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Wurzer A, De Rose F, Fischer S, Schwaiger M, Weber W, Nekolla S, Wester HJ, Eiber M, D'Alessandria C. Preclinical comparison of [ 177Lu]Lu-rhPSMA-10.1 and [ 177Lu]Lu-rhPSMA-10.2 for endoradiotherapy of prostate cancer: biodistribution and dosimetry studies. EJNMMI Radiopharm Chem 2024; 9:18. [PMID: 38407630 PMCID: PMC10897098 DOI: 10.1186/s41181-024-00246-2] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 02/20/2024] [Indexed: 02/27/2024] Open
Abstract
BACKGROUND Radiohybrid PSMA-targeted ligands (rhPSMA) have been introduced as a novel platform for theranostic applications. Among a variety of rhPSMA-ligands developed for radioligand therapy, two stereoisomers [177Lu]Lu-rhPSMA-10.1 and -10.2 have been synthesized and initially characterized in preclinical experiments with the aim to provide an optimized binding profile to human serum albumin, a reduction of charge, and thus accelerated kidney excretion, and unaffected or even improved tumor uptake. As both isomers showed similar in vitro characteristics and tumor uptake at 24 h post injection in tumor bearing mice and in order to identify the isomer with the most favorable pharmacokinetics for radioligand therapy, we carried out in-depth biodistribution and dosimetry studies in tumor-bearing and healthy mice. RESULTS rhPSMA-10.1 and -10.2 were radiolabeled with lutetium-177 according to the established procedures of other DOTA-based PSMA ligands and displayed a high and comparable stability in all buffers and human serum (> 97%, 24 h). Biodistribution studies revealed fast clearance from the blood pool (0.3-0.6%ID/g at 1 h) and other background tissues within 48 h. Distinctive differences were found in the kidneys, where [177Lu]Lu-rhPSMA-10.1 displayed lower initial uptake and faster excretion kinetics compared to [177Lu]Lu-rhPSMA-10.2 expressed by a 1.5-fold and ninefold lower uptake value at 1 h and 24 h in healthy animals, respectively. Tumor uptake was comparable and in the range of 8.6-11.6%ID/g for both isomers over 24 h and was maintained up to 168 h at a level of 2.2 ± 0.8 and 4.1 ± 1.4%ID/g for [177Lu]Lu-rhPSMA-10.1 and [177Lu]Lu-rhPSMA-10.2, respectively. CONCLUSION Our preclinical data on biodistribution and dosimetry indicate a more favorable profile of [177Lu]Lu-rhPSMA-10.1 compared to [177Lu]Lu-rhPSMA-10.2 for PSMA-targeted radioligand therapy. [177Lu]Lu-rhPSMA-10.1 shows fast kidney clearance kinetics resulting in excellent tumor-to-organ ratios over a therapy relevant time course. Meanwhile, [177Lu]Lu-rhPSMA-10.1 is currently being investigated in clinical phase I/II studies in patients with mCRPC (NCT05413850), in patients with high-risk localized PC (NCT06066437, Nautilus Trial) and after external beam radiotherapy (NCT06105918).
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Affiliation(s)
- Alexander Wurzer
- Department of Nuclear Medicine, University Hospital rechts der Isar, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany.
| | - Francesco De Rose
- Department of Nuclear Medicine, University Hospital rechts der Isar, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany
| | - Sebastian Fischer
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany
| | - Markus Schwaiger
- Department of Nuclear Medicine, University Hospital rechts der Isar, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany
| | - Wolfgang Weber
- Department of Nuclear Medicine, University Hospital rechts der Isar, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany
| | - Stephan Nekolla
- Department of Nuclear Medicine, University Hospital rechts der Isar, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany
| | - Hans-Jürgen Wester
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany
| | - Matthias Eiber
- Department of Nuclear Medicine, University Hospital rechts der Isar, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany
| | - Calogero D'Alessandria
- Department of Nuclear Medicine, University Hospital rechts der Isar, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany
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Kroenke M, Schweiger L, Horn T, Haller B, Schwamborn K, Wurzer A, Maurer T, Wester HJ, Eiber M, Rauscher I. Validation of 18F-rhPSMA-7 and 18F-rhPSMA-7.3 PET Imaging Results with Histopathology from Salvage Surgery in Patients with Biochemical Recurrence of Prostate Cancer. J Nucl Med 2022; 63:1809-1814. [PMID: 35393348 PMCID: PMC9730917 DOI: 10.2967/jnumed.121.263707] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [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: 12/25/2021] [Revised: 03/28/2022] [Indexed: 01/11/2023] Open
Abstract
18F-rhPSMA-7, and its single diastereoisomer form, 18F-rhPSMA-7.3, are prostate-specific membrane antigen (PSMA)-targeting radiopharmaceuticals. Here, we investigated their accuracy for the assessment of lymph node (LN) metastases validated by histopathology. Methods: Data from 58 patients with biochemical recurrence of prostate cancer after radical prostatectomy receiving salvage surgery after PET imaging with 18F-rhPSMA-7 or 18F-rhPSMA-7.3 were retrospectively reviewed. Two nuclear medicine physicians reviewed all PET scans and morphologic imaging in consensus. Readers were masked from the results of histopathology. PET and morphologic imaging were correlated with histopathology from resected LNs. Results: In 75 of 150 resected regions in 54 of 58 patients, tumor lesions were present in histopathology. The template-based specificity of PET (18F-rhPSMA-7 and 18F-rhPSMA-7.3 combined) and morphologic imaging was 93.3% and 100%, respectively. However, 18F-rhPSMA-7 and 18F-rhPSMA-7.3 PET detected metastases in 61 of 75 histopathologically proven metastatic LN fields (81.3%) whereas morphologic imaging was positive in only 9 of 75 (12.0%). The positive predictive value was 92.4% for 18F-rhPSMA-7 and 18F-rhPSMA-7.3 PET and 100% for morphologic imaging. 18F-rhPSMA-7 and 18F-rhPSMA-7.3 PET performance was significantly superior to morphologic imaging (difference in the areas under the receiver-operating-characteristic curves, 0.222; 95% CI, 0.147-0.298; P < 0.001). The mean size of PET-positive and histologically confirmed LN metastases was 6.3 ± 3.1 mm (range, 2-15 mm) compared with a mean size of 9.8 ± 2.5 mm (range, 7-15 mm) on morphologic imaging. Conclusion: 18F-rhPSMA-7 and 18F-rhPSMA-7.3 PET offer a high positive predictive value comparable to that reported for 68Ga-PSMA-11 and represent a valuable tool for guiding salvage lymphadenectomy.
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Affiliation(s)
- Markus Kroenke
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany;,Department of Radiology and Nuclear Medicine, German Heart Center Munich, Technical University of Munich, Munich, Germany
| | - Lilit Schweiger
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany;,Bavarian Cancer Research Center (BZKF), Munich, Germany
| | - Thomas Horn
- Department of Urology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Bernhard Haller
- Institute of Medical Informatics, Statistics and Epidemiology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Kristina Schwamborn
- Department of Pathology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Alexander Wurzer
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany;,Chair of Radiopharmacy, School of Medicine, Technical University of Munich, Munich, Germany; and
| | - Tobias Maurer
- Martini-Klinik and Department of Urology, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Hans-Jürgen Wester
- Chair of Radiopharmacy, School of Medicine, Technical University of Munich, Munich, Germany; and
| | - Matthias Eiber
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany;,Bavarian Cancer Research Center (BZKF), Munich, Germany
| | - Isabel Rauscher
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany;,Bavarian Cancer Research Center (BZKF), Munich, Germany
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Ilhan H, Kroenke M, Wurzer A, Unterrainer M, Heck M, Belka C, Knorr K, Langbein T, Rauscher I, Schmidt-Hegemann NS, Schiller K, Bartenstein P, Wester HJ, Eiber M. 18F-rhPSMA-7 PET for the Detection of Biochemical Recurrence of Prostate Cancer After Curative-Intent Radiation Therapy: A Bicentric Retrospective Study. J Nucl Med 2022; 63:1208-1214. [PMID: 35273094 PMCID: PMC9364349 DOI: 10.2967/jnumed.121.262861] [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] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 12/02/2021] [Indexed: 02/03/2023] Open
Abstract
This bicentric, retrospective analysis investigated the efficacy of PET/CT with a novel theranostic prostate-specific membrane antigen (PSMA)--targeting ligand, 18F-rhPSMA-7, in patients with biochemical recurrence (BCR) of prostate cancer after curative-intent primary radiotherapy. Methods: Datasets from patients with BCR of prostate cancer after external-beam radiation therapy or brachytherapy who underwent 18F-rhPSMA-7 PET/CT at either Technical University Munich or Ludwig-Maximilians-University Munich were retrospectively reviewed by experienced nuclear medicine physicians and radiologists at both centers. The median injected activity was 299 MBq (range, 204-420 MBq), and the median uptake time was 77 min (range, 46-120 min). All lesions suggestive of recurrent prostate cancer were noted. Detection rates were correlated with patients' prostate-specific antigen (PSA) level, primary Gleason score, and prior use of androgen-deprivation therapy (ADT). Results: Ninety-seven patients were included (65 at Technical University Munich and 32 at Ludwig-Maximilians-University Munich). The median prescan PSA was 4.19 ng/mL (range, 0.1-159 ng/mL). The primary Gleason score was ≤6 in 19 patients, 7 in 25, ≥8 in 33, and unknown in 20. Thirty patients received ADT in the 6 mo preceding PET/CT. 18F-rhPSMA-7 identified lesions in 91 of 97 (94%) patients. Detection rates stratified by PSA were 88% (22/25), 97% (30/31), 90% (19/21), and 100% (20/20) for a PSA of <2, 2-<5, 5-<10, and ≥10 ng/mL, respectively. Detection rates in the subgroup of patients not meeting the Phoenix criteria for BCR were 80% (4/5), 90% (9/10), 100% (4/4), and 83% (5/6) for a PSA of <0.5, 0.5-<1, 1-<1.5, and 1.5-2 ng/mL, respectively. There were no significant differences in detection rates between patients with and without prior ADT (100% vs. 91%, P = 0.173) or patients with a Gleason score of ≤7 and a Gleason score of ≥8 (98% vs. 91%, P = 0.316).18F-rhPSMA-7 revealed local recurrence in 80% (78/97); pelvic lymph node metastases in 38% (37/97); retroperitoneal and supradiaphragmatic lymph node metastases in 9% (9/97) and 4% (4/97), respectively; bone metastases in 27% (26/97); and visceral metastases in 3% (3/97). In the subgroup of patients with a PSA of <2 ng/mL above nadir, local recurrence occurred in 76% (19/25) and pelvic lymph node metastases in 36% (9/25). Conclusion:18F-rhPSMA-7 PET/CT demonstrates high detection rates in prostate cancer patients with BCR after primary radiation therapy, even at low PSA values. Its diagnostic efficacy is comparable to published data for other PSMA ligands.
