Infection Imaging With 18F-FDS and First-in-Human Evaluation

Abstract

PurposeThe noninvasive imaging of bacterial infections is critical in order to reduce mortality and morbidity caused by these diseases. The recently reported 18F-FDS (18F-2-fluorodeoxy sorbitol) as a PET (positron emission tomography) tracer can be used to image Enterobacteriaceae-specific infections and provides a potential alternative to this problem compared with other probes for imaging infections. In this study, automatic synthesis, validation of 18F-FDS and a first-in-human study were performed and discussed. MethodsA multifunctional synthesis module was employed for the radiosynthesis of 18F-FDG (18F-2-fluorodeoxy glucose) and 18F-FDS starting from 18F ion using two-pot three-step fully automated reactions. The behavior of 18F-FDS as an in vivo imaging probe for infections was evaluated in an Escherichia coli mouse infection model. The first detailed pharmacokinetic and biodistribution parameters were obtained from healthy human volunteers. ResultsThe uptake of 18F-FDS in an E. coli mouse-myositis infection model was easily differentiated from other organs and normal muscle. Intensive lesion uptake declined after antibiotic treatment. In the pilot human study, no adverse effects due to 18F-FDS were observed up to 24h post-injection. The radiotracer was rapidly cleared from the circulation and excreted mainly through the urinary system. ConclusionWe conclude that 18F-FDS PET holds great potential for appropriate and effective for the imaging of bacterial infections in vivo. These preliminary results indicate that further clinical studies are warranted.