616-624. [DOI: 10.1021/acsptsci.2c00075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
| | - Jonas Wilbs
- Global Research Technologies, Novo Nordisk A/S, Novo Nordisk Park 1, DK-2760 Måløv, Denmark
| | - Rene Raavé
- Radboudumc, Department of Medical Imaging − Nuclear Medicine, Radboud Institute for Molecular Life Sciences, 6500 HB Nijmegen, The Netherlands
| | - Christian Borch Jacobsen
- Isotope Chemistry, CMC Development, Novo Nordisk A/S, Novo Nordisk Park 1, DK-2760 Måløv, Denmark
| | - Hanne Toftelund
- Global Drug Discovery, Novo Nordisk A/S, Novo Nordisk Park 1, DK-2760 Måløv, Denmark
| | - Hans Helleberg
- Global Drug Discovery, Novo Nordisk A/S, Novo Nordisk Park 1, DK-2760 Måløv, Denmark
| | - Milou Boswinkel
- Radboudumc, Department of Medical Imaging − Nuclear Medicine, Radboud Institute for Molecular Life Sciences, 6500 HB Nijmegen, The Netherlands
| | - Sandra Heskamp
- Radboudumc, Department of Medical Imaging − Nuclear Medicine, Radboud Institute for Molecular Life Sciences, 6500 HB Nijmegen, The Netherlands
| | | | - Inga Bjørnsdottir
- Global Drug Discovery, Novo Nordisk A/S, Novo Nordisk Park 1, DK-2760 Måløv, Denmark
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Bauer D, Visca H, Weerakkody A, Carter LM, Samuels Z, Kaminsky S, Andreev OA, Reshetnyak YK, Lewis JS. PET Imaging of Acidic Tumor Environment With 89Zr-labeled pHLIP Probes. Front Oncol 2022; 12:882541. [PMID: 35664740 PMCID: PMC9160799 DOI: 10.3389/fonc.2022.882541] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/19/2022] [Indexed: 11/13/2022] Open
Abstract
Acidosis of the tumor microenvironment is a hallmark of tumor progression and has emerged as an essential biomarker for cancer diagnosis, prognosis, and evaluation of treatment response. A tool for quantitatively visualizing the acidic tumor environment could significantly advance our understanding of the behavior of aggressive tumors, improving patient management and outcomes. 89Zr-labeled pH-low insertion peptides (pHLIP) are a class of radiopharmaceutical imaging probes for the in vivo analysis of acidic tumor microenvironments via positron emission tomography (PET). Their unique structure allows them to sense and target acidic cancer cells. In contrast to traditional molecular imaging agents, pHLIP's mechanism of action is pH-dependent and does not rely on the presence of tumor-specific molecular markers. In this study, one promising acidity-imaging PET probe ([89Zr]Zr-DFO-Cys-Var3) was identified as a candidate for clinical translation.
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Affiliation(s)
- David Bauer
- Department of Radiology and the Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Hannah Visca
- Department of Physics, University of Rhode Island, Kingston, RI, United States
| | - Anuradha Weerakkody
- Department of Physics, University of Rhode Island, Kingston, RI, United States
| | - Lukas M. Carter
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Zachary Samuels
- Department of Radiology and the Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Spencer Kaminsky
- Department of Radiology and the Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Oleg A. Andreev
- Department of Physics, University of Rhode Island, Kingston, RI, United States
| | - Yana K. Reshetnyak
- Department of Physics, University of Rhode Island, Kingston, RI, United States
| | - Jason S. Lewis
- Department of Radiology and the Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY, United States
- Department of Radiology, Weill Cornell Medical College, New York, NY, United States
- Department of Pharmacology Program, Weill Cornell Medical College, New York, NY, United States
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Lauwerys L, Smits E, Van den Wyngaert T, Elvas F. Radionuclide Imaging of Cytotoxic Immune Cell Responses to Anti-Cancer Immunotherapy. Biomedicines 2022; 10:biomedicines10051074. [PMID: 35625811 PMCID: PMC9139020 DOI: 10.3390/biomedicines10051074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 04/24/2022] [Accepted: 04/30/2022] [Indexed: 11/16/2022] Open
Abstract
Cancer immunotherapy is an evolving and promising cancer treatment that takes advantage of the body’s immune system to yield effective tumor elimination. Importantly, immunotherapy has changed the treatment landscape for many cancers, resulting in remarkable tumor responses and improvements in patient survival. However, despite impressive tumor effects and extended patient survival, only a small proportion of patients respond, and others can develop immune-related adverse events associated with these therapies, which are associated with considerable costs. Therefore, strategies to increase the proportion of patients gaining a benefit from these treatments and/or increasing the durability of immune-mediated tumor response are still urgently needed. Currently, measurement of blood or tissue biomarkers has demonstrated sampling limitations, due to intrinsic tumor heterogeneity and the latter being invasive. In addition, the unique response patterns of these therapies are not adequately captured by conventional imaging modalities. Consequently, non-invasive, sensitive, and quantitative molecular imaging techniques, such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT) using specific radiotracers, have been increasingly used for longitudinal whole-body monitoring of immune responses. Immunotherapies rely on the effector function of CD8+ T cells and natural killer cells (NK) at tumor lesions; therefore, the monitoring of these cytotoxic immune cells is of value for therapy response assessment. Different immune cell targets have been investigated as surrogate markers of response to immunotherapy, which motivated the development of multiple imaging agents. In this review, the targets and radiotracers being investigated for monitoring the functional status of immune effector cells are summarized, and their use for imaging of immune-related responses are reviewed along their limitations and pitfalls, of which multiple have already been translated to the clinic. Finally, emerging effector immune cell imaging strategies and future directions are provided.
