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Preclinical In Vitro and In Vivo Characterization of Synaptic Vesicle 2A–Targeting Compounds Amenable to F-18 Labeling as Potential PET Radioligands for Imaging of Synapse Integrity

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Abstract

Purpose

Current synaptic vesicle 2A (SV2A) positron emission tomography (PET) imaging agents include the nanomolar affinity probes [11C]UCB-J and [18F]UCB-H derived from the anti-epileptic drug levitaracetam (Keppra®). An industry-utilized “de-risking” approach was used to carry out initial pharmacological characterization and to assess potential next-generation candidates amenable to F-18 radiolabeling for preliminary evaluation.

Procedures

Radioligand binding methods were employed in mammalian brain homogenates to determine the SV2A affinity (Kd) and maximal binding capacity (Bmax) of [3H]UCB-J. Novel leads were then screened to identify compounds minimally with comparable binding affinities with UCB-J in order to select a F-18-labeled candidate for subsequent in vivo assessment in rat. In parallel, mammalian brain tissue section autoradiography was performed to assess specific SV2A distribution.

Results

[3H]UCB-J bound with high affinity to a single population of sites in the rat brain (Kd = 2.6 ± 0.25 nM; Bmax = 810 ± 25 fmol/mg protein) and control human cortex (Kd = 2.9 ± 0.54 nM; Bmax = 10,000 ± 640 fmol/mg protein). Distribution of specific SV2A binding was shown to be homogeneous throughout the rodent brain and primarily in gray matter regions of rodent and human brain sections. Analog screening identified MNI-1038, MNI-1126/SDM-8, and SDM-2 as having comparable binding affinities with the currently available PET ligands. Subsequent [18F]MNI-1126/[18F]SDM-8 dynamic micro-PET imaging in rats revealed in vivo uptake and accumulation in the brain with favorable kinetics. Chase studies using 30 mg/kg levetiracetam confirmed that in vivo brain uptake of [18F]MNI-1126/[18F]SDM-8 was reversible.

Conclusions

Taken together, these data suggest [18F]MNI-1126/[18F]SDM-8 (since renamed as [18F]SynVesT-1) characterized via an in vitro screening cascade provided a measurable in vivo SV2A specific signal in the rodent brain. This tracer as well as the close analog [18F]SDM-2 (since renamed as [18F]SynVesT-2) is currently undergoing further evaluation in preclinical and clinical studies.

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References

  1. Bajjalieh SM, Frantz GD, Weimann JM, McConnell S, Scheller RH (1994) Differential expression of synaptic vesicle protein 2 (SV2) isoforms. J Neurosci 14:5223–5235

    Article  CAS  Google Scholar 

  2. Crowder KM, Gunther JM, Jones TA, Hale BD, Zhang HZ, Peterson MR, Scheller RH, Chavkin C, Bajjalieh SM (1999) Abnormal neurotransmission in mice lacking synaptic vesicle protein 2A (SV2A). Proc Natl Acad Sci 96:15268–15273

    Article  CAS  Google Scholar 

  3. Jahn R, Fasshauer D (2012) Molecular machines governing exocytosis of synaptic vesicles. Nature 490:201–207

    Article  CAS  Google Scholar 

  4. Mendoza-Torreblanca JG, Vanoye-Carlo A, Phillips-Farfán BV et al (2013) Synaptic vesicle protein 2A: basic facts and role in synaptic function. Eur J Neurosci 38:3529–3539

    Article  Google Scholar 

  5. Vogl C, Tanifuji S, Danis B, Daniels V, Foerch P, Wolff C, Whalley BJ, Mochida S, Stephens GJ (2015) Synaptic vesicle glycoprotein 2A modulates vesicular release and calcium channel function at peripheral sympathetic synapses. Eur J Neurosci 41:398–409

    Article  Google Scholar 

  6. Lynch BA, Lambeng N, Nocka K, Kensel-Hammes P, Bajjalieh SM, Matagne A, Fuks B (2004) The synaptic vesicle protein SV2A is the binding site for the antiepileptic drug levetiracetam. Proc Natl Acad Sci U S A 101:9861–9866

    Article  CAS  Google Scholar 

  7. Kenda BM, Matagne AC, Talaga PE, Pasau PM, Differding E, Lallemand BI, Frycia AM, Moureau FG, Klitgaard HV, Gillard MR, Fuks B, Michel P (2004) Discovery of 4-substituted pyrrolidone butanamides as new agents with significant antiepileptic activity. J Med Chem 47:530–549

