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Bender AA, Kirkeby EK, Cross DJ, Minoshima S, Roberts AG, Mastren TE. Development of a 213Bi-Labeled Pyridyl Benzofuran for Targeted α-Therapy of Amyloid-β Aggregates. J Nucl Med 2024; 65:1467-1472. [PMID: 39054283 DOI: 10.2967/jnumed.124.267482] [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: 01/23/2024] [Accepted: 06/25/2024] [Indexed: 07/27/2024] Open
Abstract
Alzheimer disease is a neurodegenerative disorder with limited treatment options. It is characterized by the presence of several biomarkers, including amyloid-β aggregates, which lead to oxidative stress and neuronal decay. Targeted α-therapy (TAT) has been shown to be efficacious against metastatic cancer. TAT takes advantage of tumor-localized α-particle emission to break disease-associated covalent bonds while minimizing radiation dose to healthy tissues due to the short, micrometer-level, distances traveled. We hypothesized that TAT could be used to break covalent bonds within amyloid-β aggregates and facilitate natural plaque clearance mechanisms. Methods: We synthesized a 213Bi-chelate-linked benzofuran pyridyl derivative (BiBPy) and generated [213Bi]BiBPy, with a specific activity of 120.6 GBq/μg, dissociation constant of 11 ± 1.5 nM, and logP of 0.14 ± 0.03. Results: As the first step toward the validation of [213Bi]BiBPy as a TAT agent for the reduction of Alzheimer disease-associated amyloid-β, we showed that brain homogenates from APP/PS1 double-transgenic male mice (6-9 mo old) incubated with [213Bi]BiBPy exhibited a marked reduction in amyloid-β plaque concentration as measured using both enzyme-linked immunosorbent and Western blotting assays, with a half-maximal effective concentration of 3.72 kBq/pg. Conclusion: This [213Bi]BiBPy-concentration-dependent activity shows that TAT can reduce amyloid plaque concentration in vitro and supports the development of targeting systems for in vivo validations.
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Affiliation(s)
- Aidan A Bender
- Nuclear Engineering Program, University of Utah, Salt Lake City, Utah
| | - Emily K Kirkeby
- Department of Chemistry, University of Utah, Salt Lake City, Utah; and
| | - Donna J Cross
- Department of Radiology, University of Utah, School of Medicine, Salt Lake City, Utah
| | - Satoshi Minoshima
- Department of Radiology, University of Utah, School of Medicine, Salt Lake City, Utah
| | - Andrew G Roberts
- Department of Chemistry, University of Utah, Salt Lake City, Utah; and
| | - Tara E Mastren
- Nuclear Engineering Program, University of Utah, Salt Lake City, Utah;
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2
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Ghosh S, Banerjee D, Guleria A, Chakravarty R. Production, purification and formulation of nanoradiopharmaceutical with 211At: An emerging candidate for targeted alpha therapy. Nucl Med Biol 2024; 138-139:108947. [PMID: 39216162 DOI: 10.1016/j.nucmedbio.2024.108947] [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: 03/12/2024] [Revised: 07/30/2024] [Accepted: 08/22/2024] [Indexed: 09/04/2024]
Abstract
INTRODUCTION Astatine-211 has attained significant interest in the recent times as a promising radioisotope for targeted alpha therapy (TAT) of cancer. In this study, we report the production of 211At via 209Bi (α, 2n) 211At reaction in a cyclotron and development of a facile radiochemical separation procedure to isolate 211At for formulation of nanoradiopharmaceuticals. METHODS Natural bismuth oxide target in pelletized form wrapped in Al foil was irradiated with 30 MeV α-beam in an AVF cyclotron. The irradiated target was dissolved in 2 M HNO3 followed by selective precipitation of Bi as Bi(OH)3 under alkaline condition. The radiochemically separated 211At was used for labeling cyclic RGD peptide conjugated gold nanoparticles (Au-RGD NPs) by surface adsorption. The radiochemical stability of 211At-Au-RGD NPs was evaluated in phosphate buffered saline (PBS) and human serum media. RESULTS The batch yield of 211At at the end of irradiation was ∼6 MBq.μA-1.h-1. After radiochemical separation, ∼80 % of 211At could be retrieved with >99.9 % radionuclidic purity. Au-RGD NPs (particle size 8.4±0.8 nm) could be labeled with 211At with >99 % radiolabeling yield. The radiolabeled nanoparticles retained their integrity in PBS and human serum media over a period of 21 h. CONCLUSIONS The present strategy simplifies 211At production in terms of purification and would increase affordable access to this radioisotope for TAT of cancer.
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Affiliation(s)
- Sanchita Ghosh
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India
| | - Debashis Banerjee
- Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India; Radiochemistry Division (BARC), Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata 700064, India
| | - Apurav Guleria
- Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India; Radiation and Photochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India
| | - Rubel Chakravarty
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India.
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3
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Winter RC, Amghar M, Wacker AS, Bakos G, Taş H, Roscher M, Kelly JM, Benešová-Schäfer M. Future Treatment Strategies for Cancer Patients Combining Targeted Alpha Therapy with Pillars of Cancer Treatment: External Beam Radiation Therapy, Checkpoint Inhibition Immunotherapy, Cytostatic Chemotherapy, and Brachytherapy. Pharmaceuticals (Basel) 2024; 17:1031. [PMID: 39204136 PMCID: PMC11359268 DOI: 10.3390/ph17081031] [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: 06/12/2024] [Revised: 07/22/2024] [Accepted: 07/25/2024] [Indexed: 09/03/2024] Open
Abstract
Cancer is one of the most complex and challenging human diseases, with rising incidences and cancer-related deaths despite improved diagnosis and personalized treatment options. Targeted alpha therapy (TαT) offers an exciting strategy emerging for cancer treatment which has proven effective even in patients with advanced metastatic disease that has become resistant to other treatments. Yet, in many cases, more sophisticated strategies are needed to stall disease progression and overcome resistance to TαT. The combination of two or more therapies which have historically been used as stand-alone treatments is an approach that has been pursued in recent years. This review aims to provide an overview on TαT and the four main pillars of therapeutic strategies in cancer management, namely external beam radiation therapy (EBRT), immunotherapy with checkpoint inhibitors (ICI), cytostatic chemotherapy (CCT), and brachytherapy (BT), and to discuss their potential use in combination with TαT. A brief description of each therapy is followed by a review of known biological aspects and state-of-the-art treatment practices. The emphasis, however, is given to the motivation for combination with TαT as well as the pre-clinical and clinical studies conducted to date.
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Affiliation(s)
- Ruth Christine Winter
- Research Group Molecular Biology of Systemic Radiotherapy/Translational Radiotheranostics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; (R.C.W.); (M.A.); (G.B.); (H.T.)
| | - Mariam Amghar
- Research Group Molecular Biology of Systemic Radiotherapy/Translational Radiotheranostics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; (R.C.W.); (M.A.); (G.B.); (H.T.)
| | - Anja S. Wacker
- Department of Radiology, Molecular Imaging Innovations Institute (MI3), Weill Cornell Medicine, 413 East 69th Street, New York, NY 10021, USA; (A.S.W.); (J.M.K.)
| | - Gábor Bakos
- Research Group Molecular Biology of Systemic Radiotherapy/Translational Radiotheranostics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; (R.C.W.); (M.A.); (G.B.); (H.T.)
| | - Harun Taş
- Research Group Molecular Biology of Systemic Radiotherapy/Translational Radiotheranostics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; (R.C.W.); (M.A.); (G.B.); (H.T.)
| | - Mareike Roscher
- Service Unit for Radiopharmaceuticals and Preclinical Studies, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany;
| | - James M. Kelly
- Department of Radiology, Molecular Imaging Innovations Institute (MI3), Weill Cornell Medicine, 413 East 69th Street, New York, NY 10021, USA; (A.S.W.); (J.M.K.)
| | - Martina Benešová-Schäfer
- Research Group Molecular Biology of Systemic Radiotherapy/Translational Radiotheranostics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; (R.C.W.); (M.A.); (G.B.); (H.T.)
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4
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Matyskin AV, Angermeier SB, Drera SS, Prible MC, Geuther JA, Heibel MD. Actinium-225 photonuclear production in nuclear reactors using a mixed radium-226 and gadolinium-157 target. Nucl Med Biol 2024; 136-137:108940. [PMID: 39002498 DOI: 10.1016/j.nucmedbio.2024.108940] [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: 01/29/2024] [Revised: 06/17/2024] [Accepted: 07/02/2024] [Indexed: 07/15/2024]
Abstract
BACKGROUND Actinium-225 is one of the most promising radionuclides for targeted alpha therapy. Its limited availability significantly restricts clinical trials and potential applications of 225Ac-based radiopharmaceuticals. METHODS In this work, we examine the possibility of 225Ac production from the thermal neutron flux of a nuclear reactor. For this purpose, a target consisting of 1.4 mg of 226Ra(NO3)2 (T1/2 = 1600 years) and 115.5 mg of 90 % enriched, stable 157Gd2O3 was irradiated for 48 h in the Breazeale Nuclear Reactor with an average neutron flux of 1.7·1013 cm-2·s-1. Gadolinium-157 has one of the highest thermal neutron capture cross sections of 0.25 Mb, and its neutron capture results in emission of high-energy, prompt γ-photons. Emitted γ-photons interact with 226Ra to produce 225Ra according to the 226Ra(γ, n)225Ra reaction. Gadolinium debulking and separation of undesirable, co-produced 227Ac from 225Ra was achieved in one step by using 60 g of branched DGA resin. After 225Ac ingrowth from 225Ra (T1/2 = 14.8 d), 225Ac was extracted from the 226Ra and 225Ra fraction using 5 g of bDGA resin and then eluted using 5 mM HNO3. RESULTS Measured activity of 225Ac showed that 6(1) kBq or 0.16(3) μCi (1σ) of 225Ra was produced at the end of bombardment from 0.9 mg of 226Ra. CONCLUSION The developed 225Ac separation is a waste-free process which can be used to obtain pure 225Ac in a nuclear reactor.
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Affiliation(s)
- Artem V Matyskin
- Radiation Science and Engineering Center, College of Engineering, Pennsylvania State University, 100 Breazeale Nuclear Reactor, University Park, PA 16802, United States of America.
| | - Susanna B Angermeier
- Radiation Science and Engineering Center, College of Engineering, Pennsylvania State University, 100 Breazeale Nuclear Reactor, University Park, PA 16802, United States of America; Department of Nuclear Engineering, College of Engineering, Pennsylvania State University, 206 Hallowell Building, University Park, PA 16802, United States of America
| | - Saleem S Drera
- RadTran LLC, 5428 South Idalia Way, Centennial, CO 80015, United States of America
| | - Michael C Prible
- Westinghouse Electric Company LLC, 1000 Westinghouse Drive, Cranberry Township, PA 16066, United States of America
| | - Jeffrey A Geuther
- Radiation Science and Engineering Center, College of Engineering, Pennsylvania State University, 100 Breazeale Nuclear Reactor, University Park, PA 16802, United States of America
| | - Michael D Heibel
- Westinghouse Electric Company LLC, 1000 Westinghouse Drive, Cranberry Township, PA 16066, United States of America
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5
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Bergeron DE, Cessna JT, Broder BA, Pibida L, Fitzgerald RP, DiGiorgio M, Napoli E, Zimmerman BE. Activity standard and calibrations for 227Th with ingrowing progeny. Appl Radiat Isot 2024; 209:111326. [PMID: 38701595 DOI: 10.1016/j.apradiso.2024.111326] [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: 01/03/2024] [Revised: 03/10/2024] [Accepted: 04/10/2024] [Indexed: 05/05/2024]
Abstract
Thorium-227 was separated from its progeny and standardized for activity by the triple-to-double coincidence ratio (TDCR) method of liquid scintillation counting. Confirmatory liquid scintillation-based measurements were made using efficiency tracing with 3H and live-timed anticoincidence counting (LTAC). The separation time and the efficiency of the separation were confirmed by gamma-ray spectrometry. Calibrations for reentrant pressurized ionization chambers, including commercial radionuclide calibrators, and a well-type NaI(Tl) detector are discussed.