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Affiliation(s)
- Harun Ilhan
- Department of Nuclear Medicine, University Hospital, LMU Munich, Munich, Germany;,Die Radiologie, Munich, Germany
| | - Markus Kroenke
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany
| | - Alexander Wurzer
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany
| | - Marcus Unterrainer
- Department of Nuclear Medicine, University Hospital, LMU Munich, Munich, Germany;,Department of Radiology, University Hospital, LMU Munich, Munich, Germany
| | - Matthias Heck
- Department of Urology, Technical University of Munich, Munich, Germany
| | - Claus Belka
- Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany; and
| | - Karina Knorr
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany
| | - Thomas Langbein
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany
| | - Isabel Rauscher
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany
| | | | - Kilian Schiller
- Department of Radiation Oncology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Peter Bartenstein
- Department of Nuclear Medicine, University Hospital, LMU Munich, Munich, Germany
| | - Hans-Jürgen Wester
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany
| | - Matthias Eiber
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany
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Feuerecker B, Chantadisai M, Allmann A, Tauber R, Allmann J, Steinhelfer L, Rauscher I, Wurzer A, Wester HJ, Weber WA, d'Alessandria C, Eiber M. Pretherapeutic Comparative Dosimetry of 177Lu-rhPSMA-7.3 and 177Lu-PSMA I&T in Patients with Metastatic Castration-Resistant Prostate Cancer. J Nucl Med 2022; 63:833-839. [PMID: 34531260 PMCID: PMC9157737 DOI: 10.2967/jnumed.121.262671] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 08/26/2021] [Indexed: 11/16/2022] Open
Abstract
Radiohybrid prostate-specific membrane antigen (rhPSMA) ligands allow for labeling with 18F and radiometals for endoradiotherapy. rhPSMA-7.3 has been designated as a lead compound with promising preclinical data for 177Lu-rhPSMA-7.3, which has shown higher tumor uptake than 177Lu-PSMA I&T. In this retrospective analysis, we compared pretherapeutic clinical dosimetry data of both PSMA ligands. Methods: Six patients with metastatic castration-resistant prostate cancer underwent both 177Lu-rhPSMA-7.3 and 177Lu-PSMA I&T pretherapeutic dosimetry. Whole-body scintigraphy was performed at 1 h, 4 h, 24 h, 48 h, and 7 d after injection. Regions of interest covering the whole body, organs, bone marrow, and tumor lesions were drawn for each patient. Absorbed doses for individual patients and pretherapeutic applications were calculated using OLINDA/EXM. To facilitate the comparison of both ligands, we introduced the therapeutic index (TI), defined as the ratio of mean pretherapeutic doses to tumor lesions over relevant organs at risk. Results: Mean whole-body pretherapeutic effective doses for 177Lu-rhPSMA-7.3 and 177Lu-PSMA I&T were 0.12 ± 0.07 and 0.05 ± 0.03 Sv/GBq, respectively. Mean absorbed organ doses for 177Lu-rhPSMA-7.3 and 177Lu-PSMA I&T were, for example, 1.65 ± 0.28 and 0.73 ± 0.18 Gy/GBq for the kidneys, 0.19 ± 0.09 and 0.07 ± 0.03 Gy/GBq for the liver, 2.35 ± 0.78 and 0.80 ± 0.41 Gy/GBq for the parotid gland, and 0.67 ± 0.62 and 0.30 ± 0.27 Gy/GBq for the bone marrow, respectively. Tumor lesions received mean absorbed doses of 177Lu-rhPSMA-7.3 and 177Lu-PSMA I&T of 6.44 ± 6.44 and 2.64 ± 2.24 Gy/GBq, respectively. The mean TIs for the kidneys were 3.7 ± 2.2 and 3.6 ± 2.2 for 177Lu-rhPSMA-7.3 and 177Lu-PSMA I&T, respectively, and those for the bone marrow were 15.2 ± 10.2 and 15.1 ± 10.2 for 177Lu-rhPSMA-7.3 and 177Lu-PSMA I&T, respectively. Conclusion: Pretherapeutic clinical dosimetry confirmed preclinical results of mean absorbed doses for tumors that were 2-3 times higher for 177Lu-rhPSMA-7.3 than for 177Lu-PSMA I&T. Absorbed doses to normal organs also tended to be higher for 177Lu-rhPSMA-7.3, resulting overall in similar average TIs for both radiopharmaceuticals with considerable interpatient variability. 177Lu-rhPSMA-7.3 has promise for a therapeutic efficacy similar to that of 177Lu-PSMA I&T at smaller amounts of injected activity, simplifying radiation safety measurements (especially for large patient numbers or dose escalation regimens).
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Affiliation(s)
- Benedikt Feuerecker
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, München, Germany;
- Partnersite München, German Cancer Consortium (DKTK), Heidelberg, Germany
- Department of Radiology, School of Medicine, Technical University of Munich, München, Germany
| | - Maythinee Chantadisai
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, München, Germany
| | - Anne Allmann
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, München, Germany
| | - Robert Tauber
- Department of Urology, School of Medicine, Technical University of Munich, München, Germany; and
| | - Jakob Allmann
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, München, Germany
| | - Lisa Steinhelfer
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, München, Germany
| | - Isabel Rauscher
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, München, Germany
| | - Alexander Wurzer
- Department of Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany
| | - Hans-Jürgen Wester
- Department of Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany
| | - Wolfgang A Weber
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, München, Germany
- Partnersite München, German Cancer Consortium (DKTK), Heidelberg, Germany
| | - Calogero d'Alessandria
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, München, Germany
| | - Matthias Eiber
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, München, Germany
- Partnersite München, German Cancer Consortium (DKTK), Heidelberg, Germany
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Knorr K, Oh SW, Krönke M, Wurzer A, D'Alessandria C, Herz M, Weber W, Wester HJ, Eiber M, Yusufi N, Nekolla S. Preclinical biodistribution and dosimetry and human biodistribution comparing 18F-rhPSMA-7 and single isomer 18F-rhPSMA-7.3. EJNMMI Res 2022; 12:8. [PMID: 35119557 PMCID: PMC8816989 DOI: 10.1186/s13550-021-00872-w] [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] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 12/06/2021] [Indexed: 12/03/2022] Open
Abstract
Background Radiohybrid prostate-specific membrane antigen (rhPSMA) ligands such as 18F-rhPSMA-7 are a new class of theranostic agents in clinical development for prostate cancer. We compared preclinical dosimetry and human biodistribution of 18F-rhPSMA-7 with that of single diastereoisomer form, 18F-rhPSMA-7.3. Methods Preclinical dosimetry was performed with SCID-mice sacrificed at multiple timepoints (10–300 min) post-injection of 25.6 ± 3.6 MBq 18F-rhPSMA-7 or 28.5 ± 4.8 MBq 18F-rhPSMA-7.3 (n = 3–6 mice per timepoint). Heart, lung, liver, spleen, pancreas, fat, stomach, small intestine, large intestine, kidney, muscle, bone, bladder, testicles, tail, and brain tissue were harvested, and urine and blood samples collected. Percentage of injected dose per gram was calculated. Absorbed doses were estimated with OLINDA/EXM 1.0. 18F-rhPSMA-7 (n = 47) and 18F-rhPSMA-7.3 (n = 33) PET/CT exams were used to estimate human biodistribution. Mean (range) injected activities were 324 (236–424) MBq versus 345 (235–420) MBq, and acquisition times were 84 (42–166) versus 76 (59–122) minutes for 18F-rhPSMA-7 versus 18F-rhPSMA-7.3, respectively. SUVmean was determined for background (gluteal muscle), normal organs (salivary glands, blood pool, lung, liver, spleen, pancreas, duodenum, kidney, bladder, bone) and up to three representative tumour lesions. Qualitative analyses assessed image quality, non-specific blood pool activity, and background uptake in bone/marrow using 3/4-point scales. Results Preclinical dosimetry revealed that at 3.5 h and 1 h bladder voiding intervals, the extrapolated total effective doses were 26.6 and 12.2 µSv/MBq for 18F-rhPSMA-7 and 21.7 and 12.8 µSv/MBq for 18F-rhPSMA-7.3 respectively. Human biodistribution of both agents was typical of other PSMA-ligands and broadly similar to each other; SUVmean were 16.9 versus 16.2 (parotid gland), 19.6 versus 19.9 (submandibular gland), 2.0 versus 1.9 (blood pool, p < 0.005), 0.7 versus 0.7 (lungs), 7.0 versus 7.3 (liver), 9.1 versus 8.4 (spleen), 32.4 versus 35.7 (kidney), 2.5 versus 2.8 (pancreas), 10.9 versus 11.0 (duodenum), 1.1 versus 1.3 (bone) and 4.6 versus 2.0 (bladder; p < 0.001) for 18F-rhPSMA-7 versus 18F-rhPSMA-7.3, respectively. Tumour SUVmean was higher for 18F-rhPSMA-7.3 (32.5 ± 42.7, n = 63 lesions) than for 18F-rhPSMA-7 (20.0 ± 20.2, n = 89 lesions). Conclusions Radiation dosimetry is favourable for both agents. Radiation exposure, assuming a 1 h voiding interval, is less than 5 mSv after injection of 370 MBq. 18F-rhPSMA-7.3 showed significantly lower bladder uptake, and a higher uptake trend in tumours compared with 18F-rhPSMA-7. Supplementary Information The online version contains supplementary material available at 10.1186/s13550-021-00872-w.
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Affiliation(s)
- Karina Knorr
- School of Medicine, Klinikum Rechts der Isar, Department of Nuclear Medicine, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany.
| | - So Won Oh
- School of Medicine, Klinikum Rechts der Isar, Department of Nuclear Medicine, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany.,Department of Nuclear Medicine, Seoul National University Boramae Medical Center, Seoul, Korea
| | - Markus Krönke
- School of Medicine, Klinikum Rechts der Isar, Department of Nuclear Medicine, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany.,School of Medicine, Klinikum Rechts der Isar, Department of Diagnostic and Interventional Radiology, Technical University of Munich, Munich, Germany
| | | | - Calogero D'Alessandria
- School of Medicine, Klinikum Rechts der Isar, Department of Nuclear Medicine, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany
| | - Michael Herz
- School of Medicine, Klinikum Rechts der Isar, Department of Nuclear Medicine, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany
| | - Wolfgang Weber
- School of Medicine, Klinikum Rechts der Isar, Department of Nuclear Medicine, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany
| | | | - Matthias Eiber
- School of Medicine, Klinikum Rechts der Isar, Department of Nuclear Medicine, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany
| | - Nahid Yusufi
- School of Medicine, Klinikum Rechts der Isar, Department of Nuclear Medicine, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany
| | - Stephan Nekolla
- School of Medicine, Klinikum Rechts der Isar, Department of Nuclear Medicine, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany
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Wurzer A, Kunert JP, Fischer S, Felber V, Beck R, De Rose F, D'Alessandria C, Weber WA, Wester HJ. Synthesis and Preclinical Evaluation of 177Lu-labeled Radiohybrid PSMA Ligands (rhPSMAs) for Endoradiotherapy of Prostate Cancer. J Nucl Med 2022; 63:1489-1495. [PMID: 35086894 PMCID: PMC9536713 DOI: 10.2967/jnumed.121.263371] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [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: 10/12/2021] [Accepted: 01/18/2022] [Indexed: 11/16/2022] Open
Abstract
INTRODUCTION The prostate-specific membrane antigen (PSMA)-targeted radiohybrid (rh) ligand [177Lu]Lu-rhPSMA-7.3 has recently been assessed in a pretherapeutic dosimetry study in prostate cancer patients. In comparison to [177Lu]Lu-PSMA I&T, application of [177Lu]Lu-rhPSMA-7.3 resulted in a significantly improved tumor dose, but also higher kidney accumulation. AIM Although rhPSMA-7.3 has been initially selected as the lead compound for diagnostic application based on the characterization of its gallium complex, a systematic comparison of the most promising 177Lu-labeled rhPSMA ligands is still missing. Thus, this study aimed to identify the rhPSMA ligand with most favorable pharmacokinetics for 177Lu-radioligand therapy. Methods: The four isomers of [177Lu]Lu-rhPSMA-7 (namely [177Lu]Lu-rhPSMA-7.1, -7.2, -7.3 and -7.4), along with the novel radiohybrid ligands [177Lu]Lu-rhPSMA-10.1 and -10.2, were compared to the state-of-the-art compounds [177Lu]Lu-PSMA I&T and [177Lu]Lu-PSMA-617. The comparative evaluation comprised affinity studies (IC50) and internalization experiments on LNCaP cells, as well as lipophilicity measurements. In addition, we determined the apparent molecular weight (AMW) of each tracer as a parameter for human serum albumin (HSA) binding. Biodistribution studies and µSPECT imaging was performed in LNCaP-tumor bearing mice at 24 h post injection. Results: 177Lu-labeling of the radiohybrids was carried out according to the established procedures for the currently established PSMA-targeted ligands. All ligands showed potent binding to PSMA-expressing LNCaP cells, with affinities in the low nanomolar range and high internalization rates. Surprisingly, most pronounced differences were identified regarding the HSA-related AMW. While [177Lu]Lu-rhPSMA-7 isomers demonstrated the highest AMW and thus strongest HSA-interactions, [177Lu]Lu-rhPSMA-10.1 showed an AMW lower than [177Lu]Lu-rhPSMA-7.3 but higher than the 177Lu-labeled references PSMA I&T and PSMA-617. In biodistribution studies [177Lu]Lu-rhPSMA-10.1 exhibited the lowest kidney uptake and fastest excretion from the blood pool of all rhPSMA ligands, while preserving a high tumor accumulation. Conclusion: Clinical investigation of [177Lu]Lu-rhPSMA-10.1 is highly warranted in order to determine if the favorable pharmacokinetics observed in mice will also result in high tumor uptake and decreased absorbed dose to kidneys and other non-target tissues in patients.
