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Kaur T, Brooks AF, Liddell KM, Henderson BD, Hockley BG, Bohnen NI, Albin RL, Scott PJH. Automated Synthesis of 18F-BCPP-EF {2- tert-Butyl-4-Chloro-5-{6-[2-(2[ 18F]fluoroethoxy)-Ethoxy]-Pyridin-3-ylmethoxy}-2 H-Pyridazin-3-One for Imaging of Mitochondrial Complex 1 in Parkinson's Disease. Front Chem 2022; 10:878835. [PMID: 35433631 PMCID: PMC9005973 DOI: 10.3389/fchem.2022.878835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 03/14/2022] [Indexed: 11/06/2022] Open
Abstract
Mitochondrial complex I (MC-I) is an essential component of brain bioenergetics and can be quantified and studied using positron emission tomography (PET). A specific high affinity 18F radiotracer for MC-I enables monitoring of neurodegenerative disease progression and pathology via PET imaging. To facilitate clinical research studies tracking MC-I activity in Parkinson's disease and other neurodegenerative diseases, a fully automated synthesis of the recently described 2-tert-butyl-4-chloro-5-{6-[2-(2[18F]fluoroethoxy)-ethoxy]-pyridin-3-ylmethoxy}-2H-pyridazin-3-one ([18F] BCPP-EF, [ 18 F]1) was developed. We report the first automated synthesis [18F]BCPP-EF using a green radiochemistry approach. The radiotracer was synthesized with good radiochemical yield, excellent radiochemical purity, and high molar activity.
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Affiliation(s)
- Tanpreet Kaur
- Department of Radiology, The University of Michigan Medical School, Ann Arbor, MI, United States
| | - Allen F. Brooks
- Department of Radiology, The University of Michigan Medical School, Ann Arbor, MI, United States
| | - Katherine M. Liddell
- Department of Radiology, The University of Michigan Medical School, Ann Arbor, MI, United States
| | - Bradford D. Henderson
- Department of Radiology, The University of Michigan Medical School, Ann Arbor, MI, United States
| | - Brian G. Hockley
- Department of Radiology, The University of Michigan Medical School, Ann Arbor, MI, United States
| | - Nicolaas I. Bohnen
- Department of Radiology, The University of Michigan Medical School, Ann Arbor, MI, United States,Department of Neurology, University of Michigan, Ann Arbor, MI, United States,Neurology Service and Geriatrics Research, Education, and Clinical Center, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, MI, United States,University of Michigan Udall Center of Excellence for Parkinson’s Disease Research, Ann Arbor, MI, United States
| | - Roger L. Albin
- Department of Neurology, University of Michigan, Ann Arbor, MI, United States,Neurology Service and Geriatrics Research, Education, and Clinical Center, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, MI, United States,University of Michigan Udall Center of Excellence for Parkinson’s Disease Research, Ann Arbor, MI, United States
| | - Peter J. H. Scott
- Department of Radiology, The University of Michigan Medical School, Ann Arbor, MI, United States,*Correspondence: Peter J. H. Scott,
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Rodnick ME, Sollert C, Stark D, Clark M, Katsifis A, Hockley BG, Parr DC, Frigell J, Henderson BD, Bruton L, Preshlock S, Abghari-Gerst M, Piert MR, Fulham MJ, Eberl S, Gagnon K, Scott PJH. Synthesis of 68Ga-radiopharmaceuticals using both generator-derived and cyclotron-produced 68Ga as exemplified by [ 68Ga]Ga-PSMA-11 for prostate cancer PET imaging. Nat Protoc 2022; 17:980-1003. [PMID: 35246649 DOI: 10.1038/s41596-021-00662-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 10/25/2021] [Indexed: 11/09/2022]
Abstract
[68Ga]Ga-PSMA-11, a urea-based peptidomimetic, is a diagnostic radiopharmaceutical for positron emission tomography (PET) imaging that targets the prostate-specific membrane antigen (PSMA). The recent Food and Drug Administration approval of [68Ga]Ga-PSMA-11 for PET imaging of patients with prostate cancer, expected follow-up approval of companion radiotherapeutics (e.g., [177Lu]Lu-PSMA-617, [225Ac]Ac-PSMA-617) and large prostate cancer patient volumes requiring access are poised to create an unprecedented demand for [68Ga]Ga-PSMA-11 in nuclear medicine clinics around the world. Meeting this global demand is going to require a variety of synthesis methods compatible with 68Ga eluted from a generator or produced on a cyclotron. To address this urgent need in the PET radiochemistry community, herein we report detailed protocols for the synthesis of [68Ga]Ga-PSMA-11, (also known as HBED-CC, Glu-urea-Lys(Ahx)-HBED-CC and PSMA-HBED-CC) using both generator-eluted and cyclotron-produced 68Ga and contrast the pros and cons of each method. The radiosyntheses are automated and have been validated for human use at two sites (University of Michigan (UM), United States; Royal Prince Alfred Hospital (RPA), Australia) and used to produce [68Ga]Ga-PSMA-11 for patient use in good activity yields (single generator, 0.52 GBq (14 mCi); dual generators, 1.04-1.57 GBq (28-42 mCi); cyclotron method (single target), 1.47-1.89 GBq (40-51 mCi); cyclotron method (dual target), 3.63 GBq (98 mCi)) and high radiochemical purity (99%) (UM, n = 645; RPA, n > 600). Both methods are appropriate for clinical production but, in the long term, the method employing cyclotron-produced 68Ga is the most promising for meeting high patient volumes. Quality control testing (visual inspection, pH, radiochemical purity and identity, radionuclidic purity and identity, sterile filter integrity, bacterial endotoxin content, sterility, stability) confirmed doses are suitable for clinical use, and there is no difference in clinical prostate cancer PET imaging using [68Ga]Ga-PSMA-11 prepared using the two production methods.