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Affiliation(s)
- Denis E Bergeron
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
| | - Jeffrey T Cessna
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Brittany A Broder
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Leticia Pibida
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Ryan P Fitzgerald
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Morgan DiGiorgio
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | | | - Brian E Zimmerman
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
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6
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Qiu L, Wu J, Luo N, Xiao Q, Geng J, Xia L, Liao J, Yang Y, Liu N, Zhang J, Li F. Preparation of Medical 228Th- 224Ra Radionuclide Generator Based on SiO 2@TiO 2 Microspheres. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:11723-11731. [PMID: 38775311 DOI: 10.1021/acs.langmuir.4c01138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2024]
Abstract
224Ra (T1/2 = 3.63 d), an α-emitting radionuclide, holds significant promise in cancer endoradiotherapy. Current 224Ra-related therapy is still scarce because of the lack of reliable radionuclide supply. The 228Th-224Ra radionuclide generator can undoubtedly introduce continuous and sustainable availability of 224Ra for advanced nuclear medicine. However, conventional metal oxides for such radionuclide generators manifest suboptimal adsorption capacities for the parent nuclide, primarily attributable to their limited surface area. In this work, core-shell SiO2@TiO2 microspheres were proposed to develop as column materials for the construction of a 228Th-224Ra generator. SiO2@TiO2 microspheres were well prepared and systematically characterized, which has also been demonstrated to have good adsorption capacity to 228Th and very weak binding affinity toward 224Ra via simulated chemical separation. Upon introducing 228Th-containing solution onto the SiO2@TiO2 functional column, a 228Th-224Ra generator with excellent retention of the parent radionuclide and ideal elution efficiency of daughter radionuclide was obtained. The prepared 228Th-224Ra generator can produce 224Ra with high purity and medical usability in good elution efficiency (98.72%) even over five cycles. To the best of our knowledge, this is the first time that the core-shell mesoporous materials have been applied in a radionuclide generator, which can offer valuable insights for materials chemistry, radiochemical separation, and biological medicine.
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Affiliation(s)
- Long Qiu
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, China
- Sichuan Engineering Research Center for Radioactive Isotope, National Engineering Research Center for Isotopes and Pharmaceuticals, Nuclear Power Institute of China, Chengdu 610005, China
| | - Jianrong Wu
- Sichuan Engineering Research Center for Radioactive Isotope, National Engineering Research Center for Isotopes and Pharmaceuticals, Nuclear Power Institute of China, Chengdu 610005, China
| | - Ning Luo
- Sichuan Engineering Research Center for Radioactive Isotope, National Engineering Research Center for Isotopes and Pharmaceuticals, Nuclear Power Institute of China, Chengdu 610005, China
| | - Qian Xiao
- Sichuan Engineering Research Center for Radioactive Isotope, National Engineering Research Center for Isotopes and Pharmaceuticals, Nuclear Power Institute of China, Chengdu 610005, China
| | - Junshan Geng
- Sichuan Engineering Research Center for Radioactive Isotope, National Engineering Research Center for Isotopes and Pharmaceuticals, Nuclear Power Institute of China, Chengdu 610005, China
| | - Lingting Xia
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, China
| | - Jiali Liao
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, China
| | - Yuanyou Yang
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, China
| | - Ning Liu
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, China
| | - Jinsong Zhang
- Sichuan Engineering Research Center for Radioactive Isotope, National Engineering Research Center for Isotopes and Pharmaceuticals, Nuclear Power Institute of China, Chengdu 610005, China
| | - Feize Li
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, China
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7
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Ree SM, Greenwood H, Young JD, Roberts R, Livens FR, Heath SL, Sosabowski JK. Selection of radionuclide(s) for targeted alpha therapy based on their nuclear decay properties. Nucl Med Commun 2024; 45:465-473. [PMID: 38465420 DOI: 10.1097/mnm.0000000000001832] [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: 03/12/2024]
Abstract
Targeted alpha therapy (TAT) is a promising form of oncology treatment utilising alpha-emitting radionuclides that can specifically accumulate at disease sites. The high energy and high linear energy transfer associated with alpha emissions causes localised damage at target sites whilst minimising that to surrounding healthy tissue. The lack of appropriate radionuclides has inhibited research in TAT. The identification of appropriate radionuclides should be primarily a function of the radionuclide's nuclear decay properties, and not their biochemistry or economic factors since these last two factors can change; however, the nuclear decay properties are fixed to that nuclide. This study has defined and applied a criterion based on nuclear decay properties useful for TAT. This down-selection exercise concluded that the most appropriate radionuclides are: 149 Tb, 211 At/ 211 Po, 212 Pb/ 212 Bi/ 212 Po, 213 Bi/ 213 Po, 224 Ra, 225 Ra/ 225 Ac/ 221 Fr, 226 Ac/ 226 Th, 227 Th/ 223 Ra/ 219 Rn, 229 U, 230 U/ 226 Th, and 253 Fm, the majority of which have previously been considered for TAT. 229 U and 253 Fm have been newly identified and could become new radionuclides of interest for TAT, depending on their decay chain progeny.
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Affiliation(s)
- Samantha M Ree
- National Nuclear Laboratory, Springfields, Salwick, Preston, Lancashire
| | - Howard Greenwood
- National Nuclear Laboratory, Springfields, Salwick, Preston, Lancashire
| | - Jennifer D Young
- School of Biomedical Engineering and Imaging Sciences, King's College London, London
| | - Rachel Roberts
- National Nuclear Laboratory, Springfields, Salwick, Preston, Lancashire
| | | | - Scott L Heath
- Department of Earth and Environmental Sciences, The University of Manchester, Manchester and
| | - Jane K Sosabowski
- Centre for Cancer Biomarkers and Biotherapeutics, Barts Cancer Institute, Queen Mary University of London, London
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8
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Kleynhans J, Ebenhan T, Cleeren F, Sathekge MM. Can current preclinical strategies for radiopharmaceutical development meet the needs of targeted alpha therapy? Eur J Nucl Med Mol Imaging 2024; 51:1965-1980. [PMID: 38676735 PMCID: PMC11139742 DOI: 10.1007/s00259-024-06719-5] [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: 02/22/2024] [Accepted: 04/15/2024] [Indexed: 04/29/2024]
Abstract
Preclinical studies are essential for effectively evaluating TAT radiopharmaceuticals. Given the current suboptimal supply chain of these radionuclides, animal studies must be refined to produce the most translatable TAT agents with the greatest clinical potential. Vector design is pivotal, emphasizing harmonious physical and biological characteristics among the vector, target, and radionuclide. The scarcity of alpha-emitting radionuclides remains a significant consideration. Actinium-225 and lead-212 appear as the most readily available radionuclides at this stage. Available animal models for researchers encompass xenografts, allografts, and PDX (patient-derived xenograft) models. Emerging strategies for imaging alpha-emitters are also briefly explored. Ultimately, preclinical research must address two critical aspects: (1) offering valuable insights into balancing safety and efficacy, and (2) providing guidance on the optimal dosing of the TAT agent.
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Affiliation(s)
- Janke Kleynhans
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, 3000, Belgium
| | - Thomas Ebenhan
- Department of Nuclear Medicine, University of Pretoria, and Steve Biko Academic Hospital, Pretoria, 0001, South Africa
- Department of Nuclear Medicine, Steve Biko Academic Hospital, Pretoria, 0001, South Africa
| | - Frederik Cleeren
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, 3000, Belgium
| | - Mike Machaba Sathekge
- Department of Nuclear Medicine, Steve Biko Academic Hospital, Pretoria, 0001, South Africa.
- Preclinical Imaging Facility, Nuclear Medicine Research Infrastructure, Pretoria, 0001, South Africa.
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9
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Jajčišinová E, Dockx K, Au M, Bara S, Cocolios TE, Chrysalidis K, Farooq-Smith GJ, Fedorov DV, Fedosseev VN, Flanagan KT, Heines M, Houngbo D, Johnson JD, Kellerbauer A, Kraemer S, Marsh BA, Popescu L, Ramos JP, Rothe S, Seliverstov MD, Sels S, Stegemann S, Stryjczyk M, Verelst V. Production study of Fr, Ra and Ac radioactive ion beams at ISOLDE, CERN. Sci Rep 2024; 14:11033. [PMID: 38744912 PMCID: PMC11094045 DOI: 10.1038/s41598-024-60331-z] [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: 01/25/2024] [Accepted: 04/22/2024] [Indexed: 05/16/2024] Open
Abstract
The presented paper discusses the production of radioactive ion beams of francium, radium, and actinium from thick uranium carbide (UCx ) targets at ISOLDE, CERN. This study focuses on the release curves and extractable yields of francium, radium and actinium isotopes. The ion source temperature was varied in order to study the relative contributions of surface and laser ionization to the production of the actinium ion beams. The experimental results are presented in the form of release parameters. Representative extractable yields per μ C are presented for222 - 231 Ac, several Ra and Fr isotopes in the mass ranges 214 ≤ A ≤ 233 and 205 ≤ A ≤ 231 respectively. The release efficiency for several isotopes of each of the studied elements was calculated by comparing their yields to the estimated in-target production rates modeled by CERN-FLUKA. The maximal extraction efficiency of actinium was calculated to be 2.1(6)% for a combination of surface ionization using a Ta ion source and resonant laser ionization using the two-step 438.58 nm, and 424.69 nm scheme.
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Affiliation(s)
- E Jajčišinová
- European Commission, Joint Research Centre (JRC), Karlsruhe, Germany.
- KU Leuven, Instituut voor Kern- en Stralingsfysica, Leuven, Belgium.
| | - K Dockx
- KU Leuven, Instituut voor Kern- en Stralingsfysica, Leuven, Belgium
| | - M Au
- CERN, Geneva 23, Switzerland
| | - S Bara
- KU Leuven, Instituut voor Kern- en Stralingsfysica, Leuven, Belgium
| | - T E Cocolios
- KU Leuven, Instituut voor Kern- en Stralingsfysica, Leuven, Belgium.
| | | | - G J Farooq-Smith
- KU Leuven, Instituut voor Kern- en Stralingsfysica, Leuven, Belgium
- Department of Oncology Physics, Edinburgh Cancer Centre, Edinburgh, UK
| | - D V Fedorov
- Affiliated with an institute covered by a cooperation agreement with CERN, Geneva, Switzerland
| | | | - K T Flanagan
- Photon Science Institute, Department of Physics and Astronomy, University of Manchester, Manchester, UK
| | - M Heines
- KU Leuven, Instituut voor Kern- en Stralingsfysica, Leuven, Belgium
| | | | - J D Johnson
- KU Leuven, Instituut voor Kern- en Stralingsfysica, Leuven, Belgium
| | - A Kellerbauer
- European Commission, Joint Research Centre (JRC), Karlsruhe, Germany
| | - S Kraemer
- KU Leuven, Instituut voor Kern- en Stralingsfysica, Leuven, Belgium
| | | | | | - J P Ramos
- KU Leuven, Instituut voor Kern- en Stralingsfysica, Leuven, Belgium
- CERN, Geneva 23, Switzerland
- SCK CEN, Mol, Belgium
| | - S Rothe
- CERN, Geneva 23, Switzerland
| | - M D Seliverstov
- Affiliated with an institute covered by a cooperation agreement with CERN, Geneva, Switzerland
| | - S Sels
- KU Leuven, Instituut voor Kern- en Stralingsfysica, Leuven, Belgium
| | - S Stegemann
- KU Leuven, Instituut voor Kern- en Stralingsfysica, Leuven, Belgium
- CERN, Geneva 23, Switzerland
| | - M Stryjczyk
- KU Leuven, Instituut voor Kern- en Stralingsfysica, Leuven, Belgium
- University of Jyvaskyla, Department of Physics, Accelerator laboratory, Jyvaskyla, Finland
| | - V Verelst
- KU Leuven, Instituut voor Kern- en Stralingsfysica, Leuven, Belgium
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10
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Munekane M, Fuchigami T, Ogawa K. Recent advances in the development of 225Ac- and 211At-labeled radioligands for radiotheranostics. ANAL SCI 2024; 40:803-826. [PMID: 38564087 PMCID: PMC11035452 DOI: 10.1007/s44211-024-00514-w] [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: 11/28/2023] [Accepted: 01/16/2024] [Indexed: 04/04/2024]
Abstract
Radiotheranostics utilizes a set of radioligands incorporating diagnostic or therapeutic radionuclides to achieve both diagnosis and therapy. Imaging probes using diagnostic radionuclides have been used for systemic cancer imaging. Integration of therapeutic radionuclides into the imaging probes serves as potent agents for radionuclide therapy. Among them, targeted alpha therapy (TAT) is a promising next-generation cancer therapy. The α-particles emitted by the radioligands used in TAT result in a high linear energy transfer over a short range, inducing substantial damage to nearby cells surrounding the binding site. Therefore, the key to successful cancer treatment with minimal side effects by TAT depends on the selective delivery of radioligands to their targets. Recently, TAT agents targeting biomolecules highly expressed in various cancer cells, such as sodium/iodide symporter, norepinephrine transporter, somatostatin receptor, αvβ3 integrin, prostate-specific membrane antigen, fibroblast-activation protein, and human epidermal growth factor receptor 2 have been developed and have made remarkable progress toward clinical application. In this review, we focus on two radionuclides, 225Ac and 211At, which are expected to have a wide range of applications in TAT. We also introduce recent fundamental and clinical studies of radiopharmaceuticals labeled with these radionuclides.