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Langbein T, Wang H, Rauscher I, Krönke M, Knorr K, Wurzer A, Schwamborn K, Maurer T, Horn T, Haller B, Wester HJ, Eiber M. Utility of 18F-rhPSMA-7.3 positron emission tomography for imaging of primary prostate cancer and pre-operative efficacy in N-staging of unfavorable intermediate to very high-risk patients validated by histopathology. J Nucl Med 2022; 63:1334-1342. [PMID: 34992154 DOI: 10.2967/jnumed.121.263440] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [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: 10/26/2021] [Revised: 12/28/2021] [Indexed: 11/16/2022] Open
Abstract
18F-rhPSMA-7.3, the lead compound of a new class of radiohybrid prostate-specific membrane antigen (rhPSMA) ligands, is currently in phase III trials for prostate cancer (PCa) imaging. Here, we describe our experience in primary PCa staging. Methods: We retrospectively identified 279 patients with primary PCa who underwent 18F-rhPSMA-7.3 PET/CT (staging cohort). A subset of patients (83/279) subsequently underwent prostatectomy with lymph node (LN) dissection without prior treatment (efficacy cohort). Distribution of tumor lesions was determined for the staging cohort and stratified by National Comprehensive Cancer Network (NCCN) risk score. Involvement of pelvic LN was assessed retrospectively by 3 blinded independent central readers, and a majority rule was used for analysis. Standard surgical fields were rated on a five-point scale independently for PET and for morphological imaging. Results were compared to histopathological findings on a patient-, right vs. -left, and template-basis. Results: For the staging cohort 18F-rhPSMA-7.3 PET was positive in 275/279 (98.6%), 106/279 (38.0%), 46/279 (16.5%), 65/279 (23.3%) and 5/279 (1.8%) patients for local, pelvic nodal, extrapelvic nodal, metastatic bone, and visceral metastatic disease. In the efficacy cohort, LN metastases were present in 24/83 patients (29%), located in 48/420 (11%) resected templates and in 33/166 (19.9%) hemi-pelvic templates in histopathology. Based on majority vote results, the patient-level sensitivity, specificity and accuracy for pelvic nodal metastases were 66.7% (95%CI, 44.7-83.6%), 96.6% (95%CI, 87.3-99.4%) and 88.0% (95%CI, 78.5-93.8%) for 18F-rhPSMA-7.3 PET and 37.5% (95%CI, 19.6-59.2%), 91.5% (95%CI, 80.6-96.8%) and 75.9% (95%CI, 65.0-84.3%) for morphological imaging, respectively. 18F-rhPSMA-7.3 showed higher interobserver agreement than morphological imaging (patient-level Fleiss' κ=0.54; 95%CI, 0.47-0.62 vs. 0.24; 95%CI, 0.17-0.31). A mean standardized uptake value ratio of 6.6 (95%CI, 5.2-8.1) documented a high image contrast between local tumors and adjacent low urinary tracer retention. Conclusion: 18F-rhPSMA-7.3 PET offers superior diagnostic performance to morphological imaging for primary N-staging of newly diagnosed PCa, shows lower inter-reader variation, and offers good distinction between primary tumor and bladder background activity. With increasing NCCN risk group an increasing frequency of extra-prostatic tumor lesions was observed.
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Affiliation(s)
- Thomas Langbein
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Nuclear Medicine, Germany
| | - Hui Wang
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Nuclear Medicine, Germany
| | - Isabel Rauscher
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Nuclear Medicine, Germany
| | - Markus Krönke
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Nuclear Medicine, Germany
| | - Karina Knorr
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Nuclear Medicine, Germany
| | | | - Kristina Schwamborn
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Institute of Pathology, Germany
| | - Tobias Maurer
- Martini-Klinik and Department of Urology, University Hospital Hamburg-Eppendorf, Germany
| | - Thomas Horn
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Urology, Germany
| | - Bernhard Haller
- Technical University of Munich, School of Medicine, Institute of Medical Informatics, Statistics and Epidemiology, Germany
| | | | - Matthias Eiber
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Nuclear Medicine, Germany
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8
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Langbein T, Wurzer A, Gafita A, Robertson A, Wang H, Arcay A, Herz M, Wester HJ, Weber WA, Eiber M. The Influence of Specific Activity on the Biodistribution of 18F-rhPSMA-7.3: A Retrospective Analysis of Clinical Positron Emission Tomography Data. J Nucl Med 2021; 63:742-745. [PMID: 34385338 DOI: 10.2967/jnumed.121.262471] [Citation(s) in RCA: 4] [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: 04/25/2021] [Revised: 08/05/2021] [Indexed: 11/16/2022] Open
Abstract
We investigated whether the time between synthesis and injection and the resulting decrease in specific activity affects the normal organ and tumor uptake of the PSMA ligand, 18F-rhPSMA-7.3, in patients with prostate cancer. Methods: The biodistribution of 18F-rhPSMA-7.3 on PET/CT scans performed with a high specific activity (median = 178.9MBq/µg, n = 42) and a low specific activity (median = 19.3MBq/µg, n = 42) were compared. Results: Tracer uptake by the parotid gland, submandibular gland and spleen was moderately, but significantly lower in the "low specific activity" group than in the "high specific activity" group (median SUVmean 16.7 vs. 19.2; 18.1 vs. 22.3, and 7.8 vs. 9.6, respectively). No other statistically significant differences were found for normal organs or tumor lesions. Conclusion: A 10-fold decrease in specific activity has only minor effects on the biodistribution of 18F-rhPSMA-7.3. These findings suggest that 18F-labeled PSMA ligands can be centrally produced and shipped to PET clinics in a similar way to 18F-fluorodeoxyglucose.
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Affiliation(s)
- Thomas Langbein
- Technical University of Munich, Klinikum rechts der Isar, Germany
| | | | - Andrei Gafita
- Ahmanson Translational Theranostics Division, Department of Molecular & Medical Pharmacology, University of California
| | - Andrew Robertson
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Nuclear Medicine, Germany
| | - Hui Wang
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Nuclear Medicine, Germany
| | - Ayca Arcay
- Akdeniz University, Department of Nuclear Medicine, Turkey
| | - Michael Herz
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Nuclear Medicine, Germany
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Yusufi N, Wurzer A, Herz M, D'Alessandria C, Feuerecker B, Weber W, Wester HJ, Nekolla S, Eiber M. Comparative Preclinical Biodistribution, Dosimetry, and Endoradiotherapy in Metastatic Castration-Resistant Prostate Cancer Using 19F/ 177Lu-rhPSMA-7.3 and 177Lu-PSMA I&T. J Nucl Med 2021; 62:1106-1111. [PMID: 33443072 DOI: 10.2967/jnumed.120.254516] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [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: 08/10/2020] [Accepted: 12/04/2020] [Indexed: 12/29/2022] Open
Abstract
Radiohybrid prostate-specific membrane antigen (rhPSMA) ligands are applicable as radiochemical twins for both diagnostic PET imaging and endoradiotherapy. On the basis of preliminary data as a diagnostic ligand, the isomer rhPSMA-7.3 is a promising candidate for potential endoradiotherapy. The aim of this preclinical evaluation was to assess the biodistribution, dosimetry, and therapeutic efficacy of 19F/177Lu-rhPSMA-7.3 in comparison to the established therapeutic agent 177Lu-PSMA I&T (imaging and therapy). Methods: The biodistribution of 19F/177Lu-rhPSMA-7.3 and 177Lu-PSMA I&T was determined in LNCaP tumor-bearing severe combined immunodeficiency (SCID) mice after sacrifice at defined time points up to 7 d (n = 5). Organs and tumors were dissected, percentage injected dose per gram (%ID/g) was determined, and dosimetry was calculated using OLINDA/EXM, version 1.0. The therapeutic efficacy of a single 30-MBq dose of 19F/177Lu-rhPSMA-7.3 (n = 7) was compared with that of 177Lu-PSMA I&T in treatment groups (n = 7) and control groups (n = 6-7) using C4-2 tumor-bearing SCID mice by evaluating tumor growth and survival over 6 wk after treatment. Results: The biodistribution of 19F/177Lu-rhPSMA-7.3 revealed fast blood clearance (0.63 %ID/g at 1 h after injection), and the highest activity uptake was in the spleen and kidneys, particularly in the first hour (33.25 %ID/g and 207.6 %ID/g, respectively, at 1 h after injection), indicating a renal excretion pathway. Compared with 177Lu-PSMA I&T, 19F/177Lu-rhPSMA-7.3 exhibited an initial (1 h) 2.6-fold higher tumor uptake in LNCaP xenografts and a longer retention (4.5 %ID/g vs. 0.9 %ID/g at 168 h). The tumor dose of 19F/177Lu-rhPSMA-7.3 was substantially higher (e.g., 7.47 vs. 1.96 µGy/MBq at 200 mm3) than that of 177Lu-PSMA I&T. In most organs, absorbed doses were higher for 177Lu-PSMA I&T. A significantly greater tumor size reduction was shown for a single dose of 19F/177Lu-rhPSMA-7.3 than for 177Lu-PSMA I&T at the end of the experiment (P = 0.0167). At the predefined termination of the experiment at 6 wk, 7 of 7 and 3 of 7 mice were still alive in the 19F/177Lu-rhPSMA-7.3 and 177Lu-PSMA I&T groups, respectively, compared with the respective control groups, with 0 of 7 and 0 of 6 mice. Conclusion: Compared with 177Lu-PSMA I&T, 19F/177Lu-rhPSMA-7.3 can be considered a suitable candidate for clinical translation because it has similar clearance kinetics and a similar radiation dose to healthy organs but superior tumor uptake and retention. Preliminary treatment experiments showed a favorable antitumor response.