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Affiliation(s)
- Melissa E Rodnick
- University of Michigan, Department of Radiology, Division of Nuclear Medicine, Ann Arbor, MI, USA
| | | | - Daniela Stark
- Department of Molecular Imaging, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - Mara Clark
- University of Michigan, Department of Radiology, Division of Nuclear Medicine, Ann Arbor, MI, USA
| | - Andrew Katsifis
- Department of Molecular Imaging, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - Brian G Hockley
- University of Michigan, Department of Radiology, Division of Nuclear Medicine, Ann Arbor, MI, USA
| | | | - Jens Frigell
- GE Healthcare, GEMS PET Systems, Uppsala, Sweden
| | - Bradford D Henderson
- University of Michigan, Department of Radiology, Division of Nuclear Medicine, Ann Arbor, MI, USA
| | - Laura Bruton
- University of Michigan, Department of Radiology, Division of Nuclear Medicine, Ann Arbor, MI, USA
| | - Sean Preshlock
- University of Michigan, Department of Radiology, Division of Nuclear Medicine, Ann Arbor, MI, USA
| | - Monica Abghari-Gerst
- University of Michigan, Department of Radiology, Division of Nuclear Medicine, Ann Arbor, MI, USA
| | - Morand R Piert
- University of Michigan, Department of Radiology, Division of Nuclear Medicine, Ann Arbor, MI, USA
| | - Michael J Fulham
- Department of Molecular Imaging, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia.,Faculty of Engineering School of Computer Science, The University of Sydney, Sydney, New South Wales, Australia
| | - Stefan Eberl
- Department of Molecular Imaging, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia. .,Faculty of Engineering School of Computer Science, The University of Sydney, Sydney, New South Wales, Australia.
| | | | - Peter J H Scott
- University of Michigan, Department of Radiology, Division of Nuclear Medicine, Ann Arbor, MI, USA.
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Kaur T, Brooks AF, Hockley BG, Torres J, Henderson BD, Scott PJH, Shao X. An updated synthesis of N 1 '-([ 11 C]methyl)naltrindole for positron emission tomography imaging of the delta opioid receptor. J Labelled Comp Radiopharm 2020; 64:187-193. [PMID: 33274468 DOI: 10.1002/jlcr.3898] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 11/30/2020] [Accepted: 11/30/2020] [Indexed: 11/08/2022]
Abstract
A new method for the synthesis of the highly selective delta opioid receptor (DOR) antagonist radiotracer N1 '-([11 C]methyl)naltrindole ([11 C]MeNTI) is described. The original synthesis required hydrogenation of a benzyl protecting group after 11 C-labeling, which is challenging in modern radiochemistry laboratories that tend to be heavily automated and operate according to current good manufacturing practice. To address this challenge, we describe development of a novel MeNTI precursor bearing a methoxymethyl acetal (MOM) protecting group, which is easily removed with HCl, and employ it in an updated synthesis of [11 C]MeNTI. The new synthesis is fully automated and validated for clinical use. The total synthesis time is 45 min and provides [11 C]MeNTI in good activity yield (49 ± 8 mCi), molar activity (3,926 ± 326 Ci/mmol) and radiochemical purity (97% ± 2%).
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Affiliation(s)
- Tanpreet Kaur
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Allen F Brooks
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Brian G Hockley
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Jovany Torres
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Bradford D Henderson
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Peter J H Scott
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Xia Shao
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
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4
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Rodnick ME, Sollert C, Stark D, Clark M, Katsifis A, Hockley BG, Parr DC, Frigell J, Henderson BD, Abghari-Gerst M, Piert MR, Fulham MJ, Eberl S, Gagnon K, Scott PJH. Cyclotron-based production of 68Ga, [ 68Ga]GaCl 3, and [ 68Ga]Ga-PSMA-11 from a liquid target. EJNMMI Radiopharm Chem 2020; 5:25. [PMID: 33180205 PMCID: PMC7661618 DOI: 10.1186/s41181-020-00106-9] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Accepted: 10/19/2020] [Indexed: 11/10/2022] Open
Abstract
PURPOSE To optimize the direct production of 68Ga on a cyclotron, via the 68Zn(p,n)68Ga reaction using a liquid cyclotron target. We Investigated the yield of cyclotron-produced 68Ga, extraction of [68Ga]GaCl3 and subsequent [68Ga]Ga-PSMA-11 labeling using an automated synthesis module. METHODS Irradiations of a 1.0 M solution of [68Zn]Zn(NO3)2 in dilute (0.2-0.3 M) HNO3 were conducted using GE PETtrace cyclotrons and GE 68Ga liquid targets. The proton beam energy was degraded to a nominal 14.3 MeV to minimize the co-production of 67Ga through the 68Zn(p,2n)67Ga reaction without unduly compromising 68Ga yields. We also evaluated the effects of varying beam times (50-75 min) and beam currents (27-40 μA). Crude 68Ga production was measured. The extraction of [68Ga]GaCl3 was performed using a 2 column solid phase method on the GE FASTlab Developer platform. Extracted [68Ga]GaCl3 was used to label [68Ga]Ga-PSMA-11 that was intended for clinical use. RESULTS The decay corrected yield of 68Ga at EOB was typically > 3.7 GBq (100 mCi) for a 60 min beam, with irradiations of [68Zn]Zn(NO3)2 at 0.3 M HNO3. Target/chemistry performance was more consistent when compared with 0.2 M HNO3. Radionuclidic purity of 68Ga was typically > 99.8% at EOB and met the requirements specified in the European Pharmacopoeia (< 2% combined 66/67Ga) for a practical clinical product shelf-life. The activity yield of [68Ga]GaCl3 was typically > 50% (~ 1.85 GBq, 50 mCi); yields improved as processes were optimized. Labeling yields for [68Ga]Ga-PSMA-11 were near quantitative (~ 1.67 GBq, 45 mCi) at EOS. Cyclotron produced [68Ga]Ga-PSMA-11 underwent full quality control, stability and sterility testing, and was implemented for human use at the University of Michigan as an Investigational New Drug through the US FDA and also at the Royal Prince Alfred Hospital (RPA). CONCLUSION Direct cyclotron irradiation of a liquid target provides clinically relevant quantities of [68Ga]Ga-PSMA-11 and is a viable alternative to traditional 68Ge/68Ga generators.