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Affiliation(s)
- Masayuki Munekane
- Graduate School of Medical Sciences, Kanazawa University, Kakuma-Machi, Kanazawa, Ishikawa, 920-1192, Japan
| | - Takeshi Fuchigami
- Graduate School of Medical Sciences, Kanazawa University, Kakuma-Machi, Kanazawa, Ishikawa, 920-1192, Japan.
| | - Kazuma Ogawa
- Graduate School of Medical Sciences, Kanazawa University, Kakuma-Machi, Kanazawa, Ishikawa, 920-1192, Japan.
- Institute for Frontier Science Initiative, Kanazawa University, Kakuma-Machi, Kanazawa, Ishikawa, 920-1192, Japan.
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11
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Gape PMD, Schultz MK, Stasiuk GJ, Terry SYA. Towards Effective Targeted Alpha Therapy for Neuroendocrine Tumours: A Review. Pharmaceuticals (Basel) 2024; 17:334. [PMID: 38543120 PMCID: PMC10974115 DOI: 10.3390/ph17030334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 02/22/2024] [Accepted: 02/26/2024] [Indexed: 04/01/2024] Open
Abstract
This review article explores the evolving landscape of Molecular Radiotherapy (MRT), emphasizing Peptide Receptor Radionuclide Therapy (PRRT) for neuroendocrine tumours (NETs). The primary focus is on the transition from β-emitting radiopharmaceuticals to α-emitting agents in PRRT, offering a critical analysis of the radiobiological basis, clinical applications, and ongoing developments in Targeted Alpha Therapy (TAT). Through an extensive literature review, the article delves into the mechanisms and effectiveness of PRRT in targeting somatostatin subtype 2 receptors, highlighting both its successes and limitations. The discussion extends to the emerging paradigm of TAT, underlining its higher potency and specificity with α-particle emissions, which promise enhanced therapeutic efficacy and reduced toxicity. The review critically evaluates preclinical and clinical data, emphasizing the need for standardised dosimetry and a deeper understanding of the dose-response relationship in TAT. The review concludes by underscoring the significant potential of TAT in treating SSTR2-overexpressing cancers, especially in patients refractory to β-PRRT, while also acknowledging the current challenges and the necessity for further research to optimize treatment protocols.
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Affiliation(s)
- Paul M. D. Gape
- School of Biomedical Engineering & Imaging Sciences, King’s College London, London SE1 7EP, UK; (G.J.S.); (S.Y.A.T.)
| | - Michael K. Schultz
- Departments of Radiology, Radiation Oncology, Free Radical and Radiation Biology Program, University of Iowa, Iowa City, IA 52242, USA;
- Perspective Therapeutics, Coralville, IA 52241, USA
| | - Graeme J. Stasiuk
- School of Biomedical Engineering & Imaging Sciences, King’s College London, London SE1 7EP, UK; (G.J.S.); (S.Y.A.T.)
| | - Samantha Y. A. Terry
- School of Biomedical Engineering & Imaging Sciences, King’s College London, London SE1 7EP, UK; (G.J.S.); (S.Y.A.T.)
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12
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Dyer MR, Jing Z, Duncan K, Godbe J, Shokeen M. Advancements in the development of radiopharmaceuticals for nuclear medicine applications in the treatment of bone metastases. Nucl Med Biol 2024; 130-131:108879. [PMID: 38340369 DOI: 10.1016/j.nucmedbio.2024.108879] [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: 10/20/2023] [Revised: 01/25/2024] [Accepted: 01/30/2024] [Indexed: 02/12/2024]
Abstract
Bone metastases are a painful and complex condition that overwhelmingly impacts the prognosis and quality of life of cancer patients. Over the years, nuclear medicine has made remarkable progress in the diagnosis and management of bone metastases. This review aims to provide a comprehensive overview of the recent advancements in nuclear medicine for the diagnosis and management of bone metastases. Furthermore, the review explores the role of targeted radiopharmaceuticals in nuclear medicine for bone metastases, focusing on radiolabeled molecules that are designed to selectively target biomarkers associated with bone metastases, including osteocytes, osteoblasts, and metastatic cells. The applications of radionuclide-based therapies, such as strontium-89 (Sr-89) and radium-223 (Ra-223), are also discussed. This review also highlights the potential of theranostic approaches for bone metastases, enabling personalized treatment strategies based on individual patient characteristics. Importantly, the clinical applications and outcomes of nuclear medicine in osseous metastatic disease are discussed. This includes the assessment of treatment response, predictive and prognostic value of imaging biomarkers, and the impact of nuclear medicine on patient management and outcomes. The review identifies current challenges and future perspectives on the role of nuclear medicine in treating bone metastases. It addresses limitations in imaging resolution, radiotracer availability, radiation safety, and the need for standardized protocols. The review concludes by emphasizing the need for further research and advancements in imaging technology, radiopharmaceutical development, and integration of nuclear medicine with other treatment modalities. In summary, advancements in nuclear medicine have significantly improved the diagnosis and management of osseous metastatic disease and future developements in the integration of innovative imaging modalities, targeted radiopharmaceuticals, radionuclide production, theranostic approaches, and advanced image analysis techniques hold great promise in improving patient outcomes and enhancing personalized care for individuals with bone metastases.
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Affiliation(s)
- Michael R Dyer
- Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Zhenghan Jing
- Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Kathleen Duncan
- Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Jacqueline Godbe
- Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Monica Shokeen
- Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA; Alvin J. Siteman Cancer Center, Washington University School of Medicine and Barnes-Jewish Hospital, St. Louis, MO 63110, USA; Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO 63110, USA; Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA.
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13
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Hooijman EL, Radchenko V, Ling SW, Konijnenberg M, Brabander T, Koolen SLW, de Blois E. Implementing Ac-225 labelled radiopharmaceuticals: practical considerations and (pre-)clinical perspectives. EJNMMI Radiopharm Chem 2024; 9:9. [PMID: 38319526 PMCID: PMC10847084 DOI: 10.1186/s41181-024-00239-1] [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: 07/20/2023] [Accepted: 01/25/2024] [Indexed: 02/07/2024] Open
Abstract
BACKGROUND In the past years, there has been a notable increase in interest regarding targeted alpha therapy using Ac-225, driven by the observed promising clinical anti-tumor effects. As the production and technology has advanced, the availability of Ac-225 is expected to increase in the near future, making the treatment available to patients worldwide. MAIN BODY Ac-225 can be labelled to different biological vectors, whereby the success of developing a radiopharmaceutical depends heavily on the labelling conditions, purity of the radionuclide source, chelator, and type of quenchers used to avoid radiolysis. Multiple (methodological) challenges need to be overcome when working with Ac-225; as alpha-emission detection is time consuming and highly geometry dependent, a gamma co-emission is used, but has to be in equilibrium with the mother-nuclide. Because of the high impact of alpha emitters in vivo it is highly recommended to cross-calibrate the Ac-225 measurements for used quality control (QC) techniques (radio-TLC, HPLC, HP-Ge detector, and gamma counter). More strict health physics regulations apply, as Ac-225 has a high toxicity, thereby limiting practical handling and quantities used for QC analysis. CONCLUSION This overview focuses specifically on the practical and methodological challenges when working with Ac-225 labelled radiopharmaceuticals, and underlines the required infrastructure and (detection) methods for the (pre-)clinical application.
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Affiliation(s)
- Eline L Hooijman
- Department of Radiology and Nuclear Medicine, Erasmus MC, 3015 CN, Rotterdam, The Netherlands
- Department of Hospital Pharmacy, Erasmus MC, 3015 CN, Rotterdam, The Netherlands
| | - Valery Radchenko
- Life Sciences Division, TRIUMF, Vancouver, BC, V6T 2A3, Canada
- Chemistry Department, University of British Columbia, Vancouver, BC, V6T 1Z1, Canada
| | - Sui Wai Ling
- Department of Radiology and Nuclear Medicine, Erasmus MC, 3015 CN, Rotterdam, The Netherlands
| | - Mark Konijnenberg
- Department of Radiology and Nuclear Medicine, Erasmus MC, 3015 CN, Rotterdam, The Netherlands
| | - Tessa Brabander
- Department of Radiology and Nuclear Medicine, Erasmus MC, 3015 CN, Rotterdam, The Netherlands
| | - Stijn L W Koolen
- Department of Radiology and Nuclear Medicine, Erasmus MC, 3015 CN, Rotterdam, The Netherlands
- Department of Hospital Pharmacy, Erasmus MC, 3015 CN, Rotterdam, The Netherlands
- Department of Medical Oncology, Erasmus MC Cancer Institute, 3015 CN, Rotterdam, The Netherlands
| | - Erik de Blois
- Department of Radiology and Nuclear Medicine, Erasmus MC, 3015 CN, Rotterdam, The Netherlands.
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14
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Vogt J, Oeh U, Maringer FJ. Development of the occupational exposure during the production and application of radiopharmaceuticals in Germany. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2024; 44:011508. [PMID: 38232404 DOI: 10.1088/1361-6498/ad1fdd] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Accepted: 01/17/2024] [Indexed: 01/19/2024]
Abstract
An increasing number of radiopharmaceuticals and proteins are available for diagnosing and treating various diseases. The demand for existing and newly developed pharmaceutical radionuclides and proteins is steadily increasing. The radiation exposure levels of workers in the radiopharmaceutical industry and nuclear medicine field are closely monitored, specifically their effective dose and equivalent dose, leading to the question, of whether the dawn of radiopharmaceuticals affects the occupational exposure level. This development is analyzed and evaluated with data from the German National Dose Register. Data shows that the effective dose in the work categories production and distribution of radioisotopes as well as nuclear medicine slightly decreased from 1997 to 2021. Over the same period, the hand equivalent dose in nuclear medicine increases steadily, with no discernible trend in production and distribution of radioisotopes. Over the past few decades, intentional efforts and measures have been taken to ensure radiation protection. Instruments for monitoring and dose reduction must be continuously applied. Given the low effective dose, the focus in future shall be on dose reduction following theaslowasreasonablyachievable principle. The development of the hand equivalent dose should be carefully observed in the upcoming years.
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Affiliation(s)
- Julius Vogt
- Emergency Preparedness & Response, Federal Office for Radiation Protection, Köpenicker Allee 120 - 130, Berlin 10318, Germany
- University of Vienna, Universitätsstraße 7, Wien 1010, Austria
| | - Uwe Oeh
- Medical and Occupational Radiation Protection, Federal Office for Radiation Protection, Ingolstädter Landstraße 1, Oberschleißheim 85764, Germany
| | - Franz Josef Maringer
- Atominstitut, TU Wien,, Stadionallee 2, Wien 1020, Austria
- University of Natural Resources and Life Sciences (BOKU), Peter-Jordan-Straße 82, Wien 1190, Austria
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15
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Kaneda-Nakashima K, Shirakami Y, Kadonaga Y, Watabe T, Ooe K, Yin X, Haba H, Shirasaki K, Kikunaga H, Tsukada K, Toyoshima A, Cardinale J, Giesel FL, Fukase K. Comparison of Nuclear Medicine Therapeutics Targeting PSMA among Alpha-Emitting Nuclides. Int J Mol Sci 2024; 25:933. [PMID: 38256007 PMCID: PMC10815831 DOI: 10.3390/ijms25020933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 01/05/2024] [Accepted: 01/07/2024] [Indexed: 01/24/2024] Open
Abstract
Currently, targeted alpha therapy (TAT) is a new therapy involving the administration of a therapeutic drug that combines a substance of α-emitting nuclides that kill cancer cells and a drug that selectively accumulates in cancer cells. It is known to be effective against cancers that are difficult to treat with existing methods, such as cancer cells that are widely spread throughout the whole body, and there are high expectations for its early clinical implementation. The nuclides for TAT, including 149Tb, 211At, 212/213Bi, 212Pb (for 212Bi), 223Ra, 225Ac, 226/227Th, and 230U, are known. However, some nuclides encounter problems with labeling methods and lack sufficient preclinical and clinical data. We labeled the compounds targeting prostate specific membrane antigen (PSMA) with 211At and 225Ac. PSMA is a molecule that has attracted attention as a theranostic target for prostate cancer, and several targeted radioligands have already shown therapeutic effects in patients. The results showed that 211At, which has a much shorter half-life, is no less cytotoxic than 225Ac. In 211At labeling, our group has also developed an original method (Shirakami Reaction). We have succeeded in obtaining a highly purified labeled product in a short timeframe using this method.