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Affiliation(s)
- Louis Lauwerys
- Molecular Imaging Center Antwerp (MICA), Integrated Personalized and Precision Oncology Network (IPPON), Faculty of Medicine and Health Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium; (L.L.); (T.V.d.W.)
| | - Evelien Smits
- Center for Oncological Research (CORE), Integrated Personalized and Precision Oncology Network (IPPON), Faculty of Medicine and Health Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium;
- Center for Cell Therapy and Regenerative Medicine, Antwerp University Hospital, Drie Eikenstraat 655, B-2650 Edegem, Belgium
| | - Tim Van den Wyngaert
- Molecular Imaging Center Antwerp (MICA), Integrated Personalized and Precision Oncology Network (IPPON), Faculty of Medicine and Health Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium; (L.L.); (T.V.d.W.)
- Nuclear Medicine, Antwerp University Hospital, Drie Eikenstraat 655, B-2650 Edegem, Belgium
| | - Filipe Elvas
- Molecular Imaging Center Antwerp (MICA), Integrated Personalized and Precision Oncology Network (IPPON), Faculty of Medicine and Health Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium; (L.L.); (T.V.d.W.)
- Correspondence:
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Sharma SK, Suzuki M, Xu H, Korsen JA, Samuels Z, Guo H, Nemieboka B, Piersigilli A, Edwards KJ, Cheung NKV, Lewis JS. Influence of Fc Modifications and IgG Subclass on Biodistribution of Humanized Antibodies Targeting L1CAM. J Nucl Med 2022; 63:629-636. [PMID: 34353869 PMCID: PMC8973293 DOI: 10.2967/jnumed.121.262383] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 07/15/2021] [Indexed: 11/16/2022] Open
Abstract
Immuno-PET is a powerful tool to noninvasively characterize the in vivo biodistribution of engineered antibodies. Methods: L1 cell adhesion molecule-targeting humanized (HuE71) IgG1 and IgG4 antibodies bearing identical variable heavy- and light-chain sequences but different fragment crystallizable (Fc) portions were radiolabeled with 89Zr, and the in vivo biodistribution was studied in SKOV3 ovarian cancer xenografted nude mice. Results: In addition to showing uptake in L1 cell adhesion molecule-expressing SKOV3 tumors, as does its parental counterpart HuE71 IgG1, the afucosylated variant having enhanced Fc-receptor affinity showed high nonspecific uptake in lymph nodes. On the other hand, aglycosylated HuE71 IgG1 with abrogated Fc-receptor binding did not show lymphoid uptake. The use of the IgG4 subclass showed high nonspecific uptake in the kidneys, which was prevented by mutating serine at position 228 to proline in the hinge region of the IgG4 antibody to mitigate in vivo fragment antigen-binding arm exchange. Conclusion: Our findings highlight the influence of Fc modifications and the choice of IgG subclass on the in vivo biodistribution of antibodies and the potential outcomes thereof.
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Affiliation(s)
- Sai Kiran Sharma
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Maya Suzuki
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York
- Center for Clinical and Translational Research, Kyushu University Hospital, Fukuoka, Japan
| | - Hong Xu
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Joshua A Korsen
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Pharmacology, Weill Cornell Medical College, New York, New York
| | - Zachary Samuels
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Hongfen Guo
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Brandon Nemieboka
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
- Gerstner Sloan Kettering Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Alessandra Piersigilli
- Tri-Institutional Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, Weill Cornell Medical College, and Rockefeller University, New York, New York
| | - Kimberly J Edwards
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Nai-Kong V Cheung
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York;
- Department of Pharmacology, Weill Cornell Medical College, New York, New York
- Gerstner Sloan Kettering Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Jason S Lewis
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York;
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
- Gerstner Sloan Kettering Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Radiology, Weill Cornell Medical College, New York, New York; and
- Radiochemistry and Molecular Imaging Probes Core, Memorial Sloan Kettering Cancer Center, New York, New York
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Immuno-PET Imaging of Atherosclerotic Plaques with [89Zr]Zr-Anti-CD40 mAb—Proof of Concept. BIOLOGY 2022; 11:biology11030408. [PMID: 35336782 PMCID: PMC8944956 DOI: 10.3390/biology11030408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 02/28/2022] [Accepted: 03/03/2022] [Indexed: 11/16/2022]
Abstract
Non-invasive imaging of atherosclerosis can help in the identification of vulnerable plaque lesions. CD40 is a co-stimulatory molecule present on various immune and non-immune cells in the plaques and is linked to inflammation and plaque instability. We hypothesize that a 89Zr-labeled anti-CD40 monoclonal antibody (mAb) tracer has the potential to bind to cells present in atherosclerotic lesions and that CD40 Positron Emission Tomography (PET) can contribute to the detection of vulnerable atherosclerotic plaque lesions. To study this, wild-type (WT) and ApoE−/− mice were fed a high cholesterol diet for 14 weeks to develop atherosclerosis. Mice were injected with [89Zr]Zr-anti-CD40 mAb and the aortic uptake was evaluated and quantified using PET/Computed Tomography (CT) imaging. Ex vivo biodistribution was performed post-PET imaging and the uptake in the aorta was assessed with autoradiography and compared with Oil red O staining to determine the tracer potential to detect atherosclerotic plaques. On day 3 and 7 post injection, analysis of [89Zr]Zr-anti-CD40 mAb PET/CT scans showed a more pronounced aortic signal in ApoE−/− compared to WT mice with an increased aorta-to-blood uptake ratio. Autoradiography revealed [89Zr]Zr-anti-CD40 mAb uptake in atherosclerotic plaque areas in ApoE−/− mice, while no signal was found in WT mice. Clear overlap was observed between plaque areas as identified by Oil red O staining and autoradiography signal of [89Zr]Zr-anti-CD40 mAb in ApoE−/− mice. In this proof of concept study, we showed that PET/CT with [89Zr]Zr-anti-CD40 mAb can detect atherosclerotic plaques. As CD40 is associated with plaque vulnerability, [89Zr]Zr-anti-CD40 mAb has the potential to become a tracer to detect vulnerable atherosclerotic plaques.