    Article  CAS  Google Scholar 

  8. von Rosenstiel P (2007) Brivaracetam (UCB 34714). Neurotherapeutics 4(1):84–87

  9. Ohno Y, Tokudome K (2017) Therapeutic role of synaptic vesicle glycoprotein 2A (SV2A) in modulating epileptogenisis. CNS Neurol Disord Drug Targets 16:463–471

    CAS  PubMed  Google Scholar 

  10. Löscher W, Gillard M, Sands ZA, Kaminski RM, Klitgaard H (2016) Synaptic vesicle glycoprotein 2A ligands in the treatment of epilepsy and beyond. CNS Drugs 30:1055–1077

    Article  Google Scholar 

  11. Lever SZ, Fan KH, Lever JR (2017) Tactics for preclinical validation of receptor-binding radiotracers. Nucl Med Biol 44:4–30

    Article  CAS  Google Scholar 

  12. Hargreaves RJ, Hoppin J, Sevigny J, Patel S, Chiao P, Klimas M, Verma A (2015) Optimizing central nervous system drug development using molecular imaging. Clin Pharmacol Ther 98:47–60

    Article  CAS  Google Scholar 

  13. Patel S, Hamill TG, Connolly B, Jagoda E, Li W, Gibson RE (2007) Species differences in mGluR5 binding sites in mammalian central nervous system determined using in vitro binding with [18F]F-PEB. Nucl Med Biol 34:1009–1017

    Article  CAS  Google Scholar 

  14. Patel S, Ndubizu O, Hamill T, Chaudhary A, Burns HD, Hargreaves R, Gibson RE (2005) Screening cascade and development of potential positron emission tomography radiotracers for mGluR5: in vitro and in vivo characterization. Mol Imaging Biol 7:314–323

    Article  Google Scholar 

  15. Patel S, Hammil T, Hostetler E et al (2003) An invitro assay for predicting successful imaging radiotracers. Mol Imaging Biol 5:65–71

    Article  Google Scholar 

  16. Patel S, Gibson R (2008) In vivo site-directed radiotracers: a mini-review. Nucl Med Biol 35:805–815

    Article  CAS  Google Scholar 

  17. Gillard M, Fuks B, Leclercq K, Matagne A (2011) Binding characteristics of brivaracetam, a selective, high affinity SV2A ligand in rat, mouse and human brain: relationship to anti-convulsant properties. Eur J Pharmacol 664:36–44

    Article  CAS  Google Scholar 

  18. Warnier C, Lemaire C, Becker G, Zaragoza G, Giacomelli F, Aerts J, Otabashi M, Bahri MA, Mercier J, Plenevaux A, Luxen A (2016) Enabling efficient positron emission tomography (PET) imaging of synaptic vesicle glycoprotein 2A (SV2A) with a robust and one-step adiosynthesis of a highly potent 18F-labeled ligand ([18F]UCB-H). J Med Chem 59:8955–8966

    Article  CAS  Google Scholar 

  19. Nabulsi NB, Mercier J, Holden D, Carre S, Najafzadeh S, Vandergeten MC, Lin SF, Deo A, Price N, Wood M, Lara-Jaime T, Montel F, Laruelle M, Carson RE, Hannestad J, Huang Y (2016) Synthesis and preclinical evaluation of 11C-UCB-J as a PET tracer for imaging the synaptic vesicle glycoprotein 2A in the brain. J Nucl Med 57:777–784

    Article  CAS  Google Scholar 

  20. Finnema SJ, Nabulsi NB, Eid T, Detyniecki K, Lin SF, Chen MK, Dhaher R, Matuskey D, Baum E, Holden D, Spencer DD, Mercier J, Hannestad J, Huang Y, Carson RE (2016) Imaging synaptic density in the living human brain. Sci Transl Med 8:348ra96

    Article  Google Scholar 

  21. Finnema SJ, Nabulsi NB, Mercier J, Lin SF, Chen MK, Matuskey D, Gallezot JD, Henry S, Hannestad J, Huang Y, Carson RE (2018) Kinetic evaluation and test-retest reproducibility of [11C]UCB-J, a novel radioligand for positron emission tomography imaging of synaptic vesicle glycoprotein 2A in humans. J Cereb Blood Flow Metab 38:2041–2052

    Article  CAS  Google Scholar 

  22. Li S, Cai Z, Wu X, Holden D, Pracitto R, Kapinos M, Gao H, Labaree D, Nabulsi N, Carson RE, Huang Y (2019) Synthesis and in vivo evaluation of a novel PET radiotracer for imaging of synaptic vesicle glycoprotein 2A (SV2A) in nonhuman primates. ACS Chem Neurosci 10:1544–1554