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Affiliation(s)
- Melissa E Rodnick
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, MI, USA
| | | | - Daniela Stark
- Department of Molecular Imaging, Royal Prince Alfred Hospital, Sydney, Australia
| | - Mara Clark
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, MI, USA
| | - Andrew Katsifis
- Department of Molecular Imaging, Royal Prince Alfred Hospital, Sydney, Australia
| | - Brian G Hockley
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, MI, USA
| | | | - Jens Frigell
- GE Healthcare, GEMS PET Systems, Uppsala, Sweden
| | - Bradford D Henderson
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, MI, USA
| | - Monica Abghari-Gerst
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, MI, USA
| | - Morand R Piert
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, MI, USA
| | - Michael J Fulham
- Department of Molecular Imaging, Royal Prince Alfred Hospital and Sydney Medical School, University of Sydney, Sydney, Australia
| | - Stefan Eberl
- Department of Molecular Imaging, Royal Prince Alfred Hospital and School of Computer Science, The University of Sydney, Sydney, Australia.
| | | | - Peter J H Scott
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, MI, USA.
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5
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Jackson IM, Lee SJ, Sowa AR, Rodnick ME, Bruton L, Clark M, Preshlock S, Rothley J, Rogers VE, Botti LE, Henderson BD, Hockley BG, Torres J, Raffel DM, Brooks AF, Frey KA, Kilbourn MR, Koeppe RA, Shao X, Scott PJH. Use of 55 PET radiotracers under approval of a Radioactive Drug Research Committee (RDRC). EJNMMI Radiopharm Chem 2020; 5:24. [PMID: 33175263 PMCID: PMC7658275 DOI: 10.1186/s41181-020-00110-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 10/19/2020] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND In the US, EU and elsewhere, basic clinical research studies with positron emission tomography (PET) radiotracers that are generally recognized as safe and effective (GRASE) can often be conducted under institutional approval. For example, in the United States, such research is conducted under the oversight of a Radioactive Drug Research Committee (RDRC) as long as certain requirements are met. Firstly, the research must be for basic science and cannot be intended for immediate therapeutic or diagnostic purposes, or to determine the safety and effectiveness of the PET radiotracer. Secondly, the PET radiotracer must be generally recognized as safe and effective. Specifically, the mass dose to be administered must not cause any clinically detectable pharmacological effect in humans, and the radiation dose to be administered must be the smallest dose practical to perform the study and not exceed regulatory dose limits within a 1-year period. In our experience, the main barrier to using a PET radiotracer under RDRC approval is accessing the required information about mass and radioactive dosing. RESULTS The University of Michigan (UM) has a long history of using PET radiotracers in clinical research studies. Herein we provide dosing information for 55 radiotracers that will enable other PET Centers to use them under the approval of their own RDRC committees. CONCLUSIONS The data provided herein will streamline future RDRC approval, and facilitate further basic science investigation of 55 PET radiotracers that target functionally relevant biomarkers in high impact disease states.
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Affiliation(s)
- Isaac M Jackson
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
- Present Address: Stanford University, Stanford, CA, USA
| | - So Jeong Lee
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
- Present Address: Gordon Center for Medical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Alexandra R Sowa
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Melissa E Rodnick
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Laura Bruton
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Mara Clark
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Sean Preshlock
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Jill Rothley
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Virginia E Rogers
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Leslie E Botti
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Bradford D Henderson
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Brian G Hockley
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Jovany Torres
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - David M Raffel
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Allen F Brooks
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Kirk A Frey
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Michael R Kilbourn
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Robert A Koeppe
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Xia Shao
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA
| | - Peter J H Scott
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI, 48109, USA.
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Frank C, Winter G, Rensei F, Samper V, Brooks AF, Hockley BG, Henderson BD, Rensch C, Scott PJH. Development and implementation of ISAR, a new synthesis platform for radiopharmaceutical production. EJNMMI Radiopharm Chem 2019; 4:24. [PMID: 31659546 PMCID: PMC6751239 DOI: 10.1186/s41181-019-0077-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 08/30/2019] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND PET radiopharmaceutical development and the implementation of a production method on a synthesis module is a complex and time-intensive task since new synthesis methods must be adapted to the confines of the synthesis platform in use. Commonly utilized single fluid bus architectures put multiple constraints on synthesis planning and execution, while conventional microfluidic solutions are limited by compatibility at the macro-to-micro interface. In this work we introduce the ISAR synthesis platform and custom-tailored fluid paths leveraging up to 70 individually addressable valves on a chip-based consumable. The ISAR synthesis platform replaces traditional stopcock valve manifolds with a fluidic chip that integrates all fluid paths (tubing) and valves into one consumable and enables channel routing without the single fluid bus constraint. ISAR can scale between the macro- (10 mL), meso- (0.5 mL) and micro- (≤0.05 mL) domain seamlessly, addressing the macro-to-micro interface challenge and enabling custom tailored fluid circuits for a given application. In this paper we demonstrate proof-of-concept by validating a single chip design to address the challenge of synthesizing multiple batches of [13N]NH3 for clinical use throughout the workday. RESULTS ISAR was installed at an academic PET Center and used to manufacture [13N]NH3 in > 96% radiochemical yield. Up to 9 batches were manufactured with a single consumable chip having parallel paths without the need to open the hot-cell. Quality control testing confirmed the ISAR-based [13N]NH3 met existing clinical release specifications, and utility was demonstrated by imaging a rodent with [13N]NH3 produced on ISAR. CONCLUSIONS ISAR represents a new paradigm in radiopharmaceutical production. Through a new system architecture, ISAR integrates the principles of microfluidics with the standard volumes and consumables established in PET Centers all over the world. Proof-of-concept has been demonstrated through validation of a chip design for the synthesis of [13N]NH3 suitable for clinical use.