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Chen J, Wang J, Xu M, Jia X, Song G, Liu Z. Production of positron-emitting radionuclide yttrium-86 with a computer-aided design target for positron emission tomography. Nucl Med Biol 2022; 108-109:54-60. [DOI: 10.1016/j.nucmedbio.2022.03.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 02/18/2022] [Accepted: 03/08/2022] [Indexed: 01/21/2023]
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Gosmann D, Russelli L, Weber WA, Schwaiger M, Krackhardt AM, D'Alessandria C. Promise and challenges of clinical non-invasive T-cell tracking in the era of cancer immunotherapy. EJNMMI Res 2022; 12:5. [PMID: 35099641 PMCID: PMC8804060 DOI: 10.1186/s13550-022-00877-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 01/05/2022] [Indexed: 12/12/2022] Open
Abstract
In the last decades, our understanding of the role of the immune system in cancer has significantly improved and led to the discovery of new immunotherapeutic targets and tools, which boosted the advances in cancer immunotherapy to fight a growing number of malignancies. Approved immunotherapeutic approaches are currently mainly based on immune checkpoint inhibitors, antibody-derived targeted therapies, or cell-based immunotherapies. In essence, these therapies induce or enhance the infiltration and function of tumor-reactive T cells within the tumors, ideally resulting in complete tumor eradication. While the clinical application of immunotherapies has shown great promise, these therapies are often accompanied either by a variety of side effects as well as partial or complete unresponsiveness of a number of patients. Since different stages of disease progression elicit different local and systemic immune responses, the ability to longitudinally interrogate the migration and expansion of immune cells, especially T cells, throughout the whole body might greatly facilitate disease characterization and understanding. Furthermore, it can serve as a tool to guide development as well as selection of appropriate treatment regiments. This review provides an overview about a variety of immune-imaging tools available to characterize and study T-cell responses induced by anti-cancer immunotherapy. Moreover, challenges are discussed that must be taken into account and overcome to use immune-imaging tools as predictive and surrogate markers to enhance assessment and successful application of immunotherapies.
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Affiliation(s)
- Dario Gosmann
- Klinik und Poliklinik für Innere Medizin III, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Lisa Russelli
- Klinik und Poliklinik für Nuklearmedizin, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Wolfgang A Weber
- Klinik und Poliklinik für Nuklearmedizin, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Markus Schwaiger
- Klinik und Poliklinik für Nuklearmedizin, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Angela M Krackhardt
- Klinik und Poliklinik für Innere Medizin III, Klinikum rechts der Isar, Technische Universität München, Munich, Germany. .,German Cancer Consortium (DKTK), Partner-Site Munich and German Cancer Research Center (DKFZ), Heidelberg, Germany.
| | - Calogero D'Alessandria
- Klinik und Poliklinik für Nuklearmedizin, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.
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Damerow H, Hübner R, Judmann B, Schirrmacher R, Wängler B, Fricker G, Wängler C. Side-by-Side Comparison of Five Chelators for 89Zr-Labeling of Biomolecules: Investigation of Chemical/Radiochemical Properties and Complex Stability. Cancers (Basel) 2021; 13:cancers13246349. [PMID: 34944969 PMCID: PMC8699488 DOI: 10.3390/cancers13246349] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 12/01/2021] [Accepted: 12/14/2021] [Indexed: 12/22/2022] Open
Abstract
In this work, five different chelating agents, namely DFO, CTH-36, DFO*, 3,4,3-(LI-1,2-HOPO) and DOTA-GA, were compared with regard to the relative kinetic inertness of their corresponding 89Zr complexes to evaluate their potential for in vivo application and stable 89Zr complexation. The chelators were identically functionalized with tetrazines, enabling a fully comparable, efficient, chemoselective and biorthogonal conjugation chemistry for the modification of any complementarily derivatized biomolecules of interest. A small model peptide of clinical relevance (TCO-c(RGDfK)) was derivatized via iEDDA click reaction with the developed chelating agents (TCO = trans-cyclooctene and iEDDA = inverse electron demand Diels-Alder). The bioconjugates were labeled with 89Zr4+, and their radiochemical properties (labeling conditions and efficiency), logD(7.4), as well as the relative kinetic inertness of the formed complexes, were compared. Furthermore, density functional theory (DFT) calculations were conducted to identify potential influences of chelator modification on complex formation and geometry. The results of the DFT studies showed-apart from the DOTA-GA derivative-no significant influence of chelator backbone functionalization or the conjugation of the chelator tetrazines by iEDDA. All tetrazines could be efficiently introduced into c(RGDfK), demonstrating the high suitability of the agents for efficient and chemoselective bioconjugation. The DFO-, CTH-36- and DFO*-modified c(RGDfK) peptides showed a high radiolabeling efficiency under mild reaction conditions and complete 89Zr incorporation within 1 h, yielding the 89Zr-labeled analogs as homogenous products. In contrast, 3,4,3-(LI-1,2-HOPO)-c(RGDfK) required considerably prolonged reaction times of 5 h for complete radiometal incorporation and yielded several different 89Zr-labeled species. The labeling of the DOTA-GA-modified peptide was not successful at all. Compared to [89Zr]Zr-DFO-, [89Zr]Zr-CTH-36- and [89Zr]Zr-DFO*-c(RGDfK), the corresponding [89Zr]Zr-3,4,3-(LI-1,2-HOPO) peptide showed a strongly increased lipophilicity. Finally, the relative stability of the 89Zr complexes against the EDTA challenge was investigated. The [89Zr]Zr-DFO complex showed-as expected-a low kinetic inertness. Unexpectedly, also, the [89Zr]Zr-CTH-36 complex demonstrated a high susceptibility against the challenge, limiting the usefulness of CTH-36 for stable 89Zr complexation. Only the [89Zr]Zr-DFO* and the [89Zr]Zr-3,4,3-(LI-1,2-HOPO) complexes demonstrated a high inertness, qualifying them for further comparative in vivo investigation to determine the most appropriate alternative to DFO for clinical application.