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Affiliation(s)
- Kazuko Kaneda-Nakashima
- Laboratory of Radiation Biological Chemistry, FRC, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan
- MS-CORE, FRC, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan; (Y.S.); (Y.K.); (T.W.); (K.O.); (A.T.); (K.F.)
- Department of Science, Institute for Radiation Sciences, Osaka University, Suita 565-0871, Japan
| | - Yoshifumi Shirakami
- MS-CORE, FRC, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan; (Y.S.); (Y.K.); (T.W.); (K.O.); (A.T.); (K.F.)
- Department of Science, Institute for Radiation Sciences, Osaka University, Suita 565-0871, Japan
| | - Yuichiro Kadonaga
- MS-CORE, FRC, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan; (Y.S.); (Y.K.); (T.W.); (K.O.); (A.T.); (K.F.)
- Nuclear Medicine, Graduate School of Medicine, Osaka University, Suita 565-0871, Japan
| | - Tadashi Watabe
- MS-CORE, FRC, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan; (Y.S.); (Y.K.); (T.W.); (K.O.); (A.T.); (K.F.)
- Nuclear Medicine, Graduate School of Medicine, Osaka University, Suita 565-0871, Japan
| | - Kazuhiro Ooe
- MS-CORE, FRC, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan; (Y.S.); (Y.K.); (T.W.); (K.O.); (A.T.); (K.F.)
- Radioisotope Research Center, Institute for Radiation Sciences, Osaka University, Suita 565-0871, Japan
| | - Xiaojie Yin
- Nishina Center for Accelerator-Based Science Nuclear Chemistry Group, RIKEN, Wako 351-0198, Japan; (X.Y.); (H.H.)
| | - Hiromitsu Haba
- Nishina Center for Accelerator-Based Science Nuclear Chemistry Group, RIKEN, Wako 351-0198, Japan; (X.Y.); (H.H.)
| | - Kenji Shirasaki
- Laboratory of Alpha-Ray Emitters, Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan;
| | - Hidetoshi Kikunaga
- Research Center for Electron Photon Science, Tohoku University, Sendai 982-0826, Japan;
| | - Kazuaki Tsukada
- Research Group of Heavy Element Nuclear Science, Advanced Science Research Center, Japan Atomic Energy Agency, Naka-gun 319-1195, Japan;
| | - Atsushi Toyoshima
- MS-CORE, FRC, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan; (Y.S.); (Y.K.); (T.W.); (K.O.); (A.T.); (K.F.)
- Department of Science, Institute for Radiation Sciences, Osaka University, Suita 565-0871, Japan
| | - Jens Cardinale
- Nuclear Medicine Department, University Hospital Düsseldorf, 40225 Düsseldorf, Germany; (J.C.); (F.L.G.)
| | - Frederik L. Giesel
- Nuclear Medicine Department, University Hospital Düsseldorf, 40225 Düsseldorf, Germany; (J.C.); (F.L.G.)
| | - Koichi Fukase
- MS-CORE, FRC, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan; (Y.S.); (Y.K.); (T.W.); (K.O.); (A.T.); (K.F.)
- Department of Science, Institute for Radiation Sciences, Osaka University, Suita 565-0871, Japan
- Natural Product Chemistry, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan
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16
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Galea R, Moore K. Primary standardization and half-life determination of 225Ac at NRC. Appl Radiat Isot 2024; 203:111105. [PMID: 37949013 DOI: 10.1016/j.apradiso.2023.111105] [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: 06/28/2023] [Revised: 10/12/2023] [Accepted: 11/01/2023] [Indexed: 11/12/2023]
Abstract
A solution of 225Ac was standardized by NRC using the triple-to-double coincidence ratio (TDCR) method. The counting efficiencies were calculated assuming a counting efficiency of 100% for alpha decays and those calculated using the MICELLE2 Monte Carlo code for beta decays and was approximately 500% for the NRC TDCR system. The relative uncertainty for the activity concentration was determined to be 0.25%. This agreed with measurements performed using gamma spectroscopy and a predicted calibration factor for the Vinten 671 ionization chamber as calculated using an EGSnrc model, implementing radioactive decay. Finally, the half-life of 225Ac was determined from long-term measurements using ionization chambers and liquid scintillation counting. The NRC measured half-life for 225Ac was found to be 9.914(4) days and is consistent within an expanded uncertainty coverage of k = 2 with the most recent (Kossert et al., 2020; Pommé et al., 2012) measurements of this decay parameter.
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Affiliation(s)
- R Galea
- National Research Council of Canada, 1200 Montreal Road, Ottawa, K1A0R6, ON, Canada.
| | - K Moore
- National Research Council of Canada, 1200 Montreal Road, Ottawa, K1A0R6, ON, Canada
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17
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Rabiei M, Asadi M, Yousefnia H. Astatine-211 Radiopharmaceuticals; Status, Trends, and the Future. Curr Radiopharm 2024; 17:7-13. [PMID: 37937552 DOI: 10.2174/0118744710262325231025075638] [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: 03/15/2023] [Revised: 08/12/2023] [Accepted: 09/15/2023] [Indexed: 11/09/2023]
Abstract
The low range of alpha particles provides an opportunity to better target cancer cells theoretically leading to the introduction of interesting alpha emitter radiopharmaceuticals including 225Ac, 212Pb, etc. The combination of high energy and short range of alpha emitters differentiates targeted radiotherapy from other methods and reduces unwanted cytotoxicity of the cells around the tumoral tissue. Among interesting alpha emitters candidates for targeted therapy, 211At, one of the radioisotopes with the best optimal decay properties, shows great promise for targeted radiotherapy in some animal prostate cancer xenograft studies and bone micro tumors with significant effects compared to other beta and alpha emitters and also demonstrates interesting properties for clinical applications. However, production and application of this alpha emitter in the development of actinium-based radiopharmaceuticals is hampered by many obstacles. This mini-review demonstrates 211At production methods, chemical separation, radiolabeling procedures, 211At-radiopharmaceuticals and their clinical trials, transport, logistics, and costs and future trends in the field for ultimate clinical applications. This review showed that there are limited clinical trials on 211Ac-based radiopharmaceuticals, which is due to the low accessibility of this radioisotope and other limitations. However, the development programs of major industries indicate the development of 211Ac-based radiopharmaceuticals in the future.
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Affiliation(s)
- Mobina Rabiei
- Nuclear Engineering School, Islamic Azad University Shahrood Branch, Shahrud, Iran
| | - Mahboobeh Asadi
- Research Center for Nuclear Medicine, Shariati Hospital, Tehran University of Medical Science, Tehran, Iran
| | - Hassan Yousefnia
- Radiation Application Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran, Iran
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18
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Woods JJ, Cosby AG, Wacker JN, Aguirre Quintana LM, Peterson A, Minasian SG, Abergel RJ. Macrocyclic 1,2-Hydroxypyridinone-Based Chelators as Potential Ligands for Thorium-227 and Zirconium-89 Radiopharmaceuticals. Inorg Chem 2023; 62:20721-20732. [PMID: 37590371 DOI: 10.1021/acs.inorgchem.3c02164] [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: 08/19/2023]
Abstract
Thorium-227 (227Th) is an α-emitting radionuclide that has shown preclinical and clinical promise for use in targeted α-therapy (TAT), a type of molecular radiopharmaceutical treatment that harnesses high energy α particles to eradicate cancerous lesions. Despite these initial successes, there still exists a need for bifunctional chelators that can stably bind thorium in vivo. Toward this goal, we have prepared two macrocyclic chelators bearing 1,2-hydroxypyridinone groups. Both chelators can be synthesized in less than six steps from readily available starting materials, which is an advantage over currently available platforms. The complex formation constants (log βmlh) of these ligands with Zr4+ and Th4+, measured by spectrophotometric titrations, are greater than 34 for both chelators, indicating the formation of exceedingly stable complexes. Radiolabeling studies were performed to show that these ligands can bind [227Th]Th4+ at concentrations as low as 10-6 M, and serum stability experiments demonstrate the high kinetic stability of the formed complexes under biological conditions. Identical experiments with zirconium-89 (89Zr), a positron-emitting radioisotope used for positron emission tomography (PET) imaging, demonstrate that these chelators can also effectively bind Zr4+ with high thermodynamic and kinetic stability. Collectively, the data reported herein highlight the suitability of these ligands for use in 89Zr/227Th paired radioimmunotheranostics.
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Affiliation(s)
- Joshua J Woods
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Alexia G Cosby
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Jennifer N Wacker
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Luis M Aguirre Quintana
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Appie Peterson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Stefan G Minasian
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Rebecca J Abergel
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Nuclear Engineering, University of California Berkeley, Berkeley, California 94720, United States
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19
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Nelson BJB, Wilson J, Andersson JD, Wuest F. Theranostic Imaging Surrogates for Targeted Alpha Therapy: Progress in Production, Purification, and Applications. Pharmaceuticals (Basel) 2023; 16:1622. [PMID: 38004486 PMCID: PMC10674391 DOI: 10.3390/ph16111622] [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: 10/11/2023] [Revised: 11/08/2023] [Accepted: 11/14/2023] [Indexed: 11/26/2023] Open
Abstract
This article highlights recent developments of SPECT and PET diagnostic imaging surrogates for targeted alpha particle therapy (TAT) radiopharmaceuticals. It outlines the rationale for using imaging surrogates to improve diagnostic-scan accuracy and facilitate research, and the properties an imaging-surrogate candidate should possess. It evaluates the strengths and limitations of each potential imaging surrogate. Thirteen surrogates for TAT are explored: 133La, 132La, 134Ce/134La, and 226Ac for 225Ac TAT; 203Pb for 212Pb TAT; 131Ba for 223Ra and 224Ra TAT; 123I, 124I, 131I and 209At for 211At TAT; 134Ce/134La for 227Th TAT; and 155Tb and 152Tb for 149Tb TAT.
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Affiliation(s)
- Bryce J. B. Nelson
- Department of Oncology, University of Alberta, 11560 University Ave., Edmonton, AB T6G 1Z2, Canada; (B.J.B.N.); (J.W.); (J.D.A.)
| | - John Wilson
- Department of Oncology, University of Alberta, 11560 University Ave., Edmonton, AB T6G 1Z2, Canada; (B.J.B.N.); (J.W.); (J.D.A.)
| | - Jan D. Andersson
- Department of Oncology, University of Alberta, 11560 University Ave., Edmonton, AB T6G 1Z2, Canada; (B.J.B.N.); (J.W.); (J.D.A.)
- Edmonton Radiopharmaceutical Center, Alberta Health Services, 11560 University Ave., Edmonton, AB T6G 1Z2, Canada
| | - Frank Wuest
- Department of Oncology, University of Alberta, 11560 University Ave., Edmonton, AB T6G 1Z2, Canada; (B.J.B.N.); (J.W.); (J.D.A.)
- Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, AB T6G 2E1, Canada
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20
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Franchi S, Asti M, Di Marco V, Tosato M. The Curies' element: state of the art and perspectives on the use of radium in nuclear medicine. EJNMMI Radiopharm Chem 2023; 8:38. [PMID: 37947909 PMCID: PMC10638329 DOI: 10.1186/s41181-023-00220-4] [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: 09/27/2023] [Accepted: 10/19/2023] [Indexed: 11/12/2023] Open
Abstract
BACKGROUND The alpha-emitter radium-223 (223Ra) is presently used in nuclear medicine for the palliative treatment of bone metastases from castration-resistant prostate cancer. This application arises from its advantageous decay properties and its intrinsic ability to accumulate in regions of high bone turnover when injected as a simple chloride salt. The commercial availability of [223Ra]RaCl2 as a registered drug (Xofigo®) is a further additional asset. MAIN BODY The prospect of extending the utility of 223Ra to targeted α-therapy of non-osseous cancers has garnered significant interest. Different methods, such as the use of bifunctional chelators and nanoparticles, have been explored to incorporate 223Ra in proper carriers designed to precisely target tumor sites. Nevertheless, the search for a suitable scaffold remains an ongoing challenge, impeding the diffusion of 223Ra-based radiopharmaceuticals. CONCLUSION This review offers a comprehensive overview of the current role of radium radioisotopes in nuclear medicine, with a specific focus on 223Ra. It also critically examines the endeavors conducted so far to develop constructs capable of incorporating 223Ra into cancer-targeting drugs. Particular emphasis is given to the chemical aspects aimed at providing molecular scaffolds for the bifunctional chelator approach.
