English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Background  Both enantiomers of [ 18 F]flubatine are new radioligands for neuroimaging of α 4 β 2  nicotinic acetylcholine receptors with positron emission tomography (PET) exhibiting promising pharmacokinetics which makes them attractive for different clinical questions. In a previous preclinical study, the main advantage of (+)-[ 18 F]flubatine compared to (−)-[ 18 F]flubatine was its higher binding affinity suggesting that (+)-[ 18 F]flubatine might be able to detect also slight reductions of α 4 β 2  nAChRs and could be more sensitive than (−)-[ 18 F]flubatine in early stages of Alzheimer’s disease. To support the clinical translation, we investigated a fully image-based internal dosimetry approach for (+)-[ 18 F]flubatine, comparing mouse data collected on a preclinical PET/MRI system to piglet and first-in-human data acquired on a clinical PET/CT system. Time-activity curves (TACs) were obtained from the three species, the animal data extrapolated to human scale, exponentially fitted and the organ doses (OD), and effective dose (ED) calculated with OLINDA.    Results  The excreting organs (urinary bladder, kidneys, and liver) receive the highest organ doses in all species. Hence, a renal/hepatobiliary excretion pathway can be assumed. In addition, the ED conversion factors of 12.1 μSv/MBq (mice), 14.3 μSv/MBq (piglets), and 23.0 μSv/MBq (humans) were calculated which are well within the order of magnitude as known from other  18 F-labeled radiotracers.    Conclusions  Although both enantiomers of [ 18 F]flubatine exhibit different binding kinetics in the brain due to the respective affinities, the effective dose revealed no enantiomer-specific differences among the investigated species. The preclinical dosimetry and biodistribution of (+)-[ 18 F]flubatine was shown and the feasibility of a dose assessment based on image data acquired on a small animal PET/MR and a clinical PET/CT was demonstrated. Additionally, the first-in-human study confirmed the tolerability of the radiation risk of (+)-[ 18 F]flubatine imaging which is well within the range as caused by other  18 F-labeled tracers. However, as shown in previous studies, the ED in humans is underestimated by up to 50 % using preclinical imaging for internal dosimetry. This fact needs to be considered when applying for first-in-human studies based on preclinical biokinetic data scaled to human anatomy.    Electronic supplementary material  The online version of this article (doi:10.1186/s40658-016-0160-5) contains supplementary material, which is available to authorized users.

ejnmmi physics

Radiation dosimetry of the α4β2 nicotinic receptor ligand (+)-[18F]flubatine, comparing preclinical PET/MRI and PET/CT to first-in-human PET/CT results