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Affiliation(s)
- Nahid Yusufi
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany; and
| | - Alexander Wurzer
- Chair for Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany
| | - Michael Herz
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany; and
| | - Calogero D'Alessandria
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany; and
| | - Benedikt Feuerecker
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany; and
| | - Wolfgang Weber
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany; and
| | - Hans-Jürgen Wester
- Chair for Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany
| | - Stephan Nekolla
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany; and
| | - Matthias Eiber
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany; and
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10
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Chantadisai M, Buschner G, Krönke M, Rauscher I, Langbein T, Nekolla SG, Schiller K, Heck MM, Maurer T, Wurzer A, Wester HJ, D'Alessandria C, Weber W, Eiber M. Positive Predictive Value and Correct Detection Rate of 18F-rhPSMA-7 PET in Biochemically Recurrent Prostate Cancer Validated by Composite Reference Standard. J Nucl Med 2021; 62:968-974. [PMID: 33188151 DOI: 10.2967/jnumed.120.255661] [Citation(s) in RCA: 2] [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: 08/24/2020] [Revised: 10/19/2020] [Indexed: 11/16/2022] Open
Abstract
The objective of this retrospective study was to assess the detection rate (DR), positive predictive value (PPV), and correct detection rate (CDR) of 18F-rhPSMA-7 PET/CT in biochemical recurrence (BCR) of prostate cancer (PCa) after radical prostatectomy (RP) using composite validation. Methods: 18F-rhPSMA-7 PET/CT scans of patients with BCR between July 2017 and June 2018 were retrospectively reviewed. All suspicious lesions were recorded. The reference standard was histopathology or combinations of histopathology, imaging, or prostate-specific antigen (PSA) follow up, defined as composite reference standard. DR was calculated as the proportion of PSMA PET-positive patients to all patients independent of the reference standard, whereas the CDR was the percentage of patients who had at least 1 true-positive PSMA PET lesion localized that corresponded with the reference standard. The PPV was defined as the proportion of patients who had true-positive to all positive findings. The correlation between DR and patient characteristics was evaluated. Results: A total of 532 patients with a median PSA level of 0.97 ng/mL (interquartile range: 0.41-2.46 ng/mL) were included. Of these, 162 patients had composite follow-up at a median duration of 5.6 mo (range: 1.1-14.2 mo). The proportion of patients who had no lesion visualized on PET/CT, localized disease, and any distant metastases (M1) were 20%, 43%, and 37%, respectively. PET DR among all patients was 80%. On a per-patient basis, the PPV of 18F-rhPSMA-7 PET/CT in the composite cohort was 88%, and the CDR was 70%. The PPV in the histopathology-proven cohort was 91%, and the CDR in this subgroup was 73%. In patients with PSA levels ≥ 1 ng/mL the DR and PPV were 90% and 91%, respectively, resulting in a CDR of 82%. In patients with PSA levels < 1 ng/mL, the DR and PPV were 69% and 85%, respectively, resulting in a CDR of 59%. There was a significant positive correlation between 18F-rhPSMA-7 PET/CT detection efficacy and stratified PSA levels (P = 0.005), as well as PSA nadir after prostatectomy (P < 0.001). Conclusion: 18F-rhPSMA-7 PET/CT offers high PPV in BCR after RP. Its CDR is dependent on the prescan PSA value with excellent CDR in patients with PSA ≥ 1 ng/mL.
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Affiliation(s)
- Maythinee Chantadisai
- School of Medicine, Department of Nuclear Medicine, Technical University Munich, Munich, Germany; .,Division of Nuclear Medicine, Department of Radiology, Faculty of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand
| | - Gabriel Buschner
- School of Medicine, Department of Nuclear Medicine, Technical University Munich, Munich, Germany
| | - Markus Krönke
- School of Medicine, Department of Nuclear Medicine, Technical University Munich, Munich, Germany
| | - Isabel Rauscher
- School of Medicine, Department of Nuclear Medicine, Technical University Munich, Munich, Germany
| | - Thomas Langbein
- School of Medicine, Department of Nuclear Medicine, Technical University Munich, Munich, Germany
| | - Stephan G Nekolla
- School of Medicine, Department of Nuclear Medicine, Technical University Munich, Munich, Germany
| | - Kilian Schiller
- School of Medicine, Department of Radiation Oncology, Technical University Munich, Munich, Germany
| | - Matthias M Heck
- School of Medicine, Department of Urology, Technical University Munich, Munich, Germany
| | - Tobias Maurer
- School of Medicine, Department of Urology, Technical University Munich, Munich, Germany.,Martini-Klinik and Department of Urology, University Hospital Hamburg-Eppendorf, Hamburg, Germany; and
| | | | | | - Calogero D'Alessandria
- School of Medicine, Department of Nuclear Medicine, Technical University Munich, Munich, Germany
| | - Wolfgang Weber
- School of Medicine, Department of Nuclear Medicine, Technical University Munich, Munich, Germany
| | - Matthias Eiber
- School of Medicine, Department of Nuclear Medicine, Technical University Munich, Munich, Germany
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11
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Wurzer A, Parzinger M, Konrad M, Beck R, Günther T, Felber V, Färber S, Di Carlo D, Wester HJ. Preclinical comparison of four [ 18F, natGa]rhPSMA-7 isomers: influence of the stereoconfiguration on pharmacokinetics. EJNMMI Res 2020; 10:149. [PMID: 33284394 PMCID: PMC7721954 DOI: 10.1186/s13550-020-00740-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 11/24/2020] [Indexed: 12/27/2022] Open
Abstract
Introduction Radiohybrid (rh) ligands, a novel class of prostate-specific membrane antigen (PSMA)-targeted radiopharmaceuticals, can be labeled either with [18F]fluorine via isotopic exchange or with radiometals (such as [68Ga]Gallium, [177Lu]Lutetium, [225Ac]Actinium). Among these, [18F, natGa]rhPSMA-7 has recently entered clinical assessment.
Aim Since [18F, natGa]rhPSMA-7 is composed of four stereoisomers ([18F, natGa]rhPSMA-7.1, -7.2, -7.3 and -7.4), we initiated a preclinical selection process to identify the isomer with the most favorable pharmacokinetics for further clinical investigation. Methods A synthetic protocol for enantiopure [19F, natGa]rhPSMA-7 isomers has been developed. The comparative evaluation of the four isomers comprised human serum albumin binding, lipophilicity, IC50, internalization and classical biodistribution studies and competition experiments in LNCaP tumor-bearing CB-17 SCID mice. In addition, a radio high-performance liquid chromatography-based method was developed allowing quantitative, intraindividual comparison of [18F, natGa]rhPSMA-7.1 to -7.4 in LNCaP tumor-bearing mice. Results Cell studies revealed high PSMA affinity and internalization for [18/19F, natGa]rhPSMA-7.2, -7.3 and -7.4, whereas [18/19F, natGa]rhPSMA-7.1 showed approximately twofold lower values. Although the biodistribution profile obtained was typical of PSMA inhibitors, it did not allow for selection of a lead candidate for clinical studies. Thus, an intraindividual comparison of all four isomers in LNCaP tumor-bearing mice was carried out by injection of a diastereomeric mixture, followed by analysis of the differential uptake and excretion pattern of each isomer. Based on its high tumor accumulation and low uptake in blood, liver and kidneys, [18F, natGa]rhPSMA-7.3 was identified as the preferred isomer and transferred into clinical studies. Conclusion [18F, natGa]rhPSMA-7.3 has been selected as a lead compound for clinical development of a [18F]rhPSMA-based candidate. The intraindividual differential uptake and excretion analysis in vivo allowed for an accurate comparison and assessment of radiopharmaceuticals.
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Affiliation(s)
- Alexander Wurzer
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Walther-Meißner-Str. 3, 85748, Garching, Germany.
| | - Mara Parzinger
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Walther-Meißner-Str. 3, 85748, Garching, Germany
| | - Matthias Konrad
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Walther-Meißner-Str. 3, 85748, Garching, Germany
| | - Roswitha Beck
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Walther-Meißner-Str. 3, 85748, Garching, Germany
| | - Thomas Günther
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Walther-Meißner-Str. 3, 85748, Garching, Germany
| | - Veronika Felber
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Walther-Meißner-Str. 3, 85748, Garching, Germany
| | - Stefanie Färber
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Walther-Meißner-Str. 3, 85748, Garching, Germany
| | - Daniel Di Carlo
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Walther-Meißner-Str. 3, 85748, Garching, Germany
| | - Hans-Jürgen Wester
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Walther-Meißner-Str. 3, 85748, Garching, Germany
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12
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Kroenke M, Mirzoyan L, Horn T, Peeken JC, Wurzer A, Wester HJ, Makowski M, Weber WA, Eiber M, Rauscher I. Matched-Pair Comparison of 68Ga-PSMA-11 and 18F-rhPSMA-7 PET/CT in Patients with Primary and Biochemical Recurrence of Prostate Cancer: Frequency of Non-Tumor-Related Uptake and Tumor Positivity. J Nucl Med 2020; 62:1082-1088. [PMID: 33277394 DOI: 10.2967/jnumed.120.251447] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [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: 06/11/2020] [Accepted: 11/12/2020] [Indexed: 11/16/2022] Open
Abstract
Radiohybrid prostate-specific membrane antigen (rhPSMA) ligands are a new class of prostate cancer theranostic agents. 18F-rhPSMA-7 offers the advantages of 18F labeling and low urinary excretion compared with 68Ga-PSMA-11. Here, we compare the frequency of non-tumor-related uptake and tumor positivity with 68Ga-PSMA-11 and 18F-rhPSMA-7 in patients with primary or recurrent prostate cancer. Methods: This retrospective matched-pair comparison matched 160 18F-rhPSMA-7 with 160 68Ga-PSMA-11 PET/CT studies for primary staging (n = 33) and biochemical recurrence (n = 127) according to clinical characteristics. Two nuclear medicine physicians reviewed all scans, first identifying all PET-positive lesions and then differentiating lesions suggestive of prostate cancer from those that were benign, on the basis of known pitfalls and ancillary information from CT. For each region, the SUVmax of the lesion with the highest PSMA ligand uptake was noted. Tumor positivity rates were determined, and SUVmax was compared separately for each tracer. Results: 18F-rhPSMA-7 and 68Ga-PSMA-11 PET revealed 566 and 289 PSMA ligand-positive lesions, respectively. Of these, 379 and 100 lesions, equaling 67.0% and 34.6%, respectively, of all PSMA-positive lesions, were considered benign. The distribution of their etiology was similar (42%, 24%, and 25% with 18F-rhPSMA-7 vs. 32%, 24%, and 38% with 68Ga-PSMA-11 for ganglia, bone, and unspecific lymph nodes, respectively). All primary tumors were positive with both agents (n = 33 each), whereas slightly more metastatic lesions were observed with 68Ga-PSMA-11 in both disease stages (113 for 18F-rhPSMA-7 and 124 for 68Ga-PSMA-11). The SUVmax of 18F-rhPSMA-7 and 68Ga-PSMA-11 did not differ (P > 0.05) in local recurrence or primary prostate cancer; however, the tumor-to-bladder ratio was significantly higher with 18F-rhPSMA-7 (4.9 ± 5.3 vs. 2.2 ± 3.7, P = 0.02, for local recurrence; 9.8 ± 9.7 vs. 2.3 ± 2.6, P < 0.001, for primary prostate cancer). Conclusion: The tumor positivity rate was consistently high for 68Ga-PSMA-11 and 18F-rhPSMA-7. Both tracers revealed a considerable number of areas of uptake that were reliably identified as benign by trained physicians making use of corresponding morphologic imaging and known PSMA pitfalls. These were more frequent with 18F-rhPSMA-7. However, the matched-pair comparison could have introduced a source of bias. Adequate reader training can allow physicians to differentiate benign uptake from disease and be able to benefit from the logistical and clinical advantages of 18F-rhPSMA-7.
