Navidea Biopharmaceuticals, Inc. (AMEX: NAVB) announced the peer-reviewed publication of results from a clinical trial of NAV4694 in healthy subjects and those with diagnosed forms of dementia. The trial assessed the performance of Navidea s Fluorine-18 labeled amyloid imaging candidate, NAV4694, in a head-to-head comparison with the acknowledged benchmark, gold-standard amyloid imaging agent, 11C-labeled Pittsburgh Compound-B (PiB). Results demonstrated that NAV4694 displayed imaging characteristics nearly identical to those of PiB and the authors believe these results show that NAV4694 may be useful in the early and differential diagnosis of Alzheimer s disease (AD). The study, Head-to-Head Comparison of 11C-PiB and 18F-AZD4694 (NAV4694) for -Amyloid Imaging in Aging and Dementia, was published in the current online edition of the Journal of Nuclear Medicine and will appear in the June print edition [J Nucl Med 2013; 54:1 "7 DOI: 10.2967/jnumed.112.114785].
-Amyloid imaging has the potential to play an increasingly important role in clinical practice as revised criteria for the diagnosis of probable AD allow for earlier diagnosis and therapeutic intervention. For this to be a reality, clinicians will need access to reliable, practical and affordable imaging options, said Professor Christopher Rowe, MD, FRACP, Director of the Department of Nuclear Medicine and Centre for PET at Austin Health, Melbourne, Australia and one of the authors. This study suggests that NAV4694 images may be more easily and reliably read in clinical practice than other F-18 labeled PET tracers. By displaying imaging characteristics nearly identical to those of the gold standard, PiB, NAV4694 provides the same low background needed for earlier differential diagnosis while affording the practicality needed for production logistics.
With the ongoing movement toward earlier evaluation and treatment of cognitive impairment, it is of increasing importance for an improved diagnostic tool that ca
think the advantage comes from the radio half life of F18 vs. C11...C11 half life is 20 min, vs. 110 min for F18.
here's a partial post from the IV forum:
"Amyloid imaging is now promising earlier Alzheimer’s disease diagnoses and potential anti-amyloid therapies in the not-too-distant future. The radiotracer C-11 Pittsburgh compound-B (C-11 PiB) has been proven effective for amyloid PET imaging and has outperformed many F-18 bound biomarkers, but the radiotracer F-18 NAV4694 is showing a binding pattern that nearly mirrors that of C-11 PiB with all the logistical perks of a fluorine-based agent, according to research being published in the June edition of The Journal of Nuclear Medicine.
Christopher C. Rowe, MD, a professor of nuclear medicine at Austin Health in Melbourne, Australia, and colleagues, conducted a head-to-head comparison of C-11 PiB and F-18 NAV4694 PET radiotracers to determine how they imaged amyloid plaque in the brain both visually and quantitatively.
A range of F-18 based amyloid imaging agents have been developed, including Florbetapir, as well as other phase III investigational agents florbetaben and flutemetamol, but C-11 PiB has typically shown stronger cortical binding than F-18 conjugated biomarkers, which also tend to bind to more non-specific white matter. Amyloid binding in white matter is not associated with Alzheimer’s pathology and can complicate visual interpretation. However, expansion of C-11 PiB is limited by production logistics. Due to its radioactive half-life of 20 minutes, C-11 PiB requires an on-site cyclotron, whereas F-18 radiotracers have a 110 minute half-life much more conducive for commercialization and distribution.
F-18 NAV4694, previously named AZD4694, has a chemical structure similar to C-11 PiB. This is the first study of its kind comparing the two biomarkers. Results of the study raised the bar for F-18 amyloid imaging tracers, with F-18 NAV4694 landing at the top of the heap.....