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Affiliation(s)
| | - Georg Winter
- GE Healthcare, Oskar-Schlemmer-Str. 11, 80807 Munich, Germany
| | | | | | - Allen F. Brooks
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI 48109 USA
| | - Brian G. Hockley
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI 48109 USA
| | - Bradford D. Henderson
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI 48109 USA
| | | | - Peter J. H. Scott
- Department of Radiology, University of Michigan, 2276 Medical Science Bldg I, SPC 5610, Ann Arbor, MI 48109 USA
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7
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Blecha JE, Henderson BD, Hockley BG, VanBrocklin HF, Zubieta JK, DaSilva AF, Kilbourn MR, Koeppe RA, Scott PJ, Shao X. An updated synthesis of [ 11 C]carfentanil for positron emission tomography (PET) imaging of the μ-opioid receptor. J Labelled Comp Radiopharm 2017; 60:375-380. [PMID: 28419528 PMCID: PMC9886010 DOI: 10.1002/jlcr.3513] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 04/10/2017] [Accepted: 04/11/2017] [Indexed: 02/01/2023]
Abstract
[11 C]Carfentanil ([11 C]CFN) is a selective radiotracer for in vivo positron emission tomography imaging studies of the μ-opioid system that, in our laboratories, is synthesized by methylation of the corresponding carboxylate precursor with [11 C]MeOTf, and purified using a C2 solid-phase extraction cartridge. Changes in the commercial availability of common C2 cartridges have necessitated future proofing the synthesis of [11 C]CFN to maintain reliable delivery of the radiotracer for clinical imaging studies. An updated synthesis of [11 C]CFN is reported that replaces a now obsolete purification cartridge with a new commercially available version and also substitutes the organic solvents used in traditional production methods with ethanol.
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Affiliation(s)
- Joseph E. Blecha
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA
| | | | - Brian G. Hockley
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Henry F. VanBrocklin
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA
| | - Jon-Kar Zubieta
- Department of Psychiatry, University Neuropsychiatric Institute, University of Utah Health Center, Salt Lake City, UT, USA
| | - Alexandre F. DaSilva
- Headache and Orofacial Pain Effort, Biologic and Materials Sciences Department, School of Dentistry, University of Michigan, Ann Arbor, MI, USA
| | - Michael R. Kilbourn
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Robert A. Koeppe
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Peter J.H. Scott
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Xia Shao
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI, USA
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8
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Mossine AV, Brooks AF, Henderson BD, Hockley BG, Frey KA, Scott PJH. An updated radiosynthesis of [ 18F]AV1451 for tau PET imaging. EJNMMI Radiopharm Chem 2017; 2:7. [PMID: 29503848 PMCID: PMC5824695 DOI: 10.1186/s41181-017-0027-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Accepted: 05/29/2017] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND [18F]AV1451 is a commonly used radiotracer for imaging tau deposits in Alzheimer's disease (AD) and related non-AD tauopathies. Existing radiosyntheses of [18F]AV1451 require complex purifications to provide doses suitable for use in clinical imaging studies. To address this issue, we have modified the synthesis of [18F]AV1451 to use only 0.5 mg precursor, optimized the Boc-deprotection step and developed a simplified method for HPLC purification of the radiotracer. RESULTS An optimized [18F]AV1451 synthesis using a TRACERLab FXFN module led to high radiochemical yield (202 ± 57 mCi per synthesis) and doses with excellent radiochemical purity (98 ± 1%) and good specific activity (2521 ± 623 Ci/mmol). CONCLUSION An updated and operationally simple synthesis of [18F]AV1451 has been developed that is fully automated and prepares radiotracer doses suitable for use in clinical tau PET studies.