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Affiliation(s)
- Helen Damerow
- Biomedical Chemistry, Clinic of Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany; (H.D.); (R.H.); (B.J.)
| | - Ralph Hübner
- Biomedical Chemistry, Clinic of Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany; (H.D.); (R.H.); (B.J.)
| | - Benedikt Judmann
- Biomedical Chemistry, Clinic of Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany; (H.D.); (R.H.); (B.J.)
- Molecular Imaging and Radiochemistry, Clinic of Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany;
| | - Ralf Schirrmacher
- Department of Oncology, Division of Oncological Imaging, University of Alberta, 11560 University Avenue, Edmonton, AB T6G 1Z2, Canada;
| | - Björn Wängler
- Molecular Imaging and Radiochemistry, Clinic of Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany;
| | - Gert Fricker
- Institute of Pharmacy and Molecular Biotechnology, University of Heidelberg, Im Neuenheimer Feld 329, 69120 Heidelberg, Germany;
| | - Carmen Wängler
- Biomedical Chemistry, Clinic of Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany; (H.D.); (R.H.); (B.J.)
- Correspondence: ; Tel.: +49-621-383-3761
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Klasen B, Lemcke D, Mindt TL, Gasser G, Rösch F. Development and in vitro evaluation of new bifunctional 89Zr-chelators based on the 6-amino-1,4-diazepane scaffold for immuno-PET applications. Nucl Med Biol 2021; 102-103:12-23. [PMID: 34242949 DOI: 10.1016/j.nucmedbio.2021.06.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 06/15/2021] [Accepted: 06/25/2021] [Indexed: 10/21/2022]
Abstract
INTRODUCTION Combination of hydroxamate bearing side chains with the 6-amino-1,4-diazepane scaffold provides a promising strategy for fast and stable 89Zr-labeling of antibodies. Following this approach, we hereby present the development, labeling kinetics and in vitro complex stability of three resulting bifunctional chelator derivatives both stand-alone and coupled to a model protein in comparison to different linear deferoxamine (DFO) derivatives. METHODS The novel 89Zr-chelator Hy3ADA5 was prepared via amide-coupling of separately synthesized 6-amino-1,4-diazepane-6-pentanoic acid and hydroxamate-containing side chains. Two further bifunctional derivatives were synthesized by extending the resulting system with either a squaramide- or p-isothiocyanatophenyl moiety for simplified binding to proteins. After coupling to a model antibody and purification, the resulting immunoconjugates as well as the unbound chelator derivatives were 89Zr-labeled at room temperature (RT) and neutral pH. For comparison, different DFO derivatives were analogously coupled, purified and radiolabeled. In vitro complex stability of the resulting radioconjugates was investigated in phosphate buffered saline (PBS) and human serum at 37 °C over a period of 7 days. RESULTS 89Zr-labeling of the novel unbound Hy3ADA5 derivatives indicated rapid complexation kinetics resulting in high radiochemical conversions (RCC) of 84-94% after 90 min. Similar or even faster radiolabeling with slightly increased maximum yields was obtained using the DFO-analogues. Initially, [89Zr]Zr-DFO*-p-Ph-NCS showed a delayed formation, nevertheless reaching almost quantitative complexation. Radiolabeling of the corresponding immunoconjugates Hy3ADA5-SA-mAb and Hy3ADA5-p-Ph-NCS-mAb resulted in 82.0 ± 1.1 and 89.2 ± 0.7% RCC, respectively after 90 min representing high but slightly lower labeling efficiency compared to the DFO- and DFO*-functionalized analogues. All examined radioimmunoconjugates showed very high in vitro complex stability both in human serum and PBS, providing no significant release of the radiometal. In the case of unbound chelators, however, the p-Ph-NCS-functionalized derivatives indicated considerable instability in human serum already after 1 h. CONCLUSION The novel chelator derivatives based on hydroxamate-functionalized 6-amino-1,4-diazepane revealed fast and high yielding 89Zr-labeling kinetics as well as high in vitro complex stability both stand-alone and coupled to an antibody. Therefore, Hy3ADA5 represents a promising tool for radiolabeling of biomolecules such as antibodies at mild conditions for immuno-PET applications.
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Affiliation(s)
- Benedikt Klasen
- Department of Chemistry - TRIGA site, Johannes Gutenberg University Mainz, Germany.
| | - Daniel Lemcke
- Department of Chemistry - TRIGA site, Johannes Gutenberg University Mainz, Germany
| | - Thomas L Mindt
- Ludwig Boltzmann Institute Applied Diagnostics, General Hospital Vienna, Austria; Department of Inorganic Chemistry, Faculty of Chemistry, University of Vienna, Austria
| | - Gilles Gasser
- Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, Laboratory for Inorganic Chemical Biology, Paris, France
| | - Frank Rösch
- Department of Chemistry - TRIGA site, Johannes Gutenberg University Mainz, Germany.
