RT Journal Article
SR Electronic
T1 In vivo comparison of tau radioligands <sup>18</sup>F-THK-5351 and <sup>18</sup>F-THK-5317
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP jnumed.116.182980
DO 10.2967/jnumed.116.182980
A1 Betthauser, Tobey
A1 Lao, Patrick J
A1 Murali, Dhanabalan
A1 Barnhart, Todd E
A1 Furumoto, Shozo
A1 Okamura, Nobuyuki
A1 Stone, Charles K
A1 Johnson, Sterling C
A1 Christian, Bradley T
YR 2016
UL http://jnm.snmjournals.org/content/early/2016/11/16/jnumed.116.182980.abstract
AB Purpose This study compared the in vivo imaging characteristics of tau positron emission tomography (PET) ligands 18 F-THK-5351 and 18F-THK-5317 in the context of Alzheimer’s disease (AD). Additionally, reference tissue distribution volume ratio (DVR) estimation methods and standard uptake value ratio (SUVR) timing windows were evaluated to determine the optimal strategy for specific binding quantification. Methods Twenty-eight subjects (mean age 71±7yrs) underwent either dynamic 90-minute 18F-THK-5317 or 18F-THK-5351 PET scans. Bland-Altman plots were utilized to compare the simplified reference tissue method (SRTM), multilinear reference tissue method (MRTM2), and Logan reference tissue DVR estimates and to assess temporal stability of SUVR windows using cerebellar gray matter (GM) as a reference region. In vivo kinetics and DVR estimates were directly compared for 10 subjects that underwent both 18F-THK-5317 and 18F-THK-5351 PET scans. Results THK-5351 exhibited faster cerebellar GM clearance, faster cortical white matter (WM) clearance, and higher DVR estimates in AD tau-associated regions of interest (ROIs) compared to THK-5317. The MRTM2 method produced the most reliable DVR estimates for both tracers, particularly when scan duration was shortened to 60 minutes. SUVR stability was observed 50-70 minutes post injection for both tracers. Parametric images revealed differences between MRTM2, Logan and SUVR binding in WM regions for THK-5317. Conclusion THK-5317 and THK-5351 show promise for in vivo detection of AD tau. THK-5351 has more favorable pharmacokinetics and imaging characteristics compared to THK-5317.