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Affiliation(s)
- Sara Franchi
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131, Padua, Italy
| | - Mattia Asti
- Radiopharmaceutical Chemistry Section, Nuclear Medicine Unit, AUSL di Reggio Emilia: Azienda Unità Sanitaria Locale - IRCCS Tecnologie Avanzate e Modelli Assistenziali in Oncologia di Reggio Emilia, Via Amendola 2, 42122, Reggio Emilia, Italy
| | - Valerio Di Marco
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131, Padua, Italy
| | - Marianna Tosato
- Radiopharmaceutical Chemistry Section, Nuclear Medicine Unit, AUSL di Reggio Emilia: Azienda Unità Sanitaria Locale - IRCCS Tecnologie Avanzate e Modelli Assistenziali in Oncologia di Reggio Emilia, Via Amendola 2, 42122, Reggio Emilia, Italy.
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21
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McIntosh LA, Burns JD, Tereshatov EE, Muzzioli R, Hagel K, Jinadu NA, McCann LA, Picayo GA, Pisaneschi F, Piwnica-Worms D, Schultz SJ, Tabacaru GC, Abbott A, Green B, Hankins T, Hannaman A, Harvey B, Lofton K, Rider R, Sorensen M, Tabacaru A, Tobin Z, Yennello SJ. Production, isolation, and shipment of clinically relevant quantities of astatine-211: A simple and efficient approach to increasing supply. Nucl Med Biol 2023; 126-127:108387. [PMID: 37837782 DOI: 10.1016/j.nucmedbio.2023.108387] [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: 07/06/2023] [Revised: 09/04/2023] [Accepted: 09/18/2023] [Indexed: 10/16/2023]
Abstract
The alpha emitter astatine-211 (211At) is a promising candidate for cancer treatment based on Targeted Alpha (α) Therapy (TAT). A small number of facilities, distributed across the United States, are capable of accelerating α-particle beams to produce 211At. However, challenges remain regarding strategic methods for shipping 211At in a form adaptable to advanced radiochemistry reactions and other uses of the radioisotope. PURPOSE Our method allows shipment of 211At in various quantities in a form convenient for further radiochemistry. PROCEDURES For this study, a 3-octanone impregnated Amberchrom CG300M resin bed in a column cartridge was used to separate 211At from the bismuth matrix on site at the production accelerator (Texas A&M) in preparation for shipping. Aliquots of 6 M HNO3 containing up to ≈2.22 GBq of 211At from the dissolved target were successfully loaded and retained on columns. Exempt packages (<370 MBq) were shipped to a destination radiochemistry facility, University of Texas MD Anderson Cancer Center, in the form of a convenient air-dried column. Type A packages have been shipped overnight to University of Alabama at Birmingham. MAIN FINDINGS Air-dried column hold times of various lengths did not inhibit simple and efficient recovery of 211At. Solution eluted from the column was sufficiently high in specific activity to successfully radiolabel a model compound, 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)aniline (1), with 211At. The method to prepare and ship 211At described in this manuscript has also been used to ship larger quantities of 211At a greater distance to University of Alabama at Birmingham. PRINCIPAL CONCLUSIONS The successful proof of this method paves the way for the distribution of 211At from Texas A&M University to research institutions and clinical oncology centers in Texas and elsewhere. Use of this simple method at other facilities has the potential increase the overall availability of 211At for preclinical and clinical studies.
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Affiliation(s)
- Lauren A McIntosh
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA.
| | - Jonathan D Burns
- Chemistry Department, The University of Alabama at Birmingham, Birmingham, AL 35924, USA.
| | | | - Riccardo Muzzioli
- Department of Cancer System Imaging, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Kris Hagel
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA
| | - Noimat A Jinadu
- Chemistry Department, The University of Alabama at Birmingham, Birmingham, AL 35924, USA
| | - Laura A McCann
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA; Chemistry Department, Texas A&M University, College Station, TX 77843, USA
| | - Gabriela A Picayo
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA; Chemistry Department, Texas A&M University, College Station, TX 77843, USA
| | - Federica Pisaneschi
- Department of Cancer System Imaging, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Center for Translational Cancer Research, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases (IMM) at The University of Texas Health Science Center at Houston, USA
| | - David Piwnica-Worms
- Department of Cancer System Imaging, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Steven J Schultz
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA; Chemistry Department, Texas A&M University, College Station, TX 77843, USA
| | - Gabriel C Tabacaru
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA
| | - Austin Abbott
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA; Chemistry Department, Texas A&M University, College Station, TX 77843, USA
| | - Brooklyn Green
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA; Chemistry Department, Texas A&M University, College Station, TX 77843, USA
| | - Travis Hankins
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA; Chemistry Department, Texas A&M University, College Station, TX 77843, USA
| | - Andrew Hannaman
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA; Chemistry Department, Texas A&M University, College Station, TX 77843, USA
| | - Bryan Harvey
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA; Physics Department, Texas A&M University, College Station, TX 77843, USA
| | - Kylie Lofton
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA; Chemistry Department, Texas A&M University, College Station, TX 77843, USA
| | - Robert Rider
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA; Chemistry Department, Texas A&M University, College Station, TX 77843, USA
| | - Maxwell Sorensen
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA; Chemistry Department, Texas A&M University, College Station, TX 77843, USA
| | - Alexandra Tabacaru
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA
| | - Zachary Tobin
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA; Chemistry Department, Texas A&M University, College Station, TX 77843, USA
| | - Sherry J Yennello
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA; Chemistry Department, Texas A&M University, College Station, TX 77843, USA
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22
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Zimmermann R. Is Actinium Really Happening? J Nucl Med 2023; 64:1516-1518. [PMID: 37591546 DOI: 10.2967/jnumed.123.265907] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 07/25/2023] [Indexed: 08/19/2023] Open
Affiliation(s)
- Richard Zimmermann
- Chrysalium Consulting, Lalaye, France; MEDraysintell, Louvain-la-Neuve, Belgium; and Oncidium Foundation, Mont-Saint-Guibert, Belgium
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23
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Kostelnik TI, Olson AP, Grundmane A, Ellison PA, Mynerich J, Chen S, Marinova A, Randhawa P, Karaivanov D, Aluicio-Sarduy E, Barnhart TE, Orvig C, Ramogida CF, Hoehr C, Filosofov D, Engle JW, Radchenko V. Production and radiochemistry of antimony-120m: Efforts toward Auger electron therapy with 119Sb. Nucl Med Biol 2023; 122-123:108352. [PMID: 37390607 DOI: 10.1016/j.nucmedbio.2023.108352] [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: 02/02/2023] [Revised: 03/23/2023] [Accepted: 05/30/2023] [Indexed: 07/02/2023]
Abstract
Targeted Meitner-Auger Therapy (TMAT) has potential for personalized treatment thanks to its subcellular dosimetric selectivity, which is distinct from the dosimetry of β- and α particle emission based Targeted Radionuclide Therapy (TRT). To date, most clinical and preclinical TMAT studies have used commercially available radionuclides. These studies showed promising results despite using radionuclides with theoretically suboptimal photon to electron ratios, decay kinetics, and electron emission spectra. Studies using radionuclides whose decay characteristics are considered more optimal are therefore important for evaluation of the full potential of Meitner-Auger therapy; 119Sb is among the best such candidates. In the present work, we develop radiochemical purification of 120Sb from irradiated natural tin targets for TMAT studies with 119Sb.
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Affiliation(s)
- Thomas I Kostelnik
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - Aeli P Olson
- Department of Medical Physics, University of Wisconsin-Madison, Madison, WI 53705, United States
| | - Aivija Grundmane
- Department of Chemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Paul A Ellison
- Department of Medical Physics, University of Wisconsin-Madison, Madison, WI 53705, United States
| | - Jenasee Mynerich
- Faculty of Science, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada
| | - Shaohuang Chen
- Department of Chemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Atanaska Marinova
- Dzhelepov Laboratory of Nuclear Problems, Joint Institute for Nuclear Research, Dubna 141980, Russian Federation
| | - Parmissa Randhawa
- Department of Chemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Dimitar Karaivanov
- Dzhelepov Laboratory of Nuclear Problems, Joint Institute for Nuclear Research, Dubna 141980, Russian Federation
| | - Eduardo Aluicio-Sarduy
- Department of Medical Physics, University of Wisconsin-Madison, Madison, WI 53705, United States
| | - Todd E Barnhart
- Department of Medical Physics, University of Wisconsin-Madison, Madison, WI 53705, United States
| | - Chris Orvig
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | | | - Cornelia Hoehr
- Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada; Department of Computer Science, Mathematics, Physics, and Statistics, University of British Columbia Okanagan, Kelowna, British Columbia V1V 1V7, Canada
| | - Dmitry Filosofov
- Dzhelepov Laboratory of Nuclear Problems, Joint Institute for Nuclear Research, Dubna 141980, Russian Federation
| | - Jonathan W Engle
- Department of Medical Physics, University of Wisconsin-Madison, Madison, WI 53705, United States
| | - Valery Radchenko
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada.
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24
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Abou DS, Longtine M, Fears A, Benabdallah N, Unnerstall R, Johnston H, Shim K, Hasson A, Zhang H, Ulmert D, Mangin F, Ozen S, Raibaut L, Brandès S, Meyer M, Chambron JC, Tatum DS, Magda D, Wahl RL, Thorek DLJ. Evaluation of Candidate Theranostics for 227Th/ 89Zr Paired Radioimmunotherapy of Lymphoma. J Nucl Med 2023:jnumed.122.264979. [PMID: 37142300 DOI: 10.2967/jnumed.122.264979] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 03/07/2023] [Indexed: 05/06/2023] Open
Abstract
227Th is a promising radioisotope for targeted α-particle therapy. It produces 5 α-particles through its decay, with the clinically approved 223Ra as its first daughter. There is an ample supply of 227Th, allowing for clinical use; however, the chemical challenges of chelating this large tetravalent f-block cation are considerable. Using the CD20-targeting antibody ofatumumab, we evaluated chelation of 227Th4+ for α-particle-emitting and radiotheranostic applications. Methods: We compared 4 bifunctional chelators for thorium radiopharmaceutical preparation: S-2-(4-Isothiocyanatobenzyl)-1,4,7,10-tetraazacyclododecane tetraacetic acid (p-SCN-Bn-DOTA), 2-(4-isothicyanatobenzyl)-1,2,7,10,13-hexaazacyclooctadecane-1,4,7,10,13,16-hexaacetic acid (p-SCN-Bn-HEHA), p-isothiacyanatophenyl-1-hydroxy-2-oxopiperidine-desferrioxamine (DFOcyclo*-p-Phe-NCS), and macrocyclic 1,2-HOPO N-hydroxysuccinimide (L804-NHS). Immunoconstructs were evaluated for yield, purity, and stability in vitro and in vivo. Tumor targeting of the lead 227Th-labeled compound in vivo was performed in CD20-expressing models and compared with a companion 89Zr-labeled PET agent. Results: 227Th-labeled ofatumumab-chelator constructs were synthesized to a radiochemical purity of more than 95%, excepting HEHA. 227Th-HEHA-ofatumumab showed moderate in vitro stability. 227Th-DFOcyclo*-ofatumumab presented excellent 227Th labeling efficiency; however, high liver and spleen uptake was revealed in vivo, indicative of aggregation. 227Th-DOTA-ofatumumab labeled poorly, yielding no more than 5%, with low specific activity (0.08 GBq/g) and modest long-term in vitro stability (<80%). 227Th-L804-ofatumumab coordinated 227Th rapidly and efficiently at high yields, purity, and specific activity (8 GBq/g) and demonstrated extended stability. In vivo tumor targeting confirmed the utility of this chelator, and the diagnostic analog, 89Zr-L804-ofatumumab, showed organ distribution matching that of 227Th to delineate SU-DHL-6 tumors. Conclusion: Commercially available and novel chelators for 227Th showed a range of performances. The L804 chelator can be used with potent radiotheranostic capabilities for 89Zr/227Th quantitative imaging and α-particle therapy.
