Human biodistribution and dosimetry of [11C]-UCB-J, a PET radiotracer for imaging synaptic density

• Published in: EJNMMI physics Vol. 8; no. 1; pp. 37 - 11
• Main Authors: Cawthorne, Christopher, Maguire, Paul, Mercier, Joel, Sciberras, David, Serdons, Kim, Bormans, Guy, de Hoon, Jan, Van Laere, Koen, Koole, Michel
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 23.04.2021; Springer Nature B.V; SpringerOpen
• Subjects: [11C]-UCB-J; Activity coefficients; Applied and Technical Physics; Biodistribution; Bladder; Computational Mathematics and Numerical Analysis; Density; Dosimeters; Dosimetry; Engineering; Human biodistribution; Imaging; Intestine; Mathematical analysis; Medicine; Medicine & Public Health; Nuclear Medicine; OLINDA; Organs; Positron emission; Radiation dosimetry; Radioactive tracers; Radiology; Short Communication; Synaptic density; Tomography; Radiation dosimetry; [; Synaptic density; Human biodistribution; C]-UCB-J; OLINDA; [11C]-UCB-J
• ISSN: 2197-7364; 2197-7364
• DOI: 10.1186/s40658-021-00384-5

Rationale [ 11 C]-UCB-J is an emerging tool for the noninvasive measurement of synaptic vesicle density in vivo. Here, we report human biodistribution and dosimetry estimates derived from sequential whole-body PET using two versions of the OLINDA dosimetry program. Methods Sequential whole-body PET scans were performed in 3 healthy subjects for 2 h after injection of 254 ± 77 MBq [ 11 C]-UCB-J. Volumes of interest were drawn over relevant source organs to generate time-activity curves and calculate time-integrated activity coefficients, with effective dose coefficients calculated using OLINDA 2.1 and compared to values derived from OLINDA 1.1 and those recently reported in the literature. Results [ 11 C]-UCB-J administration was safe and showed mixed renal and hepatobiliary clearance, with largest organ absorbed dose coefficients for the urinary bladder wall and small intestine (21.7 and 23.5 μGy/MBq, respectively). The average (±SD) effective dose coefficient was 5.4 ± 0.7 and 5.1 ± 0.8 μSv/MBq for OLINDA versions 1.1 and 2.1 respectively. Doses were lower than previously reported in the literature using either software version. Conclusions A single IV administration of 370 MBq [ 11 C]-UCB-J corresponds to an effective dose of less than 2.0 mSv, enabling multiple PET examinations to be carried out in the same subject. Trial registration EudraCT number: 2016-001190-32. Registered 16 March 2016, no URL available for phase 1 trials.