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Affiliation(s)
- Andrew V. Mossine
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, MI 48109 USA
| | - Allen F. Brooks
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, MI 48109 USA
| | - Bradford D. Henderson
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, MI 48109 USA
| | - Brian G. Hockley
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, MI 48109 USA
| | - Kirk A. Frey
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, MI 48109 USA
| | - Peter J. H. Scott
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, MI 48109 USA
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9
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Piert M, Shao X, Raffel D, Davenport MS, Montgomery J, Kunju LP, Hockley BG, Siddiqui J, Scott PJH, Chinnaiyan AM, Rajendiran T. Preclinical Evaluation of 11C-Sarcosine as a Substrate of Proton-Coupled Amino Acid Transporters and First Human Application in Prostate Cancer. J Nucl Med 2017; 58:1216-1223. [PMID: 28302759 DOI: 10.2967/jnumed.116.173179] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 02/14/2017] [Indexed: 12/14/2022] Open
Abstract
Sarcosine is a known substrate of proton-coupled amino acid transporters (PATs), which are overexpressed in selected tissues and solid tumors. Sarcosine, an N-methyl derivative of the amino acid glycine and a metabolic product of choline, plays an important role for prostate cancer aggressiveness and progression. Methods:11C-radiolabeled sarcosine was tested as a new PET imaging probe in comparison with 11C-choline in 2 prostate cancer tumor xenograft models (DU-145 and PC-3). We characterized 11C-sarcosine transport in PC-3 and LNCaP tumor cells and performed 11C-sarcosine PET with CT in the first human subject with localized Gleason 4 + 3 prostate cancer. Target metabolite analyses of sarcosine and its natural precursors, glycine and choline, were performed from independent human prostate tissues. Results: In vitro assays indicated blockage of 11C-sarcosine uptake into PC-3 and LNCaP tumor cells by excess unlabeled (cold) sarcosine. 5-hydroxy-l-tryptophan, but not 2-aminobicyclo-(2,2,1)-heptane-2-carboxylic acid, competitively inhibited 11C-sarcosine tumor cell uptake, confirming PAT-mediated transport. In vivo tumor-to-background ratios (TBRs) obtained from 11C-sarcosine PET were significantly elevated compared with 11C-choline in DU-145 (TBR: 1.92 ± 0.11 for 11C-sarcosine vs. 1.41 ± 0.13 for 11C-choline [n = 10; P < 0.002]) and PC-3 tumors (TBR: 1.89 ± 0.2 for 11C-sarcosine vs. 1.34 ± 0.16 for 11C-choline [n = 7; P < 0.002]). 11C-sarcosine produced high-contrast images in 1 case of localized clinically significant prostate cancer. Target metabolite analyses revealed significant stepwise increases of sarcosine, glycine, and choline tissue levels from benign prostate tissue to localized prostate cancer and subsequently metastatic disease. 11C-sarcosine showed a favorable radiation dosimetry with an effective dose estimate of 0.0045 mSv/MBq, resulting in 2.68 mSv for a human subject (600-MBq dose). Conclusion:11C-sarcosine is a novel radiotracer for PATs and shows initial utility for prostate cancer imaging, with potential benefit over commonly used 11C-choline.
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Affiliation(s)
- Morand Piert
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Xia Shao
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - David Raffel
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | | | | | | | - Brian G Hockley
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Javed Siddiqui
- Pathology Department, University of Michigan, Ann Arbor, Michigan; and.,Michigan Center for Translational Pathology, University of Michigan, Ann Arbor, Michigan
| | - Peter J H Scott
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Arul M Chinnaiyan
- Pathology Department, University of Michigan, Ann Arbor, Michigan; and.,Michigan Center for Translational Pathology, University of Michigan, Ann Arbor, Michigan
| | - Thekkelnaycke Rajendiran
- Pathology Department, University of Michigan, Ann Arbor, Michigan; and.,Michigan Center for Translational Pathology, University of Michigan, Ann Arbor, Michigan
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10
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Scott PJH, Shao X, Desmond TJ, Hockley BG, Sherman P, Quesada CA, Frey KA, Koeppe RA, Kilbourn MR, Bohnen NI. Investigation of Proposed Activity of Clarithromycin at GABAA Receptors Using [(11)C]Flumazenil PET. ACS Med Chem Lett 2016; 7:746-50. [PMID: 27563397 DOI: 10.1021/acsmedchemlett.5b00435] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 06/01/2016] [Indexed: 11/28/2022] Open
Abstract
Clarithromycin is a potential treatment for hypersomnia acting through proposed negative allosteric modulation of GABAA receptors. We were interested whether this therapeutic benefit might extend to Parkinson's disease (PD) patients because GABAergic neurotransmission is implicated in postural control. Prior to initiating clinical studies in PD patients, we wished to better understand clarithromycin's mechanism of action. In this work we investigated whether the proposed activity of clarithromycin at the GABAA receptor is associated with the benzodiazepine binding site using in vivo [(11)C]flumazenil positron emission tomography (PET) in primates and ex vivo [(3)H]flumazenil autoradiography in rat brain. While the studies demonstrate that clarithromycin does not change the K d of FMZ, nor does it competitively displace FMZ, there is preliminary evidence from the primate PET imaging studies that clarithromycin delays dissociation and washout of flumazenil from the primate brain in a dose-dependent fashion. These findings would be consistent with the proposed GABAA allosteric modulator function of clarithromycin. While the results are only preliminary, further investigation of the interaction of clarithromycin with GABA receptors and/or GABAergic medications is warranted, and therapeutic applications of clarithromycin alone or in combination with flumazenil, to treat hyper-GABAergic status in PD at minimally effective doses, should also be pursued.
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Affiliation(s)
- Peter J. H. Scott
- Division of Nuclear Medicine, Department of Radiology, The University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
- The Interdepartmental Program in Medicinal Chemistry, The University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Xia Shao
- Division of Nuclear Medicine, Department of Radiology, The University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Timothy J. Desmond
- Division of Nuclear Medicine, Department of Radiology, The University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Brian G. Hockley
- Division of Nuclear Medicine, Department of Radiology, The University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Phillip Sherman
- Division of Nuclear Medicine, Department of Radiology, The University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Carole A. Quesada
- Division of Nuclear Medicine, Department of Radiology, The University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Kirk A. Frey
- Division of Nuclear Medicine, Department of Radiology, The University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
- Department
of Neurology, The University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Robert A. Koeppe
- Division of Nuclear Medicine, Department of Radiology, The University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Michael R. Kilbourn
- Division of Nuclear Medicine, Department of Radiology, The University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Nicolaas I. Bohnen
- Division of Nuclear Medicine, Department of Radiology, The University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
- Department
of Neurology, The University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
- Neurology Service and Geriatrics Research,
Education, and Clinical Center, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan United States
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11
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Stewart MN, Hockley BG, Scott PJH. Green approaches to late-stage fluorination: radiosyntheses of 18F-labelled radiopharmaceuticals in ethanol and water. Chem Commun (Camb) 2015; 51:14805-8. [DOI: 10.1039/c5cc05919d] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Green strategies for late-stage fluorination with 18F, in which ethanol and water are the only solvents used throughout the entire radiolabeling process, have been developed and applied to the radiosyntheses of a range of radiopharmaceuticals commonly employed in clinical PET imaging.