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Affiliation(s)
- Diane S Abou
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Mark Longtine
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Amanda Fears
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Nadia Benabdallah
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Ryan Unnerstall
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Hannah Johnston
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Kyuhwan Shim
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Abbie Hasson
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Hanwen Zhang
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - David Ulmert
- Department of Molecular and Medical Pharmacology, UCLA, Los Angeles, California
| | - Floriane Mangin
- Institut de Chimie de Strasbourg, UMR 7177, CNRS, Université de Strasbourg, Strasbourg, France
| | - Serife Ozen
- Institut de Chimie Moléculaire de l'Université de Bourgogne, UMR 6302, CNRS, Université de Bourgogne, Dijon, France
| | - Laurent Raibaut
- Institut de Chimie Moléculaire de l'Université de Bourgogne, UMR 6302, CNRS, Université de Bourgogne, Dijon, France
| | - Stéphane Brandès
- Institut de Chimie de Strasbourg, UMR 7177, CNRS, Université de Strasbourg, Strasbourg, France
| | - Michel Meyer
- Institut de Chimie de Strasbourg, UMR 7177, CNRS, Université de Strasbourg, Strasbourg, France
| | - Jean-Claude Chambron
- Institut de Chimie de Strasbourg, UMR 7177, CNRS, Université de Strasbourg, Strasbourg, France
| | | | | | - Richard L Wahl
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Daniel L J Thorek
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri;
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri; and
- Siteman Cancer Center, Oncologic Imaging Program, Alvin J. Siteman Cancer Center, Washington University School of Medicine, St. Louis, Missouri
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25
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Suryanarayana MV. Laser isotope separation of 223Ra. Sci Rep 2023; 13:7001. [PMID: 37117248 PMCID: PMC10147601 DOI: 10.1038/s41598-023-34204-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 04/25/2023] [Indexed: 04/30/2023] Open
Abstract
A three-step photoionization has been theoretically studied for the laser isotope separation of 223Ra through the following photoionization scheme. [Formula: see text] The effect of bandwidth, peak power density of the excitation and ionization lasers, Doppler broadening of the atomic ensemble, number density of the atoms, and charge exchange collisions on the laser isotope separation process has been studied. The optimum system parameters for the separation of 223Ra through this photoionization scheme have been derived. The effect of unknown parameters on the degree of enrichment has also been discussed. It has been theoretically shown that it is possible to produce 223Ra isotope with 98.5% radio-isotopic purity at a rate of 0.74 μg/h corresponding to the production rate of 435 patient doses per hour. This is the first ever study on the laser isotope separation of Radium isotopes.
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Affiliation(s)
- M V Suryanarayana
- Bhabha Atomic Research Centre, Visakhapatnam, Andhra Pradesh, India.
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26
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Ostuni E, Taylor MRG. Commercial and business aspects of alpha radioligand therapeutics. Front Med (Lausanne) 2023; 9:1070497. [PMID: 36816719 PMCID: PMC9932801 DOI: 10.3389/fmed.2022.1070497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 12/29/2022] [Indexed: 02/05/2023] Open
Abstract
Radioligand therapy (RLT) is gaining traction as a safe and effective targeted approach for the treatment of many cancer types, reflected by a substantial and growing commercial market (valued at $7.78 billion in 2021, with a projected value of $13.07 billion by 2030). Beta-emitting RLTs have a long history of clinical success dating back to the approval of Zevalin and Bexxar in the early 2000s, later followed by Lutathera and Pluvicto. Alpha radioligand therapeutics (ARTs) offer the potential for even greater success. Driven by ground-breaking clinical results in early trials, improved isotope availability, and better understanding of isotope and disease characteristics, the global market for alpha emitters was estimated at $672.3 million for the year 2020, with projected growth to $5.2 billion by 2027. New company formations, promising clinical trial data, and progression for many radioligand therapy products, as well as an inflow of investor capital, are contributing to this expanding field. Future growth will be fueled by further efficacy and safety data from ART clinical trials and real-world results, but challenges remain. Radionuclide supply, manufacturing, and distribution are key obstacles for growth of the field. New models of delivery are needed, along with cross-disciplinary training of specialized practitioners, to ensure patient access and avoid challenges faced by early RLT candidates such as Zevalin and Bexxar. Understanding of the history of radiation medicine is critical to inform what may be important to the success of ART-most past projections were inaccurate and it is important to analyze the reasons for this. Practical considerations in how radiation medicine is delivered and administered are important to understand in order to inform future approaches.
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Affiliation(s)
- Emanuele Ostuni
- ARTbio Inc., Cambridge, MA, United States,*Correspondence: Emanuele Ostuni,
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27
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Johnson JD, Heines M, Bruchertseifer F, Chevallay E, Cocolios TE, Dockx K, Duchemin C, Heinitz S, Heinke R, Hurier S, Lambert L, Leenders B, Skliarova H, Stora T, Wojtaczka W. Resonant laser ionization and mass separation of 225Ac. Sci Rep 2023; 13:1347. [PMID: 36693865 PMCID: PMC9873802 DOI: 10.1038/s41598-023-28299-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 01/17/2023] [Indexed: 01/25/2023] Open
Abstract
[Formula: see text]Ac is a radio-isotope that can be linked to biological vector molecules to treat certain distributed cancers using targeted alpha therapy. However, developing [Formula: see text]Ac-labelled radiopharmaceuticals remains a challenge due to the supply shortage of pure [Formula: see text]Ac itself. Several techniques to obtain pure [Formula: see text]Ac are being investigated, amongst which is the high-energy proton spallation of thorium or uranium combined with resonant laser ionization and mass separation. As a proof-of-principle, we perform off-line resonant ionization mass spectrometry on two samples of [Formula: see text]Ac, each with a known activity, in different chemical environments. We report overall operational collection efficiencies of 10.1(2)% and 9.9(8)% for the cases in which the [Formula: see text]Ac was deposited on a rhenium surface and a ThO[Formula: see text] mimic target matrix respectively. The bottleneck of the technique was the laser ionization efficiency, which was deduced to be 15.1(6)%.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Reinhard Heinke
- KU Leuven, IKS, 3000, Leuven, Belgium
- CERN, 1211, Geneva, Switzerland
| | - Sophie Hurier
- KU Leuven, IKS, 3000, Leuven, Belgium
- Belgian Nuclear Research Centre SCK CEN, Mol, Belgium
| | | | - Benji Leenders
- Belgian Nuclear Research Centre SCK CEN, Mol, Belgium
- Universiteit Gent, Gent, Belgium
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28
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Li RG, Stenberg VY, Larsen RH. An Experimental Generator for Production of High-Purity 212Pb for Use in Radiopharmaceuticals. J Nucl Med 2023; 64:173-176. [PMID: 35798556 PMCID: PMC9841245 DOI: 10.2967/jnumed.122.264009] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 06/22/2022] [Accepted: 06/22/2022] [Indexed: 01/28/2023] Open
Abstract
The feasibility, performance, and radiation safety of an experimental generator were evaluated to efficiently produce 212Pb intended for radiopharmaceuticals. Methods: The generator consisted of a flask with a removable cap containing a source of 224Ra or 228Th absorbed on quartz wool. Gaseous 220Rn emanated from the decaying source, which subsequently decayed to 212Pb, which was adsorbed on the flask's interior surface. The 212Pb was collected by washing the flask with 0.5-1 mL of 0.1 M HCl. Results: The generator collector flask trapped 62%-68% of the 212Pb, of which more than 87% (tested up to 26 MBq) could be harvested. The obtained 212Pb solution had a high purity (>99.98%) and could be used for the preparation of radioconjugates with more than 97% radiochemical purity. Future designs of the generator should aim to further reduce the risk of radon and γ-energy exposure to operators. Conclusion: The presented technology is a promising method for easy and convenient 212Pb production.
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Affiliation(s)
- Ruth Gong Li
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway; .,Department of Radiation Biology, Institute of Cancer Research, Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway.,Oncoinvent AS, Oslo, Norway
| | - Vilde Yuli Stenberg
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway;,Department of Radiation Biology, Institute of Cancer Research, Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway;,ArtBio AS, Oslo, Norway; and
| | - Roy Hartvig Larsen
- Oncoinvent AS, Oslo, Norway;,ArtBio AS, Oslo, Norway; and,Sciencons AS, Oslo, Norway
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29
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Herrmann K, Giovanella L, Santos A, Gear J, Ozgen Kiratli P, Kurth J, Denis-Bacelar AM, Hustinx R, Patt M, Wahl RL, Paez D, Giammarile F, Jadvar H, Pandit-Taskar N, Ghesani M, Kunikowska J. Joint EANM, SNMMI, and IAEA Enabling Guide: How to Set up a Theranostics Center. J Nucl Med 2022; 63:1836-1843. [PMID: 35450957 DOI: 10.2967/jnumed.122.264321] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 04/20/2022] [Indexed: 01/14/2023] Open
Abstract
The theranostics concept using the same target for both imaging and therapy dates back to the middle of the last century, when radioactive iodine was first used to treat thyroid diseases. Since then, radioiodine has become broadly established clinically for diagnostic imaging and therapy of benign and malignant thyroid disease, worldwide. However, only since the approval of SSTR2-targeting theranostics following the NETTER-1 trial in neuroendocrine tumors, and the positive outcome of the VISION trial has theranostics gained substantial attention beyond nuclear medicine. The roll-out of radioligand therapy for treating a high-incidence tumor such as prostate cancer requires the expansion of existing and the establishment of new theranostics centers. Despite wide global variation in the regulatory, financial and medical landscapes, this guide attempts to provide valuable information to enable interested stakeholders to safely initiate and operate theranostic centers. This enabling guide does not intend to answer all possible questions, but rather to serve as an overarching framework for multiple, more detailed future initiatives. It recognizes that there are regional differences in the specifics of regulation of radiation safety, but common elements of best practice valid globally.
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Affiliation(s)
- Ken Herrmann
- Department of Nuclear Medicine, University of Duisburg-Essen, Duisburg, Germany; .,German Cancer Consortium (DKTK)-University Hospital Essen, Essen, Germany
| | - Luca Giovanella
- Clinic for Nuclear Medicine and Molecular Imaging, Imaging Institute of Southern Switzerland, Ente Ospedaliero Cantonale, Bellinzona, Switzerland
| | - Andrea Santos
- Department of Nuclear Medicine, Hospital Cuf Descobertas, Lisbon, Portugal
| | - Jonathan Gear
- Joint Department of Physics, Royal Marsden NHS Foundation Trust, Sutton, Sutton, United Kingdom
| | | | - Jens Kurth
- Department of Nuclear Medicine, Rostock University Medical Center, Rostock, Germany
| | | | - Roland Hustinx
- Division of Nuclear Medicine and Oncological Imaging, University Hospital of Liège, Liège, Belgium.,GIGA-CRC in vivo imaging, University of Liège, Liège, Belgium
| | - Marianne Patt
- Department for Nuclear Medicine, University Hospital Leipzig, Leipzig, Germany
| | - Richard L Wahl
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Diana Paez
- Nuclear Medicine and Diagnostic Imaging Section, Division of Human Health, Department of Nuclear Sciences and Application, International Atomic Energy Agency, Vienna, Austria
| | - Francesco Giammarile
- Nuclear Medicine and Diagnostic Imaging Section, Division of Human Health, Department of Nuclear Sciences and Application, International Atomic Energy Agency, Vienna, Austria
| | - Hossein Jadvar
- Division of Nuclear Medicine, Department of Radiology, University of Southern California, Los Angeles, California
| | - Neeta Pandit-Taskar
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Munir Ghesani
- Diagnostic, Molecular & Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York, New York; and
| | - Jolanta Kunikowska
- Nuclear Medicine Department, Medical University of Warsaw, Warsaw, Poland
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30
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Bergeron DE, Cessna JT, Fitzgerald RP, Laureano-Pérez L, Pibida L, Zimmerman BE. Primary standardization of 212Pb activity by liquid scintillation counting. Appl Radiat Isot 2022; 190:110473. [PMID: 36201936 PMCID: PMC9827475 DOI: 10.1016/j.apradiso.2022.110473] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 09/16/2022] [Accepted: 09/16/2022] [Indexed: 01/11/2023]
Abstract
An activity standard for 212Pb in equilibrium with its progeny was realized, based on triple-to-double coincidence ratio (TDCR) liquid scintillation (LS) counting. A Monte Carlo-based approach to estimating uncertainties due to nuclear decay data (branching ratios, beta endpoint energies, γ-ray energies, and conversion coefficients for 212Pb and 208Tl) led to combined standard uncertainties ≤ 0.20 %. Confirmatory primary measurements were made by LS efficiency tracing with tritium and 4παβ(LS)-γ(NaI(Tl)) anticoincidence counting. The standard is discussed in relation to current approaches to 212Pb activity calibration. In particular, potential biases encountered when using inappropriate radionuclide calibrator settings are discussed.