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Affiliation(s)
- Markus Kroenke
- Institute of Diagnostic and Interventional Radiology, School of Medicine, Technical University of Munich, Munich, Germany.,Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany
| | - Lilit Mirzoyan
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany
| | - Thomas Horn
- Department of Urology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Jan C Peeken
- Department of Radiation Oncology, School of Medicine, Technical University of Munich, Munich, Germany.,Institute of Radiation Medicine, Department of Radiation Sciences, Helmholtz Zentrum München, Neuherberg, Germany; and
| | - Alexander Wurzer
- Pharmaceutical Radiochemistry, School of Medicine, Technical University of Munich. Munich, Germany
| | - Hans-Jürgen Wester
- Pharmaceutical Radiochemistry, School of Medicine, Technical University of Munich. Munich, Germany
| | - Marcus Makowski
- Institute of Diagnostic and Interventional Radiology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Wolfgang A Weber
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany
| | - Matthias Eiber
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany
| | - Isabel Rauscher
- Department of Nuclear Medicine, School of Medicine, Technical University of Munich, Munich, Germany;
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Wurzer A, Di Carlo D, Schmidt A, Beck R, Eiber M, Schwaiger M, Wester HJ. Radiohybrid Ligands: A Novel Tracer Concept Exemplified by 18F- or 68Ga-Labeled rhPSMA Inhibitors. J Nucl Med 2020; 61:735-742. [PMID: 31862804 PMCID: PMC7198388 DOI: 10.2967/jnumed.119.234922] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 09/27/2019] [Indexed: 11/16/2022] Open
Abstract
When we critically assess the reason for the current dominance of 68Ga-labeled peptides and peptide-like ligands in radiopharmacy and nuclear medicine, we have to conclude that the major advantage of such radiopharmaceuticals is the apparent lack of suitable 18F-labeling technologies with proven clinical relevance. To prepare and to subsequently perform a clinical proof-of-concept study on the general suitability of silicon-fluoride-acceptor (SiFA)-conjugated radiopharmaceuticals, we developed inhibitors of the prostate-specific membrane antigen (PSMA) that are labeled by isotopic exchange (IE). To compensate for the pronounced lipophilicity of the SiFA unit, we used metal chelates, conjugated in close proximity to SiFA. Six different radiohybrid PSMA ligands (rhPSMA ligands) were evaluated and compared with the commonly used 18F-PSMA inhibitors 18F-DCFPyL and 18F-PSMA-1007. Methods: All inhibitors were synthesized by solid-phase peptide synthesis. Human serum albumin binding was measured by affinity high-performance liquid chromatography, whereas the lipophilicity of each tracer was determined by the n-octanol/buffer method. In vitro studies (IC50, internalization) were performed on LNCaP cells. Biodistribution studies were conducted on LNCaP tumor-bearing male CB-17 SCID mice. Results: On the laboratory scale (starting activities, 0.2-9.0 GBq), labeling of 18F-rhPSMA-5 to -10 by IE was completed in < 20 min (radiochemical yields, 58% ± 9%; radiochemical purity, >97%) with molar activities of 12-60 GBq/μmol. All rhPSMAs showed low nanomolar affinity and high internalization by PSMA-expressing cells when compared with the reference radiopharmaceuticals, medium-to-low lipophilicity, and high human serum albumin binding. Biodistribution studies in LNCaP tumor-bearing mice revealed high tumor uptake, sufficiently fast clearance kinetics from blood, low hepatobiliary excretion, fast renal excretion, and very low uptake of 18F activity in bone. Conclusion: The novel 18F-rhPSMA radiopharmaceuticals developed under the radiohybrid concept show equal or better targeting characteristics than the established 18F-PSMA tracers 18F-DCFPyL and 18F-PSMA-1007. The unparalleled simplicity of production, the possibility to produce the identical 68Ga-labeled 19F-68Ga-rhPSMA tracers, and the possibility to extend this concept to true theranostic radiohybrid radiopharmaceuticals, such as F-Lu-rhPSMA, are unique features of these radiopharmaceuticals.
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Affiliation(s)
- Alexander Wurzer
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany; and
| | - Daniel Di Carlo
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany; and
| | - Alexander Schmidt
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany; and
| | - Roswitha Beck
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany; and
| | - Matthias Eiber
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Markus Schwaiger
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Hans-Jürgen Wester
- Chair of Pharmaceutical Radiochemistry, Technical University of Munich, Garching, Germany; and
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Oh SW, Wurzer A, Teoh EJ, Oh S, Langbein T, Krönke M, Herz M, Kropf S, Wester HJ, Weber WA, Eiber M. Quantitative and Qualitative Analyses of Biodistribution and PET Image Quality of a Novel Radiohybrid PSMA, 18F-rhPSMA-7, in Patients with Prostate Cancer. J Nucl Med 2019; 61:702-709. [PMID: 31836686 DOI: 10.2967/jnumed.119.234609] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [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: 08/08/2019] [Accepted: 11/11/2019] [Indexed: 11/16/2022] Open
Abstract
Radiohybrid PSMA (rhPSMA) ligands, a new class of theranostic prostate-specific membrane antigen (PSMA)-targeting agents, feature fast 18F synthesis and utility for labeling with radiometals. Here, we assessed the biodistribution and image quality of 18F-rhPSMA-7 to determine the best imaging time point for patients with prostate cancer. Methods: In total, 202 prostate cancer patients who underwent a clinically indicated 18F-rhPSMA-7 PET/CT were retrospectively analyzed, and 12 groups based on the administered activity and uptake time of PET scanning were created: 3 administered activities (low, 222-296 MBq; moderate, 297-370 MBq; and high, 371-444 MBq) and 4 uptake time points (short, 50-70 min; intermediate, 71-90 min; long, 91-110 min; and extra long, ≥111 min). For quantitative analyses, SUVmean and organ- or tumor-to-background ratio were determined for background, healthy organs, and 3 representative tumor lesions. Qualitative analyses assessed overall image quality, nonspecific blood-pool activity, and background uptake in bone or marrow using 3- or 4-point scales. Results: In quantitative analyses, SUVmean showed a significant decrease in the blood pool and lungs and an increase in the kidneys, bladder, and bones as the uptake time increased. SUVmean showed a trend to increase in the blood pool and bones as the administered activity increased. However, no significant differences were found in 377 tumor lesions with respect to the administered activity or uptake time. In qualitative analyses, the overall image quality was stable along with the uptake time, but the proportion rated to have good image quality decreased as the administered activity increased. All other qualitative image parameters showed no significant differences for the administered activities, but they showed significant trends with increasing uptake time: less nonspecific blood activity, more frequent background uptake in the bone marrow, and increased negative impact on clinical decision making. Conclusion: The biodistribution of 18F-rhPSMA-7 was similar to that of established PSMA ligands, and tumor uptake of 18F-rhPSMA-7 was stable across the administered activities and uptake times. An early imaging time point (50-70 min) is recommended for 18F-rhPSMA-7 PET/CT to achieve the highest overall image quality.
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Affiliation(s)
- So Won Oh
- Department of Nuclear Medicine, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.,Department of Nuclear Medicine, Seoul National University Boramae Medical Center, Seoul, Korea
| | | | - Eugene J Teoh
- Department of Radiology and Nuclear Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Sohee Oh
- Department of Biostatistics, Seoul National University Boramae Medical Center, Seoul, Korea; and
| | - Thomas Langbein
- Department of Nuclear Medicine, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Markus Krönke
- Department of Nuclear Medicine, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Michael Herz
- Department of Nuclear Medicine, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | | | | | - Wolfgang A Weber
- Department of Nuclear Medicine, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Matthias Eiber
- Department of Nuclear Medicine, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
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Eiber M, Kroenke M, Wurzer A, Ulbrich L, Jooß L, Maurer T, Horn T, Schiller K, Langbein T, Buschner G, Wester HJ, Weber W. 18F-rhPSMA-7 PET for the Detection of Biochemical Recurrence of Prostate Cancer After Radical Prostatectomy. J Nucl Med 2019; 61:696-701. [PMID: 31836682 DOI: 10.2967/jnumed.119.234914] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [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: 08/08/2019] [Accepted: 10/30/2019] [Indexed: 02/06/2023] Open
Abstract
18F-labeled prostate-specific membrane antigen (PSMA) PET tracers are increasingly used in preference to 68Ga-PSMA-11 for restaging biochemical recurrence (BCR) of prostate cancer. They are associated with longer half-lives, larger-scale production, and lower positron range than their 68Ga-labeled counterparts. Here, we describe the efficacy of an 18F-labeled radiohybrid PSMA, rhPSMA-7, a novel theranostic PSMA-targeting agent for imaging BCR of prostate cancer. Methods: Datasets from 261 consecutive patients with noncastrate BCR after radical prostatectomy who underwent 18F-rhPSMA-7 PET/CT at our institution between June 2017 and March 2018 were reviewed retrospectively. All lesions suspected of being recurrent prostate cancer were recorded. The detection rate for sites of presumed recurrence was correlated with patients' prostate-specific antigen (PSA) level, primary Gleason score, and prior therapy (androgen deprivation therapy and external-beam radiation therapy). Results: The 261 patients had a median PSA level of 0.96 ng/mL (range, 0.01-400 ng/mL). The median injected activity of 18F-rhPSMA-7 was 336 MBq, with a median uptake time of 76 min. In total, 211 patients (81%) showed pathologic findings on 18F-rhPSMA-7 PET/CT. The detection rates were 71% (42/59), 86% (44/51), 86% (42/49), and 95% (76/80) at PSA levels of 0.2 to <0.5 ng/mL, 0.5 to <1 ng/mL, 1 to <2 ng/mL, and ≥2 ng/mL, respectively. In 32% patients (7/22) with a PSA of less than 0.2 ng/mL, suggestive lesions were present. 18F-rhPSMA-7 PET/CT revealed local recurrence in 43% of patients (113). Lymph node metastases were present in the pelvis in 42% of patients (110), in the retroperitoneum in 17% (45), and in a supradiaphragmatic location in 8.0% (21). Bone and visceral metastases were detected in 21% (54) and 3.8% (10), respectively. Detection efficacy was not influenced by prior external-beam radiation therapy (79.1% vs. 82.1%, P = 0.55), androgen deprivation therapy within the 6 mo preceding imaging (80.6% vs. 80.9%, P = 0.54), or primary Gleason score (77.9% for ≤7 vs. 82.6% for ≥8, P = 0.38). Conclusion: 18F-rhPSMA-7 PET/CT offers high detection rates in early BCR after radical prostatectomy, especially among patients with low PSA values.