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A Semi Rigid Novel Hydroxamate AMPED-Based Ligand for 89Zr PET Imaging. Molecules 2021; 26:molecules26195819. [PMID: 34641362 PMCID: PMC8512011 DOI: 10.3390/molecules26195819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/16/2021] [Accepted: 09/20/2021] [Indexed: 11/23/2022] Open
Abstract
In this work, we designed, developed, characterized, and investigated a new chelator and its bifunctional derivative for 89Zr labeling and PET-imaging. In a preliminary study, we synthesized two hexadentate chelators named AAZTHAS and AAZTHAG, based on the seven-membered heterocycle AMPED (6-amino-6-methylperhydro-1,4-diazepine) with the aim to increase the rigidity of the 89Zr complex by using N-methyl-N-(hydroxy)succinamide or N-methyl-N-(hydroxy)glutaramide pendant arms attached to the cyclic structure. N-methylhydroxamate groups are the donor groups chosen to efficiently coordinate 89Zr. After in vitro stability tests, we selected the chelator with longer arms, AAZTHAG, as the best complexing agent for 89Zr presenting a stability of 86.4 ± 5.5% in human serum (HS) for at least 72 h. Small animal PET/CT static scans acquired at different time points (up to 24 h) and ex vivo organ distribution studies were then carried out in healthy nude mice (n = 3) to investigate the stability and biodistribution in vivo of this new 89Zr-based complex. High stability in vivo, with low accumulation of free 89Zr in bones and kidneys, was measured. Furthermore, an activated ester functionalized version of AAZTHAG was synthesized to allow the conjugation with biomolecules such as antibodies. The bifunctional chelator was then conjugated to the human anti-HER2 monoclonal antibody Trastuzumab (Tz) as a proof of principle test of conjugation to biologically active molecules. The final 89Zr labeled compound was characterized via radio-HPLC and SDS-PAGE followed by autoradiography, and its stability in different solutions was assessed for at least 4 days.
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The Race for Hydroxamate-Based Zirconium-89 Chelators. Cancers (Basel) 2021; 13:cancers13174466. [PMID: 34503276 PMCID: PMC8431476 DOI: 10.3390/cancers13174466] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 08/30/2021] [Accepted: 08/31/2021] [Indexed: 12/18/2022] Open
Abstract
Simple Summary Chelators are small molecules that can form a complex with a metal ion by coordinating electron rich atoms from the chelator to the electron-poor cation. Bifunctionalization of the chelator allows for the coupling of the chelator to a vector, such as a biomolecule. Using this approach, radiolabeling of biomolecules with metallic radionuclides can be performed, enabling nuclear imaging studies for diagnosis and radiotherapy of diseases. In the case of positron emission tomography (PET) of radiolabeled antibodies, this approach is called immunoPET. In this review we focus on chelators using hydroxamate groups to coordinate the radionuclide zirconium-89 ([89Zr]Zr4+, denoted as 89Zr in the following). The most common chelator used in this context is desferrioxamine (DFO). However, preclinical studies indicate that the 89Zr-DFO complex is not stable enough in vivo, in particular when combined with biomolecules with slow pharmacokinetics (e.g., antibodies). Subsequently, new chelators with improved properties have been developed, of which some show promising potential. The progress is summarized in this review. Abstract Metallic radionuclides conjugated to biological vectors via an appropriate chelator are employed in nuclear medicine for the diagnosis (imaging) and radiotherapy of diseases. For the application of radiolabeled antibodies using positron emission tomography (immunoPET), zirconium-89 has gained increasing interest over the last decades as its physical properties (t1/2 = 78.4 h, 22.6% β+ decay) match well with the slow pharmacokinetics of antibodies (tbiol. = days to weeks) allowing for late time point imaging. The most commonly used chelator for 89Zr in this context is desferrioxamine (DFO). However, it has been shown in preclinical studies that the hexadentate DFO ligand does not provide 89Zr-complexes of sufficient stability in vivo and unspecific uptake of the osteophilic radiometal in bones is observed. For clinical applications, this might be of concern not only because of an unnecessary dose to the patient but also an increased background signal. As a consequence, next generation chelators based on hydroxamate scaffolds for more stable coordination of 89Zr have been developed by different research groups. In this review, we describe the progress in this research field until end of 2020, including promising examples of new candidates of chelators currently in advanced stages for clinical translation that outrun the performance of the current gold standard DFO.
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Grus T, Lahnif H, Klasen B, Moon ES, Greifenstein L, Roesch F. Squaric Acid-Based Radiopharmaceuticals for Tumor Imaging and Therapy. Bioconjug Chem 2021; 32:1223-1231. [PMID: 34170116 DOI: 10.1021/acs.bioconjchem.1c00305] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Targeting vectors bound to a chelator represent a significant fraction of radiopharmaceuticals used nowadays for diagnostic and therapeutic purposes in nuclear medicine. The use of squaramides as coupling units for chelator and targeting vector helps to circumvent the disadvantages of several common coupling methods. This review gives an overview of the use of squaric acid diesters (SADE) as linking agents. It focuses on the conjugation of cyclic chelators, e.g., DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid), as well as hybrid chelators like AAZTA5 (6-pentanoic acid-6-amino-1,4-diazepine tetracetic acid) or DATA5m (6-pentanoic acid-6-amino-1,4-diazapine-triacetate) to different targeting vectors, e.g., prostate-specific membrane antigen inhibitors (KuE; PSMAi), fibroblast activation protein inhibitors (FAPi), and monoclonal antibodies (mAbs). An overview of the synthesis, radiolabeling, and in vitro and in vivo behavior of the described structures is given. The unique properties of SADE enable a fast and simple conjugation of chelators to biomolecules, peptides, and small molecules under mild conditions. Furthermore, SA-containing conjugates could not only display similar in vitro characteristics in terms of binding affinity when compared to reference compounds, but may even induce beneficial effects on the pharmacokinetic properties of these radiopharmaceuticals.
