Klunk, W. E. & Mathis, C. A. The future of amyloid-beta imaging: a tale of radionuclides and tracer proliferation. Curr. Opin. Neurol. 21, 683-687

Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
Current Opinion in Neurology (Impact Factor: 5.31). 01/2009; 21(6):683-7. DOI: 10.1097/WCO.0b013e3283168e1a
Source: PubMed


This review will focus on the coming proliferation of amyloid-beta imaging tracers and give an opinion on how the Alzheimer's disease field can develop a systematic means of evaluating which tracers are useful and how the useful tracers compare to each other.
Several new tracers have been reported to be useful for human amyloid-beta imaging. The most recent of these are labeled with fluorine-18. Compared with the 20 min half-life of carbon-11 used in the most widely used tracer, Pittsburgh Compound-B, the 110 min half-life of fluorine-18 allows for wider utilization in research and clinical settings.
It is likely that more than one fluorine-18-labeled tracer will come into common use. The use of preclinical and clinical 'bridging studies' to [C-11]Pittsburgh Compound-B could be a means to determine whether the sizable body of knowledge already gained in [C-11]Pittsburgh Compound-B studies can be applied to the understanding of these new tracers and to form a basis for the comparison among them. This approach could save resources and help sort out a potentially bewildering onslaught of new amyloid-beta imaging tracers.

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    • "Neuroimaging biomarkers provide prognostic value for conversion from MCI to AD, because MCI patients who are Ab positive are highly likely to progress, whereas those who are Ab negative are not [18] [19]. A major limitation to Pittsburgh compound B is its short half-life (about 20 minutes), which limits a broader application [20], but is not as significant of a limitation with florbetapir F18 [21]. Positron emission tomography (PET) is cost prohibitive in routine settings, including screening into clinical trials. "
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    • "Tel.: +310 825 0291; +Fax: 310 825 3910; E-mail: first carbon-11-labeled PET radiotracer intended for human in vivo amyloid-beta imaging known as Pittsburgh Compound-B (PIB) was presented in preliminary form in 2002, with the full report in 2004 (see [9] for review) 1 . "
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