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Affiliation(s)
- Matthias Eiber
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Markus Kroenke
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Alexander Wurzer
- Chair of Radiopharmacy, Technical University of Munich, Munich, Germany
| | - Lena Ulbrich
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Lena Jooß
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Tobias Maurer
- Department of Urology and Martini-Klinik, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Thomas Horn
- Department of Urology, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany; and
| | - Kilian Schiller
- Department of Radiation Oncology, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Thomas Langbein
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Gabriel Buschner
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | | | - Wolfgang Weber
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
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Kroenke M, Wurzer A, Schwamborn K, Ulbrich L, Jooß L, Maurer T, Horn T, Rauscher I, Haller B, Herz M, Wester HJ, Weber WA, Eiber M. Histologically Confirmed Diagnostic Efficacy of 18F-rhPSMA-7 PET for N-Staging of Patients with Primary High-Risk Prostate Cancer. J Nucl Med 2019; 61:710-715. [PMID: 31836681 DOI: 10.2967/jnumed.119.234906] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [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: 08/08/2019] [Accepted: 12/03/2019] [Indexed: 01/06/2023] Open
Abstract
18F-rhPSMA-7 (radiohybrid prostate-specific membrane antigen [PSMA]) is a novel ligand for PET imaging. Here, we present data from a retrospective analysis using PET/CT and PET/MRI examinations to investigate the efficacy of 18F-rhPSMA-7 PET for primary N-staging of patients with prostate cancer (PC) compared with morphologic imaging (CT or MRI) and validated by histopathology. Methods: Data from 58 patients with high-risk PC (according to the D'Amico criteria) who were staged with 18F-rhPSMA-7 PET/CT or PET/MRI at our institution between July 2017 and June 2018 were reviewed. The patients had a median prescan prostate-specific antigen value of 12.2 ng/mL (range, 1.2-81.6 ng/mL). The median injected activity of 18F-rhPSMA-7 was 327 MBq (range, 132-410 MBq), with a median uptake time of 79.5 min (range, 60-153 min). All patients underwent subsequent radical prostatectomy and extended pelvic lymph node dissection. The presence of lymph node metastases was determined by an experienced reader independently for both the PET and the morphologic datasets using a template-based analysis on a 5-point scale. Patient-level and template-based results were both compared with histopathologic findings. Results: Lymph node metastases were present in 18 patients (31.0%) and were located in 52 of 375 templates (13.9%). Receiver-operating-characteristic analyses showed 18F-rhPSMA-7 PET to perform significantly better than morphologic imaging on both patient-based and template-based analyses (areas under curve, 0.858 vs. 0.649 [P = 0.012] and 0.765 vs. 0.589 [P < 0.001], respectively). On patient-based analyses, the sensitivity, specificity, and accuracy of 18F-rhPSMA-7 PET were 72.2%, 92.5%, and 86.2%, respectively, and those of morphologic imaging were 50.0%, 72.5%, and 65.5%, respectively. On template-based analyses, the sensitivity, specificity, and accuracy of 18F-rhPSMA-7 PET were 53.8%, 96.9%, and 90.9%, respectively, and those of morphologic imaging were 9.6%, 95.0%, and 83.2%, respectively. Conclusion: 18F-rhPSMA-7 PET is superior to morphologic imaging for N-staging of high-risk primary PC. The efficacy of 18F-rhPSMA-7 is similar to published data for 68Ga-PSMA-11.
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Affiliation(s)
- Markus Kroenke
- Department of Nuclear Medicine, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | | | - Kristina Schwamborn
- Institute of Pathology, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Lena Ulbrich
- Department of Nuclear Medicine, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Lena Jooß
- Department of Nuclear Medicine, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Tobias Maurer
- Martini-Klinik and Department of Urology, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Thomas Horn
- Department of Urology, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany; and
| | - Isabel Rauscher
- Department of Nuclear Medicine, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Bernhard Haller
- Institute of Medical Informatics, Statistics and Epidemiology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Michael Herz
- Department of Nuclear Medicine, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | | | - Wolfgang A Weber
- Department of Nuclear Medicine, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Matthias Eiber
- Department of Nuclear Medicine, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
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Notni J, Wurzer A, Reichart F, Maltsev O, Steiger K, Beck R, Schwaiger M, Wester HJ, Kessler H. A 68Ga-labelled PET probe for selective imaging of αvβ8-integrin. Nucl Med Biol 2019. [DOI: 10.1016/s0969-8051(19)30240-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Maurer* T, Kroenke M, Wurzer A, Schwamborn K, Ulbrich L, Jooß L, Horn T, Haller B, Weber W, Wester HJ, Eiber M. PD17-04 DIAGNOSTIC EFFICACY OF 18F-RHPSMA7 POSITRON EMISSION TOMOGRAPHY FOR N-STAGING OF PATIENTS WITH HIGH RISK PRIMARY PROSTATE CANCER. J Urol 2019. [DOI: 10.1097/01.ju.0000555564.39848.f8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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19
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Reichart F, Maltsev OV, Kapp TG, Räder AFB, Weinmüller M, Marelli UK, Notni J, Wurzer A, Beck R, Wester HJ, Steiger K, Di Maro S, Di Leva FS, Marinelli L, Nieberler M, Reuning U, Schwaiger M, Kessler H. Selective Targeting of Integrin αvβ8 by a Highly Active Cyclic Peptide. J Med Chem 2019; 62:2024-2037. [DOI: 10.1021/acs.jmedchem.8b01588] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Florian Reichart
- Institute for Advanced Study and Center of Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Oleg V. Maltsev
- Institute for Advanced Study and Center of Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Tobias G. Kapp
- Institute for Advanced Study and Center of Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Andreas F. B. Räder
- Institute for Advanced Study and Center of Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Michael Weinmüller
- Institute for Advanced Study and Center of Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Udaya Kiran Marelli
- Central NMR Facility and Division of Organic Chemistry, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, 411008 Pune, India
| | - Johannes Notni
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meißner Straße 3, 85748 Garching, Germany
| | - Alexander Wurzer
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meißner Straße 3, 85748 Garching, Germany
| | - Roswitha Beck
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meißner Straße 3, 85748 Garching, Germany
| | - Hans-Jürgen Wester
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meißner Straße 3, 85748 Garching, Germany
| | - Katja Steiger
- Department of Pathology, Technische Universität München, Trogerstraße 18, 81675 München, Germany
| | - Salvatore Di Maro
- DiSTABiF, Università degli Studi della Campania “Luigi Vanvitelli”, Via Vivaldi 43, 81100 Caserta, Italy
| | - Francesco Saverio Di Leva
- Dipartimento di Farmacia, Università degli Studi di Napoli “Federico II”, Via D. Montesano 49, 80131 Naples, Italy
| | - Luciana Marinelli
- Dipartimento di Farmacia, Università degli Studi di Napoli “Federico II”, Via D. Montesano 49, 80131 Naples, Italy
| | - Markus Nieberler
- Department of Oral and Maxillofacial Surgery, University Hospital Rechts der Isar, Technische Universität München, Ismaninger Straße 22, 81679 München, Germany
| | | | | | - Horst Kessler
- Institute for Advanced Study and Center of Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
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Schottelius M, Wurzer A, Wissmiller K, Beck R, Koch M, Gorpas D, Notni J, Buckle T, van Oosterom MN, Steiger K, Ntziachristos V, Schwaiger M, van Leeuwen FWB, Wester HJ. Synthesis and Preclinical Characterization of the PSMA-Targeted Hybrid Tracer PSMA-I&F for Nuclear and Fluorescence Imaging of Prostate Cancer. J Nucl Med 2018; 60:71-78. [PMID: 30237214 PMCID: PMC6354225 DOI: 10.2967/jnumed.118.212720] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 07/27/2018] [Indexed: 01/13/2023] Open
Abstract
The prostate-specific membrane antigen (PSMA)–targeted radiotracers 68Ga/177Lu-PSMA-I&T and 99mTc-PSMA-I&S (for imaging and surgery) are currently successfully used for clinical PET imaging, radionuclide therapy, and radioguided surgery of metastatic prostate cancer. To additionally exploit the high sensitivity and spatial resolution of fluorescence imaging for improved surgical guidance, a PSMA-I&T–based hybrid tracer, PSMA-I&F (DOTAGA-k(Sulfo-Cy5)-y-nal-k-Sub-KuE), has been developed and evaluated. Methods: The in vitro PSMA-targeting efficiency of PSMA-I&F, the reference PSMA-I&T, and their corresponding natGa-/68Ga- and natLu/177Lu counterparts was determined in LNCaP cells via competitive binding assays (IC50) and dual-tracer radioligand and fluorescence internalization studies. Biodistribution and small-animal PET imaging studies were performed in CB17 SCID and LNCaP xenograft–bearing SHO mice, respectively, and complemented by intraoperative far-red fluorescence imaging using a clinical laparoscope. Additionally, fully automated serial cryosectioning and fluorescence imaging of 1 tumor-bearing animal as well as PSMA immunohistochemistry and fluorescence microscopy of organ cryosections (tumor, kidney, spleen) were also performed. Results: Compared with the parent PSMA-I&T analogs, the PSMA affinities of PSMA-I&F and its natGa-/natLu-complexes remained high and unaffected by dye conjugation (7.9 < IC50 < 10.5 nM for all ligands). The same was observed for the internalization of 68Ga- and 177Lu-PSMA-I&F. In vivo, blood clearance of 68Ga- and 177Lu-PSMA-I&F was only slightly delayed by high plasma protein binding (94%–95%), and very low accumulation in nontarget organs was observed already at 1 h after injection. Dynamic PET imaging confirmed PSMA-specific (as demonstrated by coinjection of 2-PMPA) uptake into the LNCaP xenograft (4.5% ± 1.8 percentage injected dose per gram) and the kidneys (106% ± 23 percentage injected dose per gram). Tumor-to-background ratios of 2.1, 5.2, 9.6, and 9.6 for blood, liver, intestines, and muscle, respectively, at 1 h after injection led to excellent imaging contrast in 68Ga-PSMA-I&F PET and in intraoperative fluorescence imaging. Furthermore, fluorescence imaging of tissue cryosections allowed high-resolution visualization of intraorgan PSMA-I&F distribution in vivo and its correlation with PSMA expression as determined by immunohistochemistry. Conclusion: Thus, with its high PSMA-targeting efficiency and favorable pharmacokinetic profile, 68Ga/177Lu-PSMA-I&F serves as an excellent proof-of-concept compound for the general feasibility of PSMA-I&T–based hybrid imaging. The PSMA-I&T scaffold represents a versatile PSMA-targeted lead structure, allowing relatively straightforward adaptation to the different structural requirements of dedicated nuclear or hybrid imaging agents.