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Affiliation(s)
- Tilmann Grus
- Department of Chemistry - TRIGA site, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
| | - Hanane Lahnif
- Department of Chemistry - TRIGA site, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
| | - Benedikt Klasen
- Department of Chemistry - TRIGA site, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
| | - Euy-Sung Moon
- Department of Chemistry - TRIGA site, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
| | - Lukas Greifenstein
- Department of Chemistry - TRIGA site, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
| | - Frank Roesch
- Department of Chemistry - TRIGA site, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
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47
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Guillou A, Earley DF, Klingler S, Nisli E, Nüesch LJ, Fay R, Holland JP. The Influence of a Polyethylene Glycol Linker on the Metabolism and Pharmacokinetics of a 89Zr-Radiolabeled Antibody. Bioconjug Chem 2021; 32:1263-1275. [PMID: 34056896 DOI: 10.1021/acs.bioconjchem.1c00172] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Most experimental work in the space of bioconjugation chemistry focuses on using new methods to construct covalent bonds between a cargo molecule and a protein of interest such as a monoclonal antibody (mAb). Bond formation is important for generating new diagnostic tools, yet when these compounds advance to preclinical in vitro and in vivo studies, and later for translation to the clinic, understanding the fate of potential metabolites that arise from chemical or enzymatic degradation of the construct is important to obtain a full picture of the pharmacokinetic performance of a new compound. In the context of designing new bioconjugate methods for labeling antibodies with the positron-emitting radionuclide 89Zr, we previously developed a photochemical process for making 89Zr-mAbs. Experimental studies on [89Zr]ZrDFO-PEG3-azepin-mAb constructs revealed that incorporation of the tris-polyethylene glycol (PEG3) linker improved the aqueous phase solubility and radiochemical conversion. However, the use of a PEG3 linker also has an impact on the whole-body residence time of the construct, leading to a more rapid excretion of the 89Zr activity when compared with radiotracers that lack the PEG3 chain. In this work, we investigated the metabolic fate of eight possible metabolites that arise from the logical disconnection of [89Zr]ZrDFO-PEG3-azepin-mAb at bonds which are susceptible to chemical or enzymatic cleavage. Synthesis combined with 89Zr-radiolabeling, small-animal positron emission tomography imaging at multiple time points from 0 to 20 h, and measurements of the effective half-life for whole-body excretion are reported. The conclusions are that the use of a PEG3 linker is non-innocent in terms of its impact on enhancing the metabolism of [89Zr]ZrDFO-PEG3-azepin-mAbs. In most cases, degradation can produce metabolites that are rapidly eliminated from the body, thereby enhancing image contrast by reducing nonspecific accumulation and retention of 89Zr in background organs such as the liver, spleen, kidney, and bone.
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Affiliation(s)
- Amaury Guillou
- Department of Chemistry University of Zurich Winterthurerstrasse 190 CH-8057, Zurich, Switzerland
| | - Daniel F Earley
- Department of Chemistry University of Zurich Winterthurerstrasse 190 CH-8057, Zurich, Switzerland
| | - Simon Klingler
- Department of Chemistry University of Zurich Winterthurerstrasse 190 CH-8057, Zurich, Switzerland
| | - Eda Nisli
- Department of Chemistry University of Zurich Winterthurerstrasse 190 CH-8057, Zurich, Switzerland
| | - Laura J Nüesch
- Department of Chemistry University of Zurich Winterthurerstrasse 190 CH-8057, Zurich, Switzerland
| | - Rachael Fay
- Department of Chemistry University of Zurich Winterthurerstrasse 190 CH-8057, Zurich, Switzerland
| | - Jason P Holland
- Department of Chemistry University of Zurich Winterthurerstrasse 190 CH-8057, Zurich, Switzerland
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48
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Chomet M, van Dongen GAMS, Vugts DJ. State of the Art in Radiolabeling of Antibodies with Common and Uncommon Radiometals for Preclinical and Clinical Immuno-PET. Bioconjug Chem 2021; 32:1315-1330. [PMID: 33974403 PMCID: PMC8299458 DOI: 10.1021/acs.bioconjchem.1c00136] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
![]()
Inert
and stable radiolabeling of monoclonal antibodies (mAb),
antibody fragments, or antibody mimetics with radiometals is a prerequisite
for immuno-PET. While radiolabeling is preferably fast, mild, efficient,
and reproducible, especially when applied for human use in a current
Good Manufacturing Practice compliant way, it is crucial that the
obtained radioimmunoconjugate is stable and shows preserved immunoreactivity
and in vivo behavior. Radiometals and chelators have
extensively been evaluated to come to the most ideal radiometal–chelator
pair for each type of antibody derivative. Although PET imaging of
antibodies is a relatively recent tool, applications with 89Zr, 64Cu, and 68Ga have greatly increased in
recent years, especially in the clinical setting, while other less
common radionuclides such as 52Mn, 86Y, 66Ga, and 44Sc, but also 18F as in [18F]AlF are emerging promising candidates for the radiolabeling
of antibodies. This review presents a state of the art overview of
the practical aspects of radiolabeling of antibodies, ranging from
fast kinetic affibodies and nanobodies to slow kinetic intact mAbs.
Herein, we focus on the most common approach which consists of first
modification of the antibody with a chelator, and after eventual storage
of the premodified molecule, radiolabeling as a second step. Other
approaches are possible but have been excluded from this review. The
review includes recent and representative examples from the literature
highlighting which radiometal–chelator–antibody combinations
are the most successful for in vivo application.