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Affiliation(s)
- Megan N. Stewart
- Department of Medicinal Chemistry
- College of Pharmacy
- The University of Michigan
- Ann Arbor
- USA
| | - Brian G. Hockley
- Division of Nuclear Medicine
- Department of Radiology
- The University of Michigan Medical School
- Ann Arbor
- USA
| | - Peter J. H. Scott
- Department of Medicinal Chemistry
- College of Pharmacy
- The University of Michigan
- Ann Arbor
- USA
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12
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Fawaz M, Brooks AF, Rodnick ME, Carpenter GM, Shao X, Desmond TJ, Sherman P, Quesada CA, Hockley BG, Kilbourn MR, Albin RL, Frey KA, Scott PJH. High affinity radiopharmaceuticals based upon lansoprazole for PET imaging of aggregated tau in Alzheimer's disease and progressive supranuclear palsy: synthesis, preclinical evaluation, and lead selection. ACS Chem Neurosci 2014; 5:718-30. [PMID: 24896980 PMCID: PMC4140593 DOI: 10.1021/cn500103u] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2014] [Revised: 06/04/2014] [Indexed: 01/05/2023] Open
Abstract
Abnormally aggregated tau is the hallmark pathology of tauopathy neurodegenerative disorders and is a target for development of both diagnostic tools and therapeutic strategies across the tauopathy disease spectrum. Development of carbon-11- or fluorine-18-labeled radiotracers with appropriate affinity and specificity for tau would allow noninvasive quantification of tau burden using positron emission tomography (PET) imaging. We have synthesized [(18)F]lansoprazole, [(11)C]N-methyl lansoprazole, and [(18)F]N-methyl lansoprazole and identified them as high affinity radiotracers for tau with low to subnanomolar binding affinities. Herein, we report radiosyntheses and extensive preclinical evaluation with the aim of selecting a lead radiotracer for translation into human PET imaging trials. We demonstrate that [(18)F]N-methyl lansoprazole, on account of the favorable half-life of fluorine-18 and its rapid brain entry in nonhuman primates, favorable kinetics, low white matter binding, and selectivity for binding to tau over amyloid, is the lead compound for progression into clinical trials.
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Affiliation(s)
- Maria
V. Fawaz
- Division
of Nuclear Medicine, Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Allen F. Brooks
- Division
of Nuclear Medicine, Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Melissa E. Rodnick
- Division
of Nuclear Medicine, Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Garrett M. Carpenter
- Division
of Nuclear Medicine, Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Xia Shao
- Division
of Nuclear Medicine, Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Timothy J. Desmond
- Division
of Nuclear Medicine, Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Phillip Sherman
- Division
of Nuclear Medicine, Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Carole A. Quesada
- Division
of Nuclear Medicine, Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Brian G. Hockley
- Division
of Nuclear Medicine, Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Michael R. Kilbourn
- Division
of Nuclear Medicine, Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Roger L. Albin
- Geriatrics
Research, Education and Clinical Center, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan 48105, United States
- Department
of Neurology, The University of Michigan
Medical School, Ann Arbor, Michigan 48109, United States
- Michigan Alzheimer
Disease Center and The Interdepartmental Program in
Medicinal Chemistry, The University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Kirk A. Frey
- Division
of Nuclear Medicine, Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Peter J. H. Scott
- Division
of Nuclear Medicine, Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
- Michigan Alzheimer
Disease Center and The Interdepartmental Program in
Medicinal Chemistry, The University of Michigan, Ann Arbor, Michigan 48109, United States
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13
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Rodnick ME, Hockley BG, Sherman P, Quesada C, Battle MR, Jackson A, Linder KE, Macholl S, Trigg WJ, Kilbourn MR, Scott PJH. Novel fluorine-18 PET radiotracers based on flumazenil for GABAA imaging in the brain. Nucl Med Biol 2013; 40:901-5. [PMID: 23890694 DOI: 10.1016/j.nucmedbio.2013.06.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2013] [Revised: 06/08/2013] [Accepted: 06/14/2013] [Indexed: 10/26/2022]
Abstract
INTRODUCTION Two 7-fluoroimidazobenzodiazepines (AH114726 and GEH120348), analogs of flumazenil, were labeled with fluorine-18 and evaluated as alternative radioligands for in vivo imaging of the GABAA/benzodiazepine receptor by comparing them to [(11)C]flumazenil in rhesus monkey. METHODS Radiotracers were prepared from the corresponding nitro-precursors in an automated synthesis module, and primate imaging studies were conducted on a Concorde MicroPET P4 scanner. The brain was imaged for 60 (12 × 5 min frames) or 90 min (18 × 5 min frames), and data was reconstructed using the 3D MAP algorithm. Specificity of [(18)F]AH114726 and [(18)F]GEH120348 was confirmed by displacement studies using unlabeled flumazenil. RESULTS [(18)F]GEH120348 and [(18)F]AH114726 were obtained in 13-24% yields (end of synthesis) with high chemical (>95%) and radiochemical (>99%) purities, and high specific activities (2061 ± 985 Ci/mmol). The in vivo pharmacokinetics of [(18)F]AH114726 and [(18)F]GEH120348 were determined in a non-human primate and directly compared with [(11)C]flumazenil. Both fluorine-18 radioligands showed time-dependent regional brain distributions that correlated with the distribution of [(11)C]flumazenil and the known concentrations of GABAA/benzodiazepine receptors in the monkey brain. [(18)F]AH114726 exhibited maximal brain uptake and tissue time-radioactivity curves that were most similar to [(11)C]flumazenil. In contrast, [(18)F]GEH120348 showed higher initial brain uptake but very different pharmacokinetics with continued accumulation of radioactivity into the cortical regions of high GABA/benzodiazepine receptor concentrations and very little clearance from the regions of low receptor densities. Rapid washout of both radiotracers occurred upon treatment with unlabeled flumazenil. CONCLUSION The ease of the radiochemical synthesis, together with in vivo brain pharmacokinetics most similar to [(11)C]flumazenil, support that [(18)F]AH114726 is a suitable option for imaging the GABAA receptor.
