Intranasal Delivery of Brain PET Tracer Makes First Appearance in Human Trials

In a significant breakthrough, a recent study has confirmed the safety and efficacy of Gallium-68 NOTA-insulin as a Positron Emission Tomography (PET) radiotracer for assessing intranasal delivery of insulin to the brain in humans. The study, published in Alzheimer's & Dementia: Translational Research & Clinical Interventions, was conducted using a Discovery MI DR PET scanner manufactured by GE HealthCare.

The study, which assessed the technique for the first time in humans, involved seventeen participants, seven of whom were cognitively normal (CN), and nine who had mild cognitive impairment (MCI). Participants received a spray of Ga-68 NOTA-insulin into each nostril three times with thirty seconds between each set. Within five minutes of the final spray, participants underwent a dynamic 40-minute brain PET scan.

The observations made in the study suggest that brain uptake and distribution of intranasally delivered substances may differ for adults with MCI. Distinct tracer uptake patterns were observed between the CN and MCI groups. Mean insulin standardized uptake values (SUVs) were higher for cognitively normal participants than for participants with MCI in the hippocampus, parahippocampus, amygdala, olfactory cortex, and thalamus.

Intriguingly, peak uptake occurred at approximately 750 seconds in all regions for the CN group, except for the cingulum, which peaked at 150 seconds. Conversely, the MCI group peaked at approximately 150 seconds across all regions, suggesting altered tracer uptake. Furthermore, a faster radiotracer clearance rate was observed in the MCI relative to the CN group.

Brain insulin signaling has been linked to memory function, and intranasal insulin (INI) has been shown to improve functional ability and cognition in Alzheimer's disease patients in clinical trials. The study provides critical information to guide future studies of INI as a treatment for MCI and Alzheimer's disease.

Interestingly, there are no search results directly identifying specific research groups that have studied and published on the safety and efficacy of Gallium-68 NOTA-Insulin as a PET radiotracer for intranasal insulin delivery to the human brain. The study provides a means of validating intranasal delivery devices.

The full study is available for access, offering an exciting opportunity for researchers and healthcare professionals to delve deeper into the potential of Ga-68 NOTA-insulin as a tool for neuroimaging and the treatment of cognitive impairments.