    Article  CAS  Google Scholar 

  23. Cheng Y, Prusoff WH (1973) Relationship between the inhibition constant (Ki) and the concentration of inhibitor which causes 50 per cent inhibition (I50) of an enzymatic reaction. Biochem Pharmacol 22:3099–3108

    Article  CAS  Google Scholar 

  24. Patel S, Hamill T, Hostetler E et al (2003) An in-vitro assay for predicting successful imaging radiotracers. Mol Imaging Biol 5:65–71

    Article  Google Scholar 

  25. Nicolas JM, Hannestad J, Holden D, Kervyn S, Nabulsi N, Tytgat D, Huang Y, Chanteux H, Staelens L, Matagne A, Mathy FX, Mercier J, Stockis A, Carson RE, Klitgaard H (2016) Brivaracetam, a selective high-affinity synaptic vesicle protein 2A (SV2A) ligand with preclinical evidence of high brain permeability and fast onset of action. Epilepsia 57:201–209

    Article  CAS  Google Scholar 

  26. Eckelman WC, Gibson RE (1993) The design of site-directed radiopharmaceuticals for use in drug discovery. In: Burns HD, Gibson RE, Dannals R, Siegl P (eds) Nuclear imaging and drug discovery, development and approval. Birkhauser, Boston, pp 114–134

    Google Scholar 

  27. Chen MK, Mecca AP, Naganawa M, Finnema SJ, Toyonaga T, Lin SF, Najafzadeh S, Ropchan J, Lu Y, McDonald JW, Michalak HR, Nabulsi NB, Arnsten AFT, Huang Y, Carson RE, van Dyck CH (2018) Assessing synaptic density in Alzheimer disease with synaptic vesicle glycoprotein 2A positron emission tomographic imaging. JAMA Neurol 75:1215–1224

    Article  Google Scholar 

  28. Dawson TM, Golde TE, Lagier-Tourenne C (2018) Animal models of neurodegenerative diseases. Nat Neurosci 21:1370–1379

    Article  CAS  Google Scholar 

  29. Sasaguri H, Nilsson P, Hashimoto S, Nagata K, Saito T, de Strooper B, Hardy J, Vassar R, Winblad B, Saido TC (2017) APP mouse models for Alzheimer’s disease preclinical studies. EMBO J 36:2473–2487

    Article  CAS  Google Scholar 

  30. Constantinescu CC, Tresse C, Zheng M, Gouasmat A, Carroll VM, Mistico L, Alagille D, Sandiego CM, Papin C, Marek K, Seibyl JP, Tamagnan GD, Barret O (2019) Development and in vivo preclinical imaging of fluorine-18-labeled synaptic vesicle protein 2A (SV2A) PET tracers. Mol Imaging Biol 21:509–518

    Article  CAS  Google Scholar 

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Authors and Affiliations

  1. Codiak Biosciences, 500 Technology Square, 9th Floor, Cambridge, MA, 02139, USA

    Shil Patel

  2. Centre for Addiction and Mental Health, University of Toronto, 250 College Street, Toronto, ON, M5T 1R8, Canada

    Ashley Knight

  3. Eisai Inc., 100 Tice Blvd, Woodcliff Lake, NJ, 07677, USA

    Stephen Krause & Tyler Teceno

  4. Invicro, LLC, 27 Drydock Ave. 7th Floor West, Boston, MA, 02210, USA

    Cedric Tresse, Alexandra Gouasmat, Vincent M. Carroll, Olivier Barret, Vijay Gottmukkala, Thomas Morley & Jan Passchier

  5. PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, 801 Howard Avenue, New Haven, CT, 06510, USA

    Songye Li, Zhengxin Cai & Yiyun Huang

  6. Department of Nuclear Medicine, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China

    Wenjie Zhang

  7. Department of Interventional Radiology, The First Affiliated Hospital of Sun Yat-Sen University, 58 Zhongshan Second Road, Yuexiu District, Guangzhou, 510080, China

    Xianhong Xiang

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  1. Shil Patel
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Correspondence to Shil Patel.

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Patel, S., Knight, A., Krause, S. et al. Preclinical In Vitro and In Vivo Characterization of Synaptic Vesicle 2A–Targeting Compounds Amenable to F-18 Labeling as Potential PET Radioligands for Imaging of Synapse Integrity. Mol Imaging Biol 22, 832–841 (2020). https://doi.org/10.1007/s11307-019-01428-0

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