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Affiliation(s)
- Melissa E Rodnick
- Division of Nuclear Medicine, Department of Radiology, University of Michigan Medical School, Ann Arbor, MI, USA
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14
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Hockley BG, Stewart MN, Sherman P, Quesada C, Kilbourn MR, Albin RL, Scott PJH. (-)-[(18) F]Flubatine: evaluation in rhesus monkeys and a report of the first fully automated radiosynthesis validated for clinical use. J Labelled Comp Radiopharm 2013; 56:595-9. [PMID: 24285235 DOI: 10.1002/jlcr.3069] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Revised: 05/09/2013] [Accepted: 05/12/2013] [Indexed: 11/10/2022]
Abstract
(-)-[(18) F]Flubatine was selected for clinical imaging of α4 β2 nicotinic acetylcholine receptors because of its high affinity and appropriate kinetic profile. A fully automated synthesis of (-)-[(18) F]flubatine as a sterile isotonic solution suitable for clinical use is reported, as well as the first evaluation in nonhuman primates (rhesus macaques). (-)-[(18) F]Flubatine was prepared by fluorination of the Boc-protected trimethylammonium iodide precursor with [(18) F]fluoride in an automated synthesis module. Subsequent deprotection of the Boc group with 1-M HCl yielded (-)-[(18) F]flubatine, which was purified by semi-preparative HPLC. (-)-[(18) F]Flubatine was prepared in 25% radiochemical yield (formulated for clinical use at end of synthesis, n = 3), >95% radiochemical purity, and specific activity = 4647 Ci/mmol (171.9 GBq/µmol). Doses met all quality control criteria confirming their suitability for clinical use. Evaluation of (-)-[(18) F]flubatine in rhesus macaques was performed with a Concorde MicroPET P4 scanner (Concorde MicroSystems, Knoxville, TN). The brain was imaged for 90 min, and data were reconstructed using the 3-D maximum a posteriori algorithm. Image analysis revealed higher uptake and slower washout in the thalamus than those in other areas of the brain and peak uptake at 45 min. Injection of 2.5 µg/kg of nifene at 60 min initiated a slow washout of [(18) F]flubatine, with about 25% clearance from the thalamus by the end of imaging at 90 min.
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Affiliation(s)
- Brian G Hockley
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI, USA
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15
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Rodnick ME, Brooks AF, Hockley BG, Henderson BD, Scott PJH. A fully-automated one-pot synthesis of [18F]fluoromethylcholine with reduced dimethylaminoethanol contamination via [18F]fluoromethyl tosylate. Appl Radiat Isot 2013; 78:26-32. [PMID: 23665261 DOI: 10.1016/j.apradiso.2013.04.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Revised: 04/02/2013] [Accepted: 04/08/2013] [Indexed: 02/02/2023]
Abstract
INTRODUCTION A novel one-pot method for preparing [(18)F]fluoromethylcholine ([(18)F]FCH) via in situ generation of [(18)F]fluoromethyl tosylate ([(18)F]FCH2OTs), and subsequent [(18)F]fluoromethylation of dimethylaminoethanol (DMAE), has been developed. METHODS [(18)F]FCH was prepared using a GE TRACERlab FXFN, although the method should be readily adaptable to any other fluorine-(18) synthesis module. Initially ditosylmethane was fluorinated to generate [(18)F]FCH2OTs. DMAE was then added and the reaction was heated at 120 °C for 10 min to generate [(18)F]FCH. After this time, reaction solvent was evaporated, and the crude reaction mixture was purified by solid-phase extraction using C(18)-Plus and CM-Light Sep-Pak cartridges to provide [(18)F]FCH formulated in USP saline. The formulated product was passed through a 0.22 µm filter into a sterile dose vial, and submitted for quality control testing. Total synthesis time was 1.25 h from end-of-bombardment. RESULTS Typical non-decay-corrected yields of [(18)F]FCH prepared using this method were 91 mCi (7% non-decay corrected based upon ~1.3 Ci [(18)F]fluoride), and doses passed all other quality control (QC) tests. CONCLUSION A one-pot liquid-phase synthesis of [(18)F]FCH has been developed. Doses contain extremely low levels of residual DMAE (31.6 µg/10 mL dose or ~3 ppm) and passed all other requisite QC testing, confirming their suitability for use in clinical imaging studies.