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Affiliation(s)
- Margret Schottelius
- Chair for Pharmaceutical Radiochemistry, Technische Universität München, Garching, Germany
| | - Alexander Wurzer
- Chair for Pharmaceutical Radiochemistry, Technische Universität München, Garching, Germany
| | - Katharina Wissmiller
- Chair for Pharmaceutical Radiochemistry, Technische Universität München, Garching, Germany
| | - Roswitha Beck
- Chair for Pharmaceutical Radiochemistry, Technische Universität München, Garching, Germany
| | - Maximilian Koch
- Chair for Biological Imaging (CBI), Technische Universität München, Munich, Germany, and Institute for Biological and Medical Imaging (IBMI), Helmholtz Centre Munich, Oberschleißheim, Germany
| | - Dimitrios Gorpas
- Chair for Biological Imaging (CBI), Technische Universität München, Munich, Germany, and Institute for Biological and Medical Imaging (IBMI), Helmholtz Centre Munich, Oberschleißheim, Germany
| | - Johannes Notni
- Chair for Pharmaceutical Radiochemistry, Technische Universität München, Garching, Germany
| | - Tessa Buckle
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Matthias N van Oosterom
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Katja Steiger
- Institute for Pathology, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany; and
| | - Vasilis Ntziachristos
- Chair for Biological Imaging (CBI), Technische Universität München, Munich, Germany, and Institute for Biological and Medical Imaging (IBMI), Helmholtz Centre Munich, Oberschleißheim, Germany
| | - Markus Schwaiger
- Department of Nuclear Medicine, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany
| | - Fijs W B van Leeuwen
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Hans-Jürgen Wester
- Chair for Pharmaceutical Radiochemistry, Technische Universität München, Garching, Germany
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Abstract
Radiopharmaceuticals targeting the enzyme prostate-specific membrane antigen (PSMA; synonyms: glutamate carboxypeptidase II, NAALADase; EC 3.4.17.21) have recently emerged as powerful agents for diagnosis and therapy (theranostics) of prostate carcinoma (PCa). The radiation doses for therapeutic application of such compounds are limited by substantial uptakes in kidneys and salivary glands, with excess doses reportedly leading to radiotoxicity-related adverse effects, such as kidney insufficiency or xenostomia. On the basis of the triazacyclononane-triphosphinate (TRAP) chelator, monomeric to trimeric conjugates of the PSMA inhibitor motif lysine-urea-glutamic acid (KuE) were synthesized by means of Cu(I)-mediated (CuAAC) or 5-aza-dibenzocyclooctyne (DBCO)-driven, strain-promoted click chemistry (SPAAC), which were labeled with gallium-68 for application in positron emission tomography (PET), and characterized in terms of PSMA affinity (determined in cellular displacement assays against I-125-BA) and lipophilicity (expressed as log D). Using subcutaneous murine LNCaP (PSMA-positive human prostate carcinoma) xenografts, the influence of ligand multiplicity, affinity, polarity, and molar activity (i.e., mass dose) on the uptakes in tumor, kidney, salivary, and background (muscle) was analyzed by means of region-of-interest (ROI) based quantification of small-animal PET imaging data. As expected, trimerization of the KuE motif resulted in high PSMA affinities (IC50 ranging from 6.0-1.5 nM). Of all parameters, molar activity/cold mass had the most pronounced influence on PET uptakes. Because accumulation in nontumor tissues was effected to a larger extent than tumor uptakes, lower molar activities resulted in substantially better tumor-to-organ ratios. For example, for one trimer, 68Ga-AhxKuE3 (IC50 = 1.5 ± 0.3 nM, log D = -3.8 ± 0.1), a higher overall amount of active compound (12 pmol vs 2 nmol, equivalent to molar activities of 1200 and 8 MBq/nmol) resulted in a remarkable reduction of the kidney-to-tumor ratio from 11.4 to 1.4, respectively, at 60 min p.i. Our study suggests that, for PSMA-targeting radiopharmaceuticals, molar activity has a more pronounced influence on small-animal PET imaging results than structural or in vitro parameters.
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Affiliation(s)
- Alexander Wurzer
- Pharmaceutical Radiochemistry , Technische Universität München , Walther-Meißner-Straße 3 , D-85748 Garching , Germany
| | - Julia Pollmann
- Pharmaceutical Radiochemistry , Technische Universität München , Walther-Meißner-Straße 3 , D-85748 Garching , Germany
| | - Alexander Schmidt
- Pharmaceutical Radiochemistry , Technische Universität München , Walther-Meißner-Straße 3 , D-85748 Garching , Germany
| | - Dominik Reich
- Pharmaceutical Radiochemistry , Technische Universität München , Walther-Meißner-Straße 3 , D-85748 Garching , Germany
| | - Hans-Jürgen Wester
- Pharmaceutical Radiochemistry , Technische Universität München , Walther-Meißner-Straße 3 , D-85748 Garching , Germany
| | - Johannes Notni
- Pharmaceutical Radiochemistry , Technische Universität München , Walther-Meißner-Straße 3 , D-85748 Garching , Germany
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22
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Vágner A, Forgács A, Brücher E, Tóth I, Maiocchi A, Wurzer A, Wester HJ, Notni J, Baranyai Z. Equilibrium Thermodynamics, Formation, and Dissociation Kinetics of Trivalent Iron and Gallium Complexes of Triazacyclononane-Triphosphinate (TRAP) Chelators: Unraveling the Foundations of Highly Selective Ga-68 Labeling. Front Chem 2018; 6:170. [PMID: 29876344 PMCID: PMC5974124 DOI: 10.3389/fchem.2018.00170] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 04/27/2018] [Indexed: 11/13/2022] Open
Abstract
In order to rationalize the influence of FeIII contamination on labeling with the 68Ga eluted from 68Ge/68Ga-generator, a detailed investigation was carried out on the equilibrium properties, formation and dissociation kinetics of GaIII- and FeIII-complexes of 1,4,7-triazacyclononane-1,4,7-tris(methylene[2-carboxyethylphosphinic acid]) (H6TRAP). The stability and protonation constants of the [Fe(TRAP)]3- complex were determined by pH-potentiometry and spectrophotometry by following the competition reaction between the TRAP ligand and benzhydroxamic acid (0.15 M NaNO3, 25°C). The formation rates of [Fe(TRAP)] and [Ga(TRAP)] complexes were determined by spectrophotometry and 31P-NMR spectroscopy in the pH range 4.5-6.5 in the presence of 5-40 fold HxTRAP(x-6) excess (x = 1 and 2, 0.15 M NaNO3, 25°C). The kinetic inertness of [Fe(TRAP)]3- and [Ga(TRAP)]3- was examined by the trans-chelation reactions with 10 to 20-fold excess of HxHBED(x-4) ligand by spectrophotometry at 25°C in 0.15 M NaCl (x = 0,1 and 2). The stability constant of [Fe(TRAP)]3- (logKFeL = 26.7) is very similar to that of [Ga(TRAP)]3- (logKGaL = 26.2). The rates of ligand exchange reaction of [Fe(TRAP)]3- and [Ga(TRAP)]3- with HxHBED(x-4) are similar. The reactions take place quite slowly via spontaneous dissociation of [M(TRAP)]3-, [M(TRAP)OH]4- and [M(TRAP)(OH)2]5- species. Dissociation half-lives (t1/2) of [Fe(TRAP)]3- and [Ga(TRAP)]3- complexes are 1.1 × 105 and 1.4 × 105 h at pH = 7.4 and 25°C. The formation reactions of [Fe(TRAP)]3- and [Ga(TRAP)]3- are also slow due to the formation of the unusually stable monoprotonated [*M(HTRAP)]2- intermediates [*logKGa(HL) = 10.4 and *logKFe(HL) = 9.9], which are much more stable than the [*Ga(HNOTA)]+ intermediate [*logKGa(HL) = 4.2]. Deprotonation and transformation of the monoprotonated [*M(HTRAP)]2- intermediates into the final complex occur via OH--assisted reactions. Rate constants (kOH) characterizing the OH--driven deprotonation and transformation of [* Ga(HTRAP)]2- and [*Fe(HTRAP)]2- intermediates are 1.4 × 105 M-1s-1 and 3.4 × 104 M-1s-1, respectively. In conclusion, the equilibrium and kinetic properties of [Fe(TRAP)] and [Ga(TRAP)] complexes are remarkably similar due to the close physico-chemical properties of FeIII and GaIII-ions. However, a slightly faster formation of [Ga(TRAP)] over [Fe(TRAP)] provides a rationale for a previously observed, selective complexation of 68GaIII in presence of excess FeIII.
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Affiliation(s)
- Adrienn Vágner
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Attila Forgács
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Ernő Brücher
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Imre Tóth
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | | | - Alexander Wurzer
- Radiopharmaceutical Chemistry, Technische Universität München, Garching bei München, Germany
| | - Hans-Jürgen Wester
- Radiopharmaceutical Chemistry, Technische Universität München, Garching bei München, Germany
| | - Johannes Notni
- Radiopharmaceutical Chemistry, Technische Universität München, Garching bei München, Germany
| | - Zsolt Baranyai
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary.,Bracco Imaging S.p.a., Bracco Research Centre, Colleretto Giacosa, Italy
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Wurzer A, Vágner A, Horváth D, Fellegi F, Wester HJ, Kálmán FK, Notni J. Synthesis of Symmetrical Tetrameric Conjugates of the Radiolanthanide Chelator DOTPI for Application in Endoradiotherapy by Means of Click Chemistry. Front Chem 2018; 6:107. [PMID: 29692987 PMCID: PMC5902495 DOI: 10.3389/fchem.2018.00107] [Citation(s) in RCA: 4] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 03/22/2018] [Indexed: 12/27/2022] Open
Abstract
Due to its 4 carbonic acid groups being available for bioconjugation, the cyclen tetraphosphinate chelator DOTPI, 1,4,7,10-tetraazacyclododecane-1,4,7, 10-tetrakis[methylene(2-carboxyethylphosphinic acid)], represents an ideal scaffold for synthesis of tetrameric bioconjugates for labeling with radiolanthanides, to be applied as endoradiotherapeuticals. We optimized a protocol for bio-orthogonal DOTPI conjugation via Cu(I)-catalyzed Huisgen-cycloaddition of terminal azides and alkynes (CuAAC), based on the building block DOTPI(azide)4. A detailed investigation of kinetic properties of Cu(II)-DOTPI complexes aimed at optimization of removal of DOTPI-bound copper by transchelation. Protonation and equilibrium properties of Ca(II)-, Zn(II), and Cu(II)-complexes of DOTPI and its tetra-cyclohexylamide DOTPI(Chx)4 (a model for DOTPI conjugates) as well as kinetic inertness (transchelation challenge in the presence of 20 to 40-fold excess of EDTA) were investigated by pH-potentiometry and spectrophotometry. Similar stability constants of CaII-, ZnII, and CuII-complexes of DOTPI (logK(CaL) = 8.65, logK(ZnL = 15.40, logK(CuL) = 20.30) and DOTPI(Chx)4 (logK(CaL) = 8.99, logK(ZnL) = 15.13, logK(CuL) = 20.42) were found. Transchelation of Cu(II)-complexes occurs via proton-assisted dissociation, whereafter released Cu(II) is scavenged by EDTA. The corresponding dissociation rates [kd = 25 × 10−7 and 5 × 10−7 s−1 for Cu(DOTPI) and Cu(DOTPI(Chx)4), respectively, at pH 4 and 298 K] indicate that conjugation increases the kinetic inertness by a factor of 5. However, demetallation is completed within 4.5 and 7.2 h at pH 2 and 25°C, respectively, indicating that Cu(II) removal after formation of CuAAC can be achieved in an uncomplicated manner by addition of excess H4EDTA. For proof-of-principle, tetrameric DOTPI conjugates of the prostate-specific membrane antigen (PSMA) targeting motif Lys-urea-Glu (KuE) were synthesized via CuAAC as well as dibenzo-azacyclooctine (DBCO) based, strain-promoted click chemistry (SPAAC), which were labeled with Lu-177 and subsequently evaluated in vitro and in SCID mice bearing subcutaneous LNCaP tumor (PSMA+ human prostate carcinoma) xenografts. High affinities (3.4 and 1.4 nM, respectively) and persistent tumor uptakes (approx. 3.5% 24 h after injection) confirm suitability of DOTPI-based tetramers for application in targeted radionuclide therapy.