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Affiliation(s)
- Denis E Bergeron
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA.
| | - Jeffrey T Cessna
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - Ryan P Fitzgerald
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - Lizbeth Laureano-Pérez
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - Leticia Pibida
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - Brian E Zimmerman
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
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31
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Marengo M, Infantino A. Assessment of emission data and transmission factors supporting radiation protection in the use of 225Ac. Phys Med 2022; 103:59-65. [DOI: 10.1016/j.ejmp.2022.10.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 10/03/2022] [Accepted: 10/07/2022] [Indexed: 11/29/2022] Open
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Franchi S, Di Marco V, Tosato M. Bismuth chelation for targeted alpha therapy: Current state of the art. Nucl Med Biol 2022; 114-115:168-188. [PMID: 35753940 DOI: 10.1016/j.nucmedbio.2022.06.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 05/22/2022] [Accepted: 06/14/2022] [Indexed: 12/27/2022]
Abstract
Current interest in the α-emitting bismuth radionuclides, bismuth-212 (212Bi) and bismuth-213 (213Bi), stems from their great potential for targeted alpha therapy (TAT), an expanding and promising approach for the treatment of micrometastatic disease and the eradication of single malignant cells. To selectively deliver their emission to the cancer cells, these radiometals must be firmly coordinated by a bifunctional chelator (BFC) attached to a tumour-seeking vector. This review provides a comprehensive overview of the current state-of-the-art chelating agents for bismuth radioisotopes. Several aspects are reported, from their 'cold' chelation chemistry (thermodynamic, kinetic, and structural properties) and radiolabelling investigations to the preclinical and clinical studies performed with a variety of bioconjugates. The aim of this review is to provide both a guide for the rational design of novel optimal platforms for the chelation of these attractive α-emitters and emphasize the prospects of the most encouraging chelating agents proposed so far.
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Affiliation(s)
- Sara Franchi
- Department of Chemical Sciences, University of Padova, 35131 Padova, Italy
| | - Valerio Di Marco
- Department of Chemical Sciences, University of Padova, 35131 Padova, Italy
| | - Marianna Tosato
- Department of Chemical Sciences, University of Padova, 35131 Padova, Italy.
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Efficient Production of the PET Radionuclide 133La for Theranostic Purposes in Targeted Alpha Therapy Using the 134Ba(p,2n) 133La Reaction. Pharmaceuticals (Basel) 2022; 15:ph15101167. [PMID: 36297279 PMCID: PMC9611457 DOI: 10.3390/ph15101167] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 09/15/2022] [Accepted: 09/16/2022] [Indexed: 01/18/2023] Open
Abstract
Targeted Alpha Therapy is a research field of highest interest in specialized radionuclide therapy. Over the last decades, several alpha-emitting radionuclides have entered and left research topics towards their clinical translation. Especially, 225Ac provides all necessary physical and chemical properties for a successful clinical application, which has already been shown by [225Ac]Ac-PSMA-617. While PSMA-617 carries the DOTA moiety as the complexing agent, the chelator macropa as a macrocyclic alternative provides even more beneficial properties regarding labeling and complex stability in vivo. Lanthanum-133 is an excellent positron-emitting diagnostic lanthanide to radiolabel macropa-functionalized therapeutics since 133La forms a perfectly matched theranostic pair of radionuclides with the therapeutic radionuclide 225Ac, which itself can optimally be complexed by macropa as well. 133La was thus produced by cyclotron-based proton irradiation of an enriched 134Ba target. The target (30 mg of [134Ba]BaCO3) was irradiated for 60 min at 22 MeV and 10−15 µA beam current. Irradiation side products in the raw target solution were identified and quantified: 135La (0.4%), 135mBa (0.03%), 133mBa (0.01%), and 133Ba (0.0004%). The subsequent workup and anion-exchange-based product purification process took approx. 30 min and led to a total amount of (1.2−1.8) GBq (decay-corrected to end of bombardment) of 133La, formulated as [133La]LaCl3. After the complete decay of 133La, a remainder of ca. 4 kBq of long-lived 133Ba per 100 MBq of 133La was detected and rated as uncritical regarding personal dose and waste management. Subsequent radiolabeling was successfully performed with previously published macropa-derived PSMA inhibitors at a micromolar range (quantitative labeling at 1 µM) and evaluated by radio-TLC and radio-HPLC analyses. The scale-up to radioactivity amounts that are needed for clinical application purposes would be easy to achieve by increasing target mass, beam current, and irradiation time to produce 133La of high radionuclide purity (>99.5%) regarding labeling properties and side products.
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Oxidation of p-[125I]Iodobenzoic Acid and p-[211At]Astatobenzoic Acid Derivatives and Evaluation In Vivo. Int J Mol Sci 2022; 23:ijms231810655. [PMID: 36142567 PMCID: PMC9506049 DOI: 10.3390/ijms231810655] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 08/17/2022] [Accepted: 08/24/2022] [Indexed: 11/23/2022] Open
Abstract
The alpha particle-emitting radionuclide astatine-211 (211At) is of interest for targeted radiotherapy; however, low in vivo stability of many 211At-labeled cancer-targeting molecules has limited its potential. As an alternative labeling method, we evaluated whether a specific type of astatinated aryl compound that has the At atom in a higher oxidation state might be stable to in vivo deastatination. In the research effort, para-iodobenzoic acid methyl ester and dPEG4-amino acid methyl ester derivatives were prepared as HPLC standards. The corresponding para-stannylbenzoic acid derivatives were also prepared and labeled with 125I and 211At. Oxidization of the [125I]iodo- and [211At]astato-benzamidyl-dPEG4-acid methyl ester derivatives provided materials for in vivo evaluation. A biodistribution was conducted in mice with coinjected oxidized 125I- and 211At-labeled compounds. The oxidized radioiodinated derivative was stable to in vivo deiodination, but unfortunately the oxidized [211At]astatinated benzamide derivative was found to be unstable under the conditions of isolation by radio-HPLC (post animal injection). Another biodistribution study in mice evaluated the tissue concentrations of coinjected [211At]NaAtO3 and [125I]NaIO3. Comparison of the tissue concentrations of the isolated material from the oxidized [211At]benzamide derivative with those of [211At]astatate indicated the species obtained after isolation was likely [211At]astatate.
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Augusto R, Smith J, Varah S, Paley W, Egoriti L, McEwen S, Goodacre TD, Mildenberger J, Gottberg A, Trudel A, Hoehr C. Design and radiological study of the 225Ac medical target at the TRIUMF-ARIEL proton-target station. Radiat Phys Chem Oxf Engl 1993 2022. [DOI: 10.1016/j.radphyschem.2022.110491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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36
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Separation of radium and actinium using zirconia. Appl Radiat Isot 2022; 185:110238. [DOI: 10.1016/j.apradiso.2022.110238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/04/2022] [Accepted: 04/07/2022] [Indexed: 11/23/2022]
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37
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Research and Development for Cyclotron Production of 225Ac from 226Ra—The Challenges in a Country Lacking Natural Resources for Medical Applications. Processes (Basel) 2022. [DOI: 10.3390/pr10061215] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The high therapeutic effect of targeted radioisotope/radionuclide therapy (TRT) using α-emitters, especially 225Ac, is attracting attention worldwide. However, the only 225Ac production method that has been put into practical use is extraction from a 229Th generator derived from the nuclear fuel 233U, and it is unlikely that this method alone is able to meet future global medical demand. Development towards new 225Ac production methods is in progress. These new 225Ac production methods require the irradiation of 232Th or 226Ra using an accelerator or a nuclear reactor. Global competition has already begun in the race to secure a reliable supply of 232Th and 226Ra, as well as 229Th for the conventional production method. Japan is a “resource-poor country” that depends on foreign countries for most of its needs. As such, it is difficult for Japan to secure raw materials such as 232Th and 226Ra for medical application. In this paper, we look back on our research at the National Institutes for Quantum Science and Technology (QST) in the fields of 225Ac production and 225Ac-labeled pharmaceutical development. We present the history and details of our research from 2011, as well as the development of a collaboration between QST and Nihon Medi-Physics that focuses on research into 225Ac production via 226Ra(p,2n)225Ac reaction using an accelerator. Furthermore, we review the valuable discussion at the 2018 Joint IAEA-JRC Workshop—“Supply of Actinium-225”, an international conference that we participated in. Overall, the statuses of external 225Ac supply, domestic production, and distribution are discussed, as are the latest developments in 225Ac production methods, 225Ac pharmaceuticals, and future prospects for the domestic production of 225Ac in Japan, a country lacking natural resources for medical applications.
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An alternative radiochemical separation strategy for isolation of Ac and Ra isotopes from high energy proton irradiated thorium targets for further application in Targeted Alpha Therapy (TAT). Nucl Med Biol 2022; 112-113:35-43. [DOI: 10.1016/j.nucmedbio.2022.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 06/10/2022] [Accepted: 06/14/2022] [Indexed: 11/21/2022]
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China’s radiopharmaceuticals on expressway: 2014–2021. RADIOCHIM ACTA 2022. [DOI: 10.1515/ract-2021-1137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
This review provides an essential overview on the progress of rapidly-developing China’s radiopharmaceuticals in recent years (2014–2021). Our discussion reflects on efforts to develop potential, preclinical, and in-clinical radiopharmaceuticals including the following areas: (1) brain imaging agents, (2) cardiovascular imaging agents, (3) infection and inflammation imaging agents, (4) tumor radiopharmaceuticals, and (5) boron delivery agents (a class of radiopharmaceutical prodrug) for neutron capture therapy. Especially, the progress in basic research, including new radiolabeling methodology, is highlighted from a standpoint of radiopharmaceutical chemistry. Meanwhile, we briefly reflect on the recent major events related to radiopharmaceuticals along with the distribution of major R&D forces (universities, institutions, facilities, and companies), clinical study status, and national regulatory supports. We conclude with a brief commentary on remaining limitations and emerging opportunities for China’s radiopharmaceuticals.
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40
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Gafita A, Marcus C, Kostos L, Schuster DM, Calais J, Hofman MS. Predictors and Real-World Use of Prostate-Specific Radioligand Therapy: PSMA and Beyond. Am Soc Clin Oncol Educ Book 2022; 42:1-17. [PMID: 35609224 DOI: 10.1200/edbk_350946] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
PSMA is a transmembrane protein that is markedly overexpressed in prostate cancer, making it an excellent target for imaging and treating patients with prostate cancer. Several small molecule inhibitors and antibodies of PSMA have been radiolabeled for use as therapeutic agents and are currently under clinical investigation. PSMA-based radionuclide therapy is a promising therapeutic option for men with metastatic prostate cancer. The phase II TheraP study demonstrated superior efficacy, lower side effects, and improved patient-reported outcomes compared with cabazitaxel. The phase III VISION study demonstrated that radionuclide therapy with β-emitter 177Lu-PSMA-617 can prolong survival and improve quality of life when offered in addition to standard-of-care therapy in men with PSMA-positive metastatic castration-resistant prostate cancer whose disease had progressed with conventional treatments. Nevertheless, up to 30% of patients have inherent resistance to PSMA-based radionuclide therapy, and acquired resistance is inevitable. Hence, strategies to increase the efficacy of PSMA-based radionuclide therapy have been under clinical investigation. These include better patient selection; increased radiation damage delivery via dosimetry-based administered dose or use of α-emitters instead of β-emitters; or using combinatorial approaches to overcome radioresistance mechanisms (innate or acquired), such as with novel hormonal agents, PARP inhibitors, or immunotherapy.
