Amyloid plaque imaging from IMPY/SPECT to AV-45/PET

Area of Science:

• Neuroimaging
• Neuropathology
• Molecular Imaging

Background:

• Beta-amyloid (Aβ) plaque formation is an early hallmark of Alzheimer's disease (AD).
• Molecular imaging offers a noninvasive method to visualize Aβ plaques, aiding early diagnosis and neuropathogenesis research.
• Radionuclide-labeled ligands for PET and SPECT imaging of Aβ plaques have advanced significantly.

Purpose of the Study:

• To review the development and application of Aβ-targeting radiotracers for Alzheimer's disease imaging.
• To discuss the role of AV-45 as a standard PET imaging agent in clinical trials.
• To present experiences with Aβ-targeting radiotracers at Chang Gung University and Chang Gung Memorial Hospital.

Main Methods:

• Review of clinical trial data and published studies on AV-45 and other Aβ-targeting radiotracers.
• Analysis of "imaging to autopsy" studies validating plaque burden correlation.
• Consensus decisions by the Alzheimer's Disease Neuroimaging Initiative (ADNI) regarding AV-45 standardization.

Main Results:

• AV-45 was the first plaque imaging agent in US multi-center clinical trials, studied in over 1,000 subjects.
• "Imaging to autopsy" studies confirmed the correlation between imaging signals and actual plaque burden.
• AV-45 is recognized by ADNI as a standard PET imaging agent for evaluating plaque progression across cognitive states.

Conclusions:

• AV-45 is a validated and promising imaging agent for Alzheimer's disease pathology.
• Standardization of AV-45 facilitates global clinical trials for disease detection and progression monitoring.
• Continued research and application of Aβ-targeting radiotracers are essential for advancing AD understanding and treatment.