Head-to-Head Comparison of 11C-PiB and 18F-AZD4694 (NAV4694) for β-Amyloid Imaging in Aging and Dementia

Journal of Nuclear Medicine

Victor L. Villemagne¹  Zsolt Cselényi¹  J. Gordon Chan¹  Colin L. Masters¹  Rachel S. Mulligan¹  Svetlana Pejoska¹  Samuel Svensson¹  Gareth Jones¹  Christopher C. Rowe¹ 

关键词: Alzheimer’s disease;    amyloid imaging;    Aβ;    positron emission tomography;   

DOI  :  10.2967/jnumed.112.114785

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

11C-Pittsburgh compound-B (11C-PiB) is the benchmark radiotracer for imaging of β-amyloid (Aβ) plaque in Alzheimer disease (AD). 18F-labeled Aβ tracers subsequently developed for clinical use show higher nonspecific white matter binding and, in some cases, lower cortical binding in AD that could lead to less accurate interpretation of scans. We compared the cortical and white matter binding of a new 18F-labeled Aβ tracer, 18F-AZD4694 (recently renamed NAV4694), with 11C-PiB in the same subjects. Methods: Forty-five participants underwent PET imaging with 11C-PiB and 18F-AZD4694 (25 healthy elderly controls [HCs], 10 subjects with mild cognitive impairment, 7 subjects with probable AD, and 3 subjects with probable frontotemporal dementia). Images were coregistered so that region-of-interest placement was identical on both scans, and standardized uptake value ratios (SUVRs) using the cerebellar cortex as a reference region were calculated between 40 and 70 min after injection for both tracers. Results: 18F-AZD4694 showed reversible binding kinetics similar to 11C-PiB, reaching an apparent steady state at 50 min after injection. Both radiotracers showed a similar dynamic range of neocortical SUVR (1.1–3.3 and 1.0–3.2 SUVR for 11C-PiB and 18F-AZD4694, respectively) and identical low nonspecific white matter binding, with frontal cortex–to–white matter ratios of 0.7 ± 0.2 and 1.3 ± 0.2 for both radiotracers in HCs and AD subjects, respectively. There was an excellent linear correlation between 11C-PiB and 18F-AZD4694 neocortical SUVR (slope of 0.95, r = 0.99, P < 0.0001). Conclusion: 18F-AZD4694 displays imaging characteristics nearly identical to those of 11C-PiB. The low white matter and high cortical binding in AD indicate that this tracer is well suited to both clinical and research use.

【 授权许可】

Unknown