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Affiliation(s)
- Andrei Gafita
- Ahmanson Translational Imaging Division, Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA
| | - Charles Marcus
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA
| | - Louise Kostos
- Medical Oncology, Peter MacCallum Cancer Centre, Melbourne, Australia
| | - David M Schuster
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA
| | - Jeremie Calais
- Ahmanson Translational Imaging Division, Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA
| | - Michael S Hofman
- Molecular Imaging and Therapeutic Nuclear Medicine, Cancer Imaging; Prostate Cancer Theranostics and Imaging Centre of Excellence, Peter MacCallum Cancer Centre, Melbourne, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Australia
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41
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Design, synthesis, and preclinical evaluation of a novel bifunctional macrocyclic chelator for theranostics of cancers. Eur J Nucl Med Mol Imaging 2022; 49:2618-2633. [DOI: 10.1007/s00259-022-05750-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 03/01/2022] [Indexed: 12/22/2022]
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42
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Separation, speciation, and mechanism of astatine and bismuth extraction from nitric acid into 1-octanol and methyl anthranilate. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2021.120088] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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43
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Hu A, Brown V, MacMillan SN, Radchenko V, Yang H, Wharton L, Ramogida CF, Wilson JJ. Chelating the Alpha Therapy Radionuclides 225Ac 3+ and 213Bi 3+ with 18-Membered Macrocyclic Ligands Macrodipa and Py-Macrodipa. Inorg Chem 2022; 61:801-806. [PMID: 34965102 PMCID: PMC9372718 DOI: 10.1021/acs.inorgchem.1c03670] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The radionuclides 225Ac3+ and 213Bi3+ possess favorable physical properties for targeted alpha therapy (TAT), a therapeutic approach that leverages α radiation to treat cancers. A chelator that effectively binds and retains these radionuclides is required for this application. The development of ligands for this purpose, however, is challenging because the large ionic radii and charge-diffuse nature of these metal ions give rise to weaker metal-ligand interactions. In this study, we evaluated two 18-membered macrocyclic chelators, macrodipa and py-macrodipa, for their ability to complex 225Ac3+ and 213Bi3+. Their coordination chemistry with Ac3+ was probed computationally and with Bi3+ experimentally via NMR spectroscopy and X-ray crystallography. Furthermore, radiolabeling studies were conducted, revealing the efficient incorporation of both 225Ac3+ and 213Bi3+ by py-macrodipa that matches or surpasses the well-known chelators macropa and DOTA. Incubation in human serum at 37 °C showed that ∼90% of the 225Ac3+-py-macrodipa complex dissociates after 1 d. The Bi3+-py-macrodipa complex possesses remarkable kinetic inertness reflected by an EDTA transchelation challenge study, surpassing that of Bi3+-macropa. This work establishes py-macrodipa as a valuable candidate for 213Bi3+ TAT, providing further motivation for its implementation within new radiopharmaceutical agents.
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Affiliation(s)
- Aohan Hu
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Victoria Brown
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Samantha N. MacMillan
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Valery Radchenko
- Life Sciences Division, TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Hua Yang
- Life Sciences Division, TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - Luke Wharton
- Life Sciences Division, TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Caterina F. Ramogida
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
- Life Sciences Division, TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - Justin J. Wilson
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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Joint EANM, SNMMI and IAEA enabling guide: how to set up a theranostics centre. Eur J Nucl Med Mol Imaging 2022; 49:2300-2309. [PMID: 35403861 PMCID: PMC9165261 DOI: 10.1007/s00259-022-05785-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 03/25/2022] [Indexed: 01/14/2023]
Abstract
The theranostics concept using the same target for both imaging and therapy dates back to the middle of the last century, when radioactive iodine was first used to treat thyroid diseases. Since then, radioiodine has become broadly established clinically for diagnostic imaging and therapy of benign and malignant thyroid disease, worldwide. However, only since the approval of SSTR2-targeting theranostics following the NETTER-1 trial in neuroendocrine tumours and the positive outcome of the VISION trial has theranostics gained substantial attention beyond nuclear medicine. The roll-out of radioligand therapy for treating a high-incidence tumour such as prostate cancer requires the expansion of existing and the establishment of new theranostics centres. Despite wide global variation in the regulatory, financial and medical landscapes, this guide attempts to provide valuable information to enable interested stakeholders to safely initiate and operate theranostics centres. This enabling guide does not intend to answer all possible questions, but rather to serve as an overarching framework for multiple, more detailed future initiatives. It recognizes that there are regional differences in the specifics of regulation of radiation safety, but common elements of best practice valid globally.
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45
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Neels OC, Kopka K, Liolios C, Afshar-Oromieh A. Radiolabeled PSMA Inhibitors. Cancers (Basel) 2021; 13:6255. [PMID: 34944875 PMCID: PMC8699044 DOI: 10.3390/cancers13246255] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 12/10/2021] [Accepted: 12/11/2021] [Indexed: 12/16/2022] Open
Abstract
PSMA has shown to be a promising target for diagnosis and therapy (theranostics) of prostate cancer. We have reviewed developments in the field of radio- and fluorescence-guided surgery and targeted photodynamic therapy as well as multitargeting PSMA inhibitors also addressing albumin, GRPr and integrin αvβ3. An overview of the regulatory status of PSMA-targeting radiopharmaceuticals in the USA and Europe is also provided. Technical and quality aspects of PSMA-targeting radiopharmaceuticals are described and new emerging radiolabeling strategies are discussed. Furthermore, insights are given into the production, application and potential of alternatives beyond the commonly used radionuclides for radiolabeling PSMA inhibitors. An additional refinement of radiopharmaceuticals is required in order to further improve dose-limiting factors, such as nephrotoxicity and salivary gland uptake during endoradiotherapy. The improvement of patient treatment achieved by the advantageous combination of radionuclide therapy with alternative therapies is also a special focus of this review.
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Affiliation(s)
- Oliver C. Neels
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstrasse 400, 01328 Dresden, Germany;
| | - Klaus Kopka
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstrasse 400, 01328 Dresden, Germany;
- Faculty of Chemistry and Food Chemistry, School of Science, Technical University Dresden, Mommsenstrasse 4, 01062 Dresden, Germany
| | - Christos Liolios
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, National & Kapodistrian University of Athens, Zografou, 15771 Athens, Greece;
- INRASTES, Radiochemistry Laboratory, NCSR “Demokritos”, Ag. Paraskevi Attikis, 15310 Athens, Greece
| | - Ali Afshar-Oromieh
- Department of Nuclear Medicine, Bern University Hospital (Inselspital), Freiburgstrasse 18, 3010 Bern, Switzerland;
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46
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A Novel Single-Step-Labeled 212Pb-CaCO 3 Microparticle for Internal Alpha Therapy: Preparation, Stability, and Preclinical Data from Mice. MATERIALS 2021; 14:ma14237130. [PMID: 34885283 PMCID: PMC8658347 DOI: 10.3390/ma14237130] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/19/2021] [Accepted: 11/19/2021] [Indexed: 02/06/2023]
Abstract
Lead-212 is recognized as a promising radionuclide for targeted alpha therapy for tumors. Many studies of 212Pb-labeling of various biomolecules through bifunctional chelators have been conducted. Another approach to exploiting the cytotoxic effect is coupling the radionuclide to a microparticle acting as a carrier vehicle, which could be used for treating disseminated cancers in body cavities. Calcium carbonate may represent a suitable material, as it is biocompatible, biodegradable, and easy to synthesize. In this work, we explored 212Pb-labeling of various CaCO3 microparticles and developed a protocol that can be straightforwardly implemented by clinicians. Vaterite microparticles stabilized by pamidronate were effective as 212Pb carriers; labeling yields of ≥98% were achieved, and 212Pb was strongly retained by the particles in an in vitro stability assessment. Moreover, the amounts of 212Pb reaching the kidneys, liver, spleen, and skeleton of mice following intraperitoneal (i.p.) administration were very low compared to i.p. injection of unbound 212Pb2+, indicating that CaCO3-bound 212Pb exhibited stability when administered intraperitoneally. Therapeutic efficacy was observed in a model of i.p. ovarian cancer for all the tested doses, ranging from 63 to 430 kBq per mouse. Lead-212-labeled CaCO3 microparticles represent a promising candidate for treating intracavitary cancers.
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47
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Hydroxypyridinones as a Very Promising Platform for Targeted Diagnostic and Therapeutic Radiopharmaceuticals. Molecules 2021. [DOI: 10.3390/molecules26226997
expr 973886017 + 973118332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Hydroxypyridinones (HOPOs) have been used in the chelation therapy of iron and actinide metals. Their application in metal-based radiopharmaceuticals has also been increasing in recent years. This review article focuses on how multidentate HOPOs can be used in targeted radiometal-based diagnostic and therapeutic radiopharmaceuticals. The general structure of radiometal-based targeted radiopharmaceuticals, a brief description of siderophores, the basic structure and properties of bidentate HOPO, some representative HOPO multidentate chelating agents, radiopharmaceuticals based on HOPO multidentate bifunctional chelators for gallium-68, thorium-227 and zirconium-89, as well as the future prospects of HOPO multidentate bifunctional chelators in other metal-based radiopharmaceuticals are described and discussed in turn. The HOPO metal-based radiopharmaceuticals that have shown good prospects in clinical and preclinical studies are gallium-68, thorium-227 and zirconium-89 radiopharmaceuticals. We expect HOPO multidentate bifunctional chelators to be a very promising platform for building novel targeted radiometal-based diagnostic and therapeutic radiopharmaceuticals.
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48
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Zhou X, Dong L, Shen L. Hydroxypyridinones as a Very Promising Platform for Targeted Diagnostic and Therapeutic Radiopharmaceuticals. Molecules 2021; 26:6997. [PMID: 34834087 PMCID: PMC8619595 DOI: 10.3390/molecules26226997&set/a 916769719+956065658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Hydroxypyridinones (HOPOs) have been used in the chelation therapy of iron and actinide metals. Their application in metal-based radiopharmaceuticals has also been increasing in recent years. This review article focuses on how multidentate HOPOs can be used in targeted radiometal-based diagnostic and therapeutic radiopharmaceuticals. The general structure of radiometal-based targeted radiopharmaceuticals, a brief description of siderophores, the basic structure and properties of bidentate HOPO, some representative HOPO multidentate chelating agents, radiopharmaceuticals based on HOPO multidentate bifunctional chelators for gallium-68, thorium-227 and zirconium-89, as well as the future prospects of HOPO multidentate bifunctional chelators in other metal-based radiopharmaceuticals are described and discussed in turn. The HOPO metal-based radiopharmaceuticals that have shown good prospects in clinical and preclinical studies are gallium-68, thorium-227 and zirconium-89 radiopharmaceuticals. We expect HOPO multidentate bifunctional chelators to be a very promising platform for building novel targeted radiometal-based diagnostic and therapeutic radiopharmaceuticals.
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Affiliation(s)
- Xu Zhou
- HTA Co., Ltd., Beijing 102413, China;
- China Isotope & Radiation Corporation, Beijing 100089, China;
| | - Linlin Dong
- China Isotope & Radiation Corporation, Beijing 100089, China;
| | - Langtao Shen
- HTA Co., Ltd., Beijing 102413, China;
- China Isotope & Radiation Corporation, Beijing 100089, China;
- National Isotope Center of Engineering and Technology, China Institute of Atomic Energy, Beijing 102413, China
- Correspondence:
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49
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Zhou X, Dong L, Shen L. Hydroxypyridinones as a Very Promising Platform for Targeted Diagnostic and Therapeutic Radiopharmaceuticals. Molecules 2021; 26:6997. [PMID: 34834087 PMCID: PMC8619595 DOI: 10.3390/molecules26226997] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 11/13/2021] [Accepted: 11/17/2021] [Indexed: 01/30/2023] Open
Abstract
Hydroxypyridinones (HOPOs) have been used in the chelation therapy of iron and actinide metals. Their application in metal-based radiopharmaceuticals has also been increasing in recent years. This review article focuses on how multidentate HOPOs can be used in targeted radiometal-based diagnostic and therapeutic radiopharmaceuticals. The general structure of radiometal-based targeted radiopharmaceuticals, a brief description of siderophores, the basic structure and properties of bidentate HOPO, some representative HOPO multidentate chelating agents, radiopharmaceuticals based on HOPO multidentate bifunctional chelators for gallium-68, thorium-227 and zirconium-89, as well as the future prospects of HOPO multidentate bifunctional chelators in other metal-based radiopharmaceuticals are described and discussed in turn. The HOPO metal-based radiopharmaceuticals that have shown good prospects in clinical and preclinical studies are gallium-68, thorium-227 and zirconium-89 radiopharmaceuticals. We expect HOPO multidentate bifunctional chelators to be a very promising platform for building novel targeted radiometal-based diagnostic and therapeutic radiopharmaceuticals.
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Affiliation(s)
- Xu Zhou
- HTA Co., Ltd., Beijing 102413, China;
- China Isotope & Radiation Corporation, Beijing 100089, China;
| | - Linlin Dong
- China Isotope & Radiation Corporation, Beijing 100089, China;
| | - Langtao Shen
- HTA Co., Ltd., Beijing 102413, China;
- China Isotope & Radiation Corporation, Beijing 100089, China;
- National Isotope Center of Engineering and Technology, China Institute of Atomic Energy, Beijing 102413, China
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