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Affiliation(s)
- Marion Chomet
- Amsterdam UMC, Vrije Universiteit Amsterdam, Radiology & Nuclear Medicine, Cancer Center Amsterdam, De Boelelaan 1117, Amsterdam 1081 HV, The Netherlands
| | - Guus A M S van Dongen
- Amsterdam UMC, Vrije Universiteit Amsterdam, Radiology & Nuclear Medicine, Cancer Center Amsterdam, De Boelelaan 1117, Amsterdam 1081 HV, The Netherlands
| | - Danielle J Vugts
- Amsterdam UMC, Vrije Universiteit Amsterdam, Radiology & Nuclear Medicine, Cancer Center Amsterdam, De Boelelaan 1117, Amsterdam 1081 HV, The Netherlands
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49
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Sharma SK, Adumeau P, Keinänen O, Sisodiya V, Sarvaiya H, Tchelepi R, Korsen JA, Pourat J, Edwards KJ, Ragupathi A, Hamdy O, Saunders LR, Rudin CM, Poirier JT, Lewis JS, Zeglis BM. Synthesis and Comparative In Vivo Evaluation of Site-Specifically Labeled Radioimmunoconjugates for DLL3-Targeted ImmunoPET. Bioconjug Chem 2021; 32:1255-1262. [PMID: 33835770 PMCID: PMC8295218 DOI: 10.1021/acs.bioconjchem.1c00121] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Delta-like ligand 3 (DLL3) is a therapeutic target for the treatment of small cell lung cancer, neuroendocrine prostate cancer, and isocitrate dehydrogenase mutant glioma. In the clinic, DLL3-targeted 89Zr-immunoPET has the potential to aid in the assessment of disease burden and facilitate the selection of patients suitable for therapies that target the antigen. The overwhelming majority of 89Zr-labeled radioimmunoconjugates are synthesized via the random conjugation of desferrioxamine (DFO) to lysine residues within the immunoglobulin. While this approach is admittedly facile, it can produce heterogeneous constructs with suboptimal in vitro and in vivo behavior. In an effort to circumvent these issues, we report the development and preclinical evaluation of site-specifically labeled radioimmunoconjugates for DLL3-targeted immunoPET. To this end, we modified a cysteine-engineered variant of the DLL3-targeting antibody SC16-MB1 with two thiol-reactive variants of DFO: one bearing a maleimide moiety (Mal-DFO) and the other containing a phenyloxadiazolyl methyl sulfone group (PODS-DFO). In an effort to obtain immunoconjugates with a DFO-to-antibody ratio (DAR) of 2, we explored both the reduction of the antibody with tris(2-carboxyethyl) phosphine (TCEP) as well as the use of a combination of glutathione and arginine as reducing and stabilizing agents, respectively. While exerting control over the DAR of the immunoconjugate proved cumbersome using TCEP, the use of glutathione and arginine enabled the selective reduction of the engineered cysteines and thus the formation of homogeneous immunoconjugates. A head-to-head comparison of the resulting 89Zr-radioimmunoconjugates in mice bearing DLL3-expressing H82 xenografts revealed no significant differences in tumoral uptake and showed comparable radioactivity concentrations in most healthy nontarget organs. However, 89Zr-DFOPODS-DAR2SC16-MB1 produced 30% lower uptake (3.3 ± 0.5 %ID/g) in the kidneys compared to 89Zr-DFOMal-DAR2SC16-MB1 (4.7 ± 0.5 %ID/g). In addition, H82-bearing mice injected with a 89Zr-labeled isotype-control radioimmunoconjugate synthesized using PODS exhibited ∼40% lower radioactivity in the kidneys compared to mice administered its maleimide-based counterpart. Taken together, these results demonstrate the improved in vivo performance of the PODS-based radioimmunoconjugate and suggest that a stable, well-defined DAR2 radiopharmaceutical may be suitable for the clinical immunoPET of DLL3-expressing cancers.
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Affiliation(s)
- Sai Kiran Sharma
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Department of Chemistry, Hunter College, City University of New York, New York, New York 10021, United States
| | - Pierre Adumeau
- Department of Chemistry, Hunter College, City University of New York, New York, New York 10021, United States
| | - Outi Keinänen
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Department of Chemistry, Hunter College, City University of New York, New York, New York 10021, United States
| | - Vikram Sisodiya
- Abbvie Stemcentrx, South San Francisco, California 94080, United States
| | - Hetal Sarvaiya
- Abbvie Stemcentrx, South San Francisco, California 94080, United States
| | - Robert Tchelepi
- Abbvie Stemcentrx, South San Francisco, California 94080, United States
| | - Joshua A Korsen
- Department of Pharmacology, Weill Cornell Medical College, New York, New York 10021, United States
| | - Jacob Pourat
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Kimberly J Edwards
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Ashwin Ragupathi
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Omar Hamdy
- Abbvie Stemcentrx, South San Francisco, California 94080, United States
| | - Laura R Saunders
- Abbvie Stemcentrx, South San Francisco, California 94080, United States
| | - Charles M Rudin
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - John T Poirier
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Jason S Lewis
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Department of Pharmacology, Weill Cornell Medical College, New York, New York 10021, United States.,Department of Radiology, Weill Cornell Medical College, New York, New York 10021, United States.,Radiochemistry and Molecular Imaging Probes Core, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Brian M Zeglis
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Department of Chemistry, Hunter College, City University of New York, New York, New York 10021, United States.,Department of Radiology, Weill Cornell Medical College, New York, New York 10021, United States
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50