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Affiliation(s)
- Melissa E Rodnick
- Division of Nuclear Medicine, Department of Radiology, The University of Michigan Medical School, Ann Arbor, MI 48109, USA
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16
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Shao X, Hoareau R, Runkle AC, Tluczek LJM, Hockley BG, Henderson BD, Scott PJH. Highlighting the versatility of the Tracerlab synthesis modules. Part 2: fully automated production of [11C]-labeled radiopharmaceuticals using a Tracerlab FXC-Pro. J Labelled Comp Radiopharm 2011. [DOI: 10.1002/jlcr.1937] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Xia Shao
- Department of Radiology; The University of Michigan School of Medicine; Ann Arbor; MI; 48109; USA
| | - Raphaël Hoareau
- Department of Radiology; The University of Michigan School of Medicine; Ann Arbor; MI; 48109; USA
| | - Adam C. Runkle
- Department of Radiology; The University of Michigan School of Medicine; Ann Arbor; MI; 48109; USA
| | - Louis J. M. Tluczek
- Department of Radiology; The University of Michigan School of Medicine; Ann Arbor; MI; 48109; USA
| | - Brian G. Hockley
- Department of Radiology; The University of Michigan School of Medicine; Ann Arbor; MI; 48109; USA
| | - Bradford D. Henderson
- Department of Radiology; The University of Michigan School of Medicine; Ann Arbor; MI; 48109; USA
| | - Peter J. H. Scott
- Department of Radiology; The University of Michigan School of Medicine; Ann Arbor; MI; 48109; USA
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17
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Shao X, Hoareau R, Hockley BG, Tluczek LJM, Henderson BD, Padgett HC, Scott PJH. Highlighting the Versatility of the Tracerlab Synthesis Modules. Part 1: Fully Automated Production of [F]Labelled Radiopharmaceuticals using a Tracerlab FX(FN). J Labelled Comp Radiopharm 2011; 54:292-307. [PMID: 21769163 PMCID: PMC3137381 DOI: 10.1002/jlcr.1865] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The field of radiochemistry is moving towards exclusive use of automated synthesis modules for production of clinical radiopharmaceutical doses. Such a move comes with many advantages, but also presents radiochemists with the challenge of re-configuring synthesis modules for production of radiopharmaceuticals that require non-conventional radiochemistry whilst maintaining full automation. This review showcases the versatility of the Tracerlab FX(FN) synthesis module by presenting simple, fully automated methods for producing [(18)F]FLT, [(18)F]FAZA, [(18)F]MPPF, [(18)F]FEOBV, [(18)F]sodium fluoride, [(18)F]fluorocholine and [(18)F]SFB.
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Affiliation(s)
- Xia Shao
- The University of Michigan School of Medicine, Ann Arbor, MI, USA
| | - Raphaël Hoareau
- The University of Michigan School of Medicine, Ann Arbor, MI, USA
| | - Brian G. Hockley
- The University of Michigan School of Medicine, Ann Arbor, MI, USA
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18
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Shao X, Hockley BG, Hoareau R, Schnau PL, Scott PJ. Fully automated preparation of [11C]choline and [18F]fluoromethylcholine using TracerLab synthesis modules and facilitated quality control using analytical HPLC. Appl Radiat Isot 2011; 69:403-9. [DOI: 10.1016/j.apradiso.2010.09.022] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2010] [Revised: 07/30/2010] [Accepted: 09/30/2010] [Indexed: 10/19/2022]
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19
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Runkle AC, Shao X, Tluczek LJM, Henderson BD, Hockley BG, Scott PJH. Automated production of [11C]acetate and [11C]palmitate using a modified GE Tracerlab FX(C-Pro). Appl Radiat Isot 2011; 69:691-8. [PMID: 21256039 DOI: 10.1016/j.apradiso.2011.01.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Revised: 12/22/2010] [Accepted: 01/03/2011] [Indexed: 11/16/2022]
Abstract
As researchers explore new applications for positron emission tomography radiopharmaceuticals, the demand for effective and readily available radiopharmaceuticals continues to increase. The syntheses of two such radiopharmaceuticals, [(11)C]acetate and [(11)C]palmitate, can be automated on the GE Tracerlab FX(C-Pro) by utilizing Grignard reactions. Radiochemical purities of the [(11)C]acetate and the [(11)C]palmitate products were high (>98% and >99.9%, respectively) with average non-corrected yields of 18% (n = 3) and 10% (n = 5), respectively. These data comprise the validation trials for site qualification of clinical production of both radiopharmaceuticals.
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Affiliation(s)
- Adam C Runkle
- Department of Radiology, University of Michigan Medical School, Ann Arbor, 48109, USA
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20
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Hockley BG, Scott PJH. An automated method for preparation of [(18)F]sodium fluoride for injection, USP to address the technetium-99m isotope shortage. Appl Radiat Isot 2009; 68:117-9. [PMID: 19762249 DOI: 10.1016/j.apradiso.2009.08.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Accepted: 08/20/2009] [Indexed: 11/16/2022]
Abstract
The worldwide shortage of technetium-99m has created an immediate and urgent need for access to [(18)F]sodium fluoride for PET imaging of bone metastasis. In order to facilitate global availability of [(18)F]sodium fluoride for diagnostic nuclear medicine imaging procedures, a straightforward method for rapid production of [(18)F]sodium fluoride for injection, USP, using a modified GE Tracerlab FX-FN is presented.
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Affiliation(s)
- Brian G Hockley
- The University of Michigan School of Medicine, Ann Arbor, MI, USA
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21
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Scott PJH, Hockley BG, Kung HF, Manchanda R, Zhang W, Kilbourn MR. Studies into radiolytic decomposition of fluorine-18 labeled radiopharmaceuticals for positron emission tomography. Appl Radiat Isot 2008; 67:88-94. [PMID: 18951032 DOI: 10.1016/j.apradiso.2008.08.015] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2007] [Revised: 08/21/2008] [Accepted: 08/26/2008] [Indexed: 11/25/2022]
Abstract
Radiolytic decomposition of high specific concentration radiopharmaceuticals is an undesired side-effect that can hamper development of novel PET tracers. This was particularly evident in a series of carbon-11 and fluorine-18 labeled mono- and dimethyl-substituted aryl amines, where rapid decomposition was observed in isolation and formulation steps. We tested a number of additives that inhibit radiolysis and can be safely added to the synthesis procedures (purification and isolation) and reformulation steps to provide suitable clinical formulations. Ethanol and sodium ascorbate are established anti-oxidant stabilizers that completely inhibit radiolytic decomposition and are amenable to human use. Herein, we also demonstrate for the first time that nitrones are non-toxic radical scavengers that are capable of inhibiting radiolysis.
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Affiliation(s)
- Peter J H Scott
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI, USA
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