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Clinical Trial
. 2025 Apr 1;66(4):626-633.
doi: 10.2967/jnumed.124.268872.

Biodistribution, Safety Profile, and Radiation Dosimetry of [18F]SYN2, a PET Cardiac Perfusion Tracer, in Healthy Subjects

Juhani Knuuti  1   2 , Małgorzata Kobylecka  3 , Seweryn Krajewski  4 , Lukasz Steczek  5 , Karina Gotowicz  5   6 , Joanna Towpik  5 , Kari Kalliokoski  1 , Tuula Tolvanen  1 , Magdalena Kostkiewicz  7   8 , Przemysław Kozanecki  5 , Joanna Włostowska  5 , Mirosław Dziuk  9   10 , Leszek Królicki  3 , Jacek Bil  11 , Piotr J Slomka  12 , Timothy M Bateman  13 , Mouaz H Al-Mallah  14 , Panithaya Chareonthaitawee  15 , Prem Soman  16 , Cezary Kozanecki  5
Affiliations
Clinical Trial

Biodistribution, Safety Profile, and Radiation Dosimetry of [18F]SYN2, a PET Cardiac Perfusion Tracer, in Healthy Subjects

Juhani Knuuti et al. J Nucl Med. .

Abstract

A first-in-human phase I clinical study aimed to assess the safety profile, radiation dosimetry, and biodistribution of a potential cardiac PET myocardial perfusion imaging tracer, [18F]SYN2 (18F-labeled acridine derivative), in healthy subjects. Methods: [18F]SYN2 intravenous administration with PET imaging was performed on healthy volunteers, and sequential whole-body imaging was performed over 4 h. Blood and urine samples were collected for up to 240 min. Safety follow-up visits took place at 2, 5, and 14 d after the administration. Results: Ten subjects (8 women and 2 men) completed all study procedures. The mean age was 38.1 ± 8.8 y, and the mean body mass index was 22.7 ± 3.0 kg/m2 The mean administered dose of radioactivity was 258 MBq (range, 246-272 MBq). There were no drug-related adverse events, and the tracer was well tolerated in all subjects. The mean whole-body effective radiation dose for [18F]SYN2 was 0.0195 mSv/MBq. The tracer was rapidly taken up by the myocardial wall and cleared from plasma, leading to good image quality within minutes of tracer injection. Conclusion: On the basis of the safety profile, radiation dosimetry, and biodistribution of [18F]SYN2, it appears to be a promising agent for clinical PET myocardial perfusion imaging and to warrant further clinical studies.

Keywords: MPI; PET imaging; [18F]SYN2; [18F]tracer; cardiac imaging; phase I clinical study.

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Figures

None
Graphical abstract
FIGURE 1.
FIGURE 1.
Acquisition timeline of PET and CT scans in phase I study. (A) PET scanning protocol for first 3 subjects. (B) PET scanning protocol for last 7 subjects.
FIGURE 2.
FIGURE 2.
Sequence of acquired whole-body relative maximum-intensity projection images in subject S011.
FIGURE 3.
FIGURE 3.
Time–activity curves. (A) Individual whole blood time–activity curves for all 10 subjects. (B) Individual plasma time–activity curves for all 10 subjects. (C) Individual red blood cell time–activity curves for all 10 subjects. Subjects S002 and S003 were male, and all others were female.
FIGURE 4.
FIGURE 4.
Uptake of [18F]SYN2 into thoracic region at different time points up to 210 min after injection. Left ventricular wall was rapidly and clearly visualized early after injection. Tracer uptake remained stable in myocardium until end of scan.
FIGURE 5.
FIGURE 5.
Example of dynamic cardiac images at each period during 15-min dynamic cardiac scan (subject S003). Myocardium was already well visualized 3 min after injection of [18F]SYN2. There was high tracer uptake in stomach, but that was not very close to heart.
FIGURE 6.
FIGURE 6.
Time–activity curves of myocardium (yellow line) and blood (white line) in 2 cases (S0014 [A] and S0018 [B]). [18F]SYN2 was rapidly taken up by left ventricle wall, and tracer concentration remained stable until end of 5-min dynamic scan. Activity was rapidly cleared from circulation as compared with myocardium.
See this image and copyright information in PMC

References

    1. Knuuti J, Wijns W, Saraste A, et al.; ESC Scientific Document Group. 2019 ESC guidelines for the diagnosis and management of chronic coronary syndromes. Eur Heart J. 2020;41:407–477. - PubMed
    1. Marcassa C, Bax JJ, Bengel F, et al.; European Association of Nuclear Medicine Cardiovascular Committee. Clinical value, cost-effectiveness, and safety of myocardial perfusion scintigraphy: a position statement. Eur Heart J. 2008;29:557–563. - PubMed
    1. Kostkiewicz M. Myocardial perfusion imaging in coronary artery disease. Cor et Vasa. 2015;57:e446–e452.
    1. Nekolla SG, Saraste A. Novel F-18-labeled PET myocardial perfusion tracers: bench to bedside. Curr Cardiol Rep. 2011;13:145–150. - PubMed
    1. Rischpler C, Park MJ, Fung GS, Javadi M, Tsui BM, Higuchi T. Advances in PET myocardial perfusion imaging: F-18 labeled tracers. Ann Nucl Med. 2012;26:1–6. - PubMed

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