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Burvenich IJG, Goh YW, Guo N, Gan HK, Rigopoulos A, Cao D, Liu Z, Ackermann U, Wichmann CW, McDonald AF, Huynh N, O'Keefe GJ, Gong SJ, Scott FE, Li L, Geng W, Zutshi A, Lan Y, Scott AM. Radiolabelling and preclinical characterization of 89Zr-Df-radiolabelled bispecific anti-PD-L1/TGF-βRII fusion protein bintrafusp alfa. Eur J Nucl Med Mol Imaging 2021; 48:3075-3088. [PMID: 33608805 DOI: 10.1007/s00259-021-05251-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 02/08/2021] [Indexed: 12/01/2022]
Abstract
PURPOSE Τhis study aimed to optimize the 89Zr-radiolabelling of bintrafusp alfa investigational drug product and controls, and perform the in vitro and in vivo characterization of 89Zr-Df-bintrafusp alfa and 89Zr-Df-control radioconjugates. METHODS Bintrafusp alfa (anti-PD-L1 human IgG1 antibody fused to TGF-β receptor II (TGF-βRII), avelumab (anti-PD-L1 human IgG1 control antibody), isotype control (mutated inactive anti-PD-L1 IgG1 control antibody), and trap control (mutated inactive anti-PD-L1 human IgG1 fused to active TGF-βRII) were chelated with p-isothiocyanatobenzyl-desferrioxamine (Df). After radiolabelling with zirconium-89 (89Zr), radioconjugates were assessed for radiochemical purity, immunoreactivity, antigen binding affinity, and serum stability in vitro. In vivo biodistribution and imaging studies were performed with PET/CT to identify and quantitate 89Zr-Df-bintrafusp alfa tumour uptake in a PD-L1/TGF-β-positive murine breast cancer model (EMT-6). Specificity of 89Zr-Df-bintrafusp alfa was assessed via a combined biodistribution and imaging experiment in the presence of competing cold bintrafusp alfa (1 mg/kg). RESULTS Nanomolar affinities for PD-L1 were achieved with 89Zr-Df-bintrafusp alfa and 89Zr-avelumab. Biodistribution and imaging studies in PD-L1- and TGF-β-positive EMT-6 tumour-bearing BALB/c mice demonstrated the biologic similarity of 89Zr-Df-bintrafusp alfa and 89Zr-avelumab indicating the in vivo distribution pattern of bintrafusp alfa is driven by its PD-L1 binding arm. Competition study with 1 mg of unlabelled bintrafusp alfa or avelumab co-administered with trace dose of 89Zr-labelled bintrafusp alfa demonstrated the impact of dose and specificity of PD-L1 targeting in vivo. CONCLUSION Molecular imaging of 89Zr-Df-bintrafusp alfa biodistribution was achievable and allows non-invasive quantitation of tumour uptake of 89Zr-Df-bintrafusp alfa, suitable for use in bioimaging clinical trials in cancer patients.
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Affiliation(s)
- Ingrid Julienne Georgette Burvenich
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, 145 Studley Road, Heidelberg, Melbourne, Victoria, 3084, Australia.,School of Cancer Medicine, La Trobe University, Melbourne, Australia
| | - Yit Wooi Goh
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, 145 Studley Road, Heidelberg, Melbourne, Victoria, 3084, Australia
| | - Nancy Guo
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, 145 Studley Road, Heidelberg, Melbourne, Victoria, 3084, Australia
| | - Hui Kong Gan
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, 145 Studley Road, Heidelberg, Melbourne, Victoria, 3084, Australia.,School of Cancer Medicine, La Trobe University, Melbourne, Australia
| | - Angela Rigopoulos
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, 145 Studley Road, Heidelberg, Melbourne, Victoria, 3084, Australia.,School of Cancer Medicine, La Trobe University, Melbourne, Australia
| | - Diana Cao
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, 145 Studley Road, Heidelberg, Melbourne, Victoria, 3084, Australia.,School of Cancer Medicine, La Trobe University, Melbourne, Australia
| | - Zhanqi Liu
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, 145 Studley Road, Heidelberg, Melbourne, Victoria, 3084, Australia.,School of Cancer Medicine, La Trobe University, Melbourne, Australia
| | - Uwe Ackermann
- 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
| | - Christian Werner Wichmann
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, 145 Studley Road, Heidelberg, Melbourne, Victoria, 3084, Australia.,School of Cancer Medicine, La Trobe University, Melbourne, Australia
| | - Alexander Franklin McDonald
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, 145 Studley Road, Heidelberg, Melbourne, Victoria, 3084, Australia.,School of Cancer Medicine, La Trobe University, Melbourne, Australia
| | - Nhi Huynh
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, 145 Studley Road, Heidelberg, Melbourne, Victoria, 3084, Australia
| | - Graeme Joseph O'Keefe
- Department of Molecular Imaging and Therapy, Austin Health, Melbourne, Australia.,Department of Medicine, University of Melbourne, Melbourne, Australia
| | - Sylvia Jie Gong
- Department of Molecular Imaging and Therapy, Austin Health, Melbourne, Australia.,School of Engineering and Mathematical Sciences, La Trobe University, Melbourne, Australia
| | - Fiona Elizabeth Scott
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, 145 Studley Road, Heidelberg, Melbourne, Victoria, 3084, Australia.,School of Cancer Medicine, La Trobe University, Melbourne, Australia
| | - Linghui Li
- EMD Serono Research & Development Institute, Inc., a business of Merck KGaA, Darmstadt, Germany, Billerica, MA, USA
| | - Wanping Geng
- EMD Serono Research & Development Institute, Inc., a business of Merck KGaA, Darmstadt, Germany, Billerica, MA, USA
| | - Anup Zutshi
- EMD Serono Research & Development Institute, Inc., a business of Merck KGaA, Darmstadt, Germany, Billerica, MA, USA
| | - Yan Lan
- EMD Serono Research & Development Institute, Inc., a business of Merck KGaA, Darmstadt, Germany, Billerica, MA, USA
| | - Andrew Mark Scott
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, 145 Studley Road, Heidelberg, Melbourne, Victoria, 3084, 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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