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Affiliation(s)
- Alexander Wurzer
- Pharmaceutical Radiochemistry, Technische Universität München, Munich, Germany
| | - Adrienn Vágner
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Dávid Horváth
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Flóra Fellegi
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Hans-Jürgen Wester
- Pharmaceutical Radiochemistry, Technische Universität München, Munich, Germany
| | - Ferenc K Kálmán
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Johannes Notni
- Pharmaceutical Radiochemistry, Technische Universität München, Munich, Germany
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Reich D, Wurzer A, Wirtz M, Stiegler V, Spatz P, Pollmann J, Wester HJ, Notni J. Dendritic poly-chelator frameworks for multimeric bioconjugation. Chem Commun (Camb) 2018; 53:2586-2589. [PMID: 28191563 DOI: 10.1039/c6cc10169k] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Starting from multifunctional triazacyclononane-triphosphinate chelator cores, dendritic molecules with the ability to bind metal ions within their framework were synthesized. A cooperative interaction of the chelator cages resulted in a markedly increased affinity towards 67/68GaIII. A hexameric PSMA inhibitor conjugate with high affinity (IC50 = 1.2 nM) and favorable in vivo PET imaging properties demonstrated practical applicability. The novel scaffolds are useful for synthesis of structurally well-defined multimodal imaging probes or theranostics.
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Affiliation(s)
- Dominik Reich
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meissner-Strasse 3, D-85748 Garching, Germany.
| | - Alexander Wurzer
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meissner-Strasse 3, D-85748 Garching, Germany.
| | - Martina Wirtz
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meissner-Strasse 3, D-85748 Garching, Germany.
| | - Veronika Stiegler
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meissner-Strasse 3, D-85748 Garching, Germany.
| | - Philipp Spatz
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meissner-Strasse 3, D-85748 Garching, Germany.
| | - Julia Pollmann
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meissner-Strasse 3, D-85748 Garching, Germany.
| | - Hans-Jürgen Wester
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meissner-Strasse 3, D-85748 Garching, Germany.
| | - Johannes Notni
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meissner-Strasse 3, D-85748 Garching, Germany.
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Färber S, Wurzer A, Reichart F, Beck R, Kessler H, Wester HJ, Notni J. Therapeutic Radiopharmaceuticals Targeting Integrin αvβ6. ACS Omega 2018; 3:2428-2436. [PMID: 30023833 PMCID: PMC6045477 DOI: 10.1021/acsomega.8b00035] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 02/19/2018] [Indexed: 05/08/2023]
Abstract
The epithelial integrin αvβ6 is expressed by many malignant carcinoma cell types, including pancreatic cancer, and thus represents a promising target for radionuclide therapy. The peptide cyclo(FRGDLAFp(NMe)K) was decorated with different chelators (DOTPI, DOTAGA, and DOTA). The Lu(III) complexes of these conjugates exhibited comparable αvβ6 integrin affinities (IC50 ranging from 0.3 to 0.8 nM) and good selectivities against other integrins (IC50 for αvβ8 >43 nM; for α5β1 >238 nM; and for αvβ3, αvβ5, and αIIbβ3 >1000 nM). Although different formal charges of the Lu(III) chelates (ranging from 0 to 4) resulted in strongly varying degrees of hydrophilicity (log D ranging from -3.0 to -4.1), biodistributions in murine H2009 xenografts of the Lu-177-labeled compounds (except the DOTPI derivative) were quite similar and comparable to our previously reported αvβ6 integrin positron emission tomography tracer Ga-68-avebehexin. Hence, combinations of existing Ga-68- and Lu-177-labeled c(FRGDLAFp(NMe)K) derivatives could be utilized for αvβ6 integrin-targeted theranostics, whereas our data nonetheless suggest that further improvement of pharmacokinetics might be necessary to ensure clinical success.
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Affiliation(s)
- Stefanie
Felicitas Färber
- Lehrstuhl für
Pharmazeutische Radiochemie and Institute for Advanced Study and
Center of Integrated Protein Science (CIPSM), Department of Chemistry, Technische Universität München, Garching D-85748, Germany
| | - Alexander Wurzer
- Lehrstuhl für
Pharmazeutische Radiochemie and Institute for Advanced Study and
Center of Integrated Protein Science (CIPSM), Department of Chemistry, Technische Universität München, Garching D-85748, Germany
| | - Florian Reichart
- Lehrstuhl für
Pharmazeutische Radiochemie and Institute for Advanced Study and
Center of Integrated Protein Science (CIPSM), Department of Chemistry, Technische Universität München, Garching D-85748, Germany
| | - Roswitha Beck
- Lehrstuhl für
Pharmazeutische Radiochemie and Institute for Advanced Study and
Center of Integrated Protein Science (CIPSM), Department of Chemistry, Technische Universität München, Garching D-85748, Germany
| | - Horst Kessler
- Lehrstuhl für
Pharmazeutische Radiochemie and Institute for Advanced Study and
Center of Integrated Protein Science (CIPSM), Department of Chemistry, Technische Universität München, Garching D-85748, Germany
| | - Hans-Jürgen Wester
- Lehrstuhl für
Pharmazeutische Radiochemie and Institute for Advanced Study and
Center of Integrated Protein Science (CIPSM), Department of Chemistry, Technische Universität München, Garching D-85748, Germany
| | - Johannes Notni
- Lehrstuhl für
Pharmazeutische Radiochemie and Institute for Advanced Study and
Center of Integrated Protein Science (CIPSM), Department of Chemistry, Technische Universität München, Garching D-85748, Germany
- E-mail: , http://www.prc.ch.tum.de (J.N.)
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Kapp TG, Di Leva FS, Notni J, Räder AFB, Fottner M, Reichart F, Reich D, Wurzer A, Steiger K, Novellino E, Marelli UK, Wester HJ, Marinelli L, Kessler H. N-Methylation of isoDGR Peptides: Discovery of a Selective α5β1-Integrin Ligand as a Potent Tumor Imaging Agent. J Med Chem 2018; 61:2490-2499. [DOI: 10.1021/acs.jmedchem.7b01752] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Tobias G. Kapp
- Institute for Advanced Study and Center of Integrated Protein Science, Department Chemie, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Francesco Saverio Di Leva
- Dipartimento di Farmacia, Università degli Studi di Napoli “Federico II”, Via D. Montesano 49, 80131 Naples, Italy
| | - Johannes Notni
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meißner Straße 3, 85748 Garching, Germany
| | - Andreas F. B. Räder
- Institute for Advanced Study and Center of Integrated Protein Science, Department Chemie, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Maximilian Fottner
- Institute for Advanced Study and Center of Integrated Protein Science, Department Chemie, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Florian Reichart
- Institute for Advanced Study and Center of Integrated Protein Science, Department Chemie, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Dominik Reich
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meißner Straße 3, 85748 Garching, Germany
| | - Alexander Wurzer
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meißner Straße 3, 85748 Garching, Germany
| | - Katja Steiger
- Department of Pathology, Technische Universität München, Trogerstraße 18, 81675 München, Germany
| | - Ettore Novellino
- Dipartimento di Farmacia, Università degli Studi di Napoli “Federico II”, Via D. Montesano 49, 80131 Naples, Italy
| | - Udaya Kiran Marelli
- Central NMR Facility and Division of Organic Chemistry, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, 411008 Pune, India
| | - Hans-Jürgen Wester
- Lehrstuhl für Pharmazeutische Radiochemie, Technische Universität München, Walther-Meißner Straße 3, 85748 Garching, Germany
| | - Luciana Marinelli
- Dipartimento di Farmacia, Università degli Studi di Napoli “Federico II”, Via D. Montesano 49, 80131 Naples, Italy
| | - Horst Kessler
- Institute for Advanced Study and Center of Integrated Protein Science, Department Chemie, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
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Wurzer A, Seidl C, Morgenstern A, Bruchertseifer F, Schwaiger M, Wester HJ, Notni J. Cover Feature: Dual-Nuclide Radiopharmaceuticals for Positron Emission Tomography Based Dosimetry in Radiotherapy (Chem. Eur. J. 3/2018). Chemistry 2018. [DOI: 10.1002/chem.201704983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Alexander Wurzer
- Pharmaceutical Radiochemistry; Technische Universität München; Walther-Meißner-Strasse 3 85748 Garching Germany
| | - Christof Seidl
- Department of Nuclear Medicine; Technische Universität München; Germany
- Department of Obstetrics and Gynecology; Technische Universität München; Germany
| | - Alfred Morgenstern
- European Commission, Joint Research Centre; Directorate for Nuclear Safety and Security; Karlsruhe Germany
| | - Frank Bruchertseifer
- European Commission, Joint Research Centre; Directorate for Nuclear Safety and Security; Karlsruhe Germany
| | - Markus Schwaiger
- Department of Nuclear Medicine; Technische Universität München; Germany
| | - Hans-Jürgen Wester
- Pharmaceutical Radiochemistry; Technische Universität München; Walther-Meißner-Strasse 3 85748 Garching Germany
| | - Johannes Notni
- Pharmaceutical Radiochemistry; Technische Universität München; Walther-Meißner-Strasse 3 85748 Garching Germany
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Wurzer A, Seidl C, Morgenstern A, Bruchertseifer F, Schwaiger M, Wester H, Notni J. Dual-Nuclide Radiopharmaceuticals for Positron Emission Tomography Based Dosimetry in Radiotherapy. Chemistry 2018; 24:547-550. [PMID: 28833667 PMCID: PMC5813229 DOI: 10.1002/chem.201702335] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Indexed: 01/15/2023]
Abstract
Improvement of the accuracy of dosimetry in radionuclide therapy has the potential to increase patient safety and therapeutic outcomes. Although positron emission tomography (PET) is ideally suited for acquisition of dosimetric data because PET is inherently quantitative and offers high sensitivity and spatial resolution, it is not directly applicable for this purpose because common therapeutic radionuclides lack the necessary positron emission. This work reports on the synthesis of dual-nuclide labeled radiopharmaceuticals with therapeutic and PET functionality, which are based on common and widely available metal radionuclides. Dual-chelator conjugates, featuring interlinked cyclen- and triazacyclononane-based polyphosphinates DOTPI and TRAP, allow for strictly regioselective complexation of therapeutic (e.g., 177 Lu, 90 Y, or 213 Bi) and PET (e.g., 68 Ga) radiometals in the same molecular framework by exploiting the orthogonal metal ion selectivity of these chelators (DOTPI: large cations, such as lanthanide(III) ions; TRAP: small trivalent ions, such as GaIII ). Such DOTPI-TRAP conjugates were decorated with 3 Gly-urea-Lys (KuE) motifs for targeting prostate-specific membrane antigen (PSMA), employing Cu-catalyzed (CuAAC) as well as strain-promoted (SPAAC) click chemistry. These were labeled with 177 Lu or 213 Bi and 68 Ga and used for in vivo imaging of LNCaP (human prostate carcinoma) tumor xenografts in SCID mice by PET, thus proving practical applicability of the concept.
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Affiliation(s)
- Alexander Wurzer
- Pharmaceutical RadiochemistryTechnische Universität MünchenWalther-Meißner-Strasse 385748GarchingGermany
| | - Christof Seidl
- Department of Nuclear MedicineTechnische Universität MünchenGermany
- Department of Obstetrics and GynecologyTechnische Universität MünchenGermany
| | - Alfred Morgenstern
- European Commission, Joint Research CentreDirectorate for Nuclear Safety and SecurityKarlsruheGermany
| | - Frank Bruchertseifer
- European Commission, Joint Research CentreDirectorate for Nuclear Safety and SecurityKarlsruheGermany
| | - Markus Schwaiger
- Department of Nuclear MedicineTechnische Universität MünchenGermany
| | - Hans‐Jürgen Wester
- Pharmaceutical RadiochemistryTechnische Universität MünchenWalther-Meißner-Strasse 385748GarchingGermany
| | - Johannes Notni
- Pharmaceutical RadiochemistryTechnische Universität MünchenWalther-Meißner-Strasse 385748GarchingGermany
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