LOS ANGELES - A new brain imaging agent shows promise for detecting and tracking progressive supranuclear palsy (PSP), a rare and debilitating brain disease, according to research shared May 30 at the Society of Nuclear Medicine and Molecular Imaging (SNMMI) meeting.
The tracer, called [F-18] OXD-2314, successfully identified abnormal protein buildup in key brain regions of patients with PSP -- good news, as "conventional radiotracers often show low affinity for non-Alzheimer's disease tau isoforms," said presenter Lucas Narciso, PhD, of Canada's Centre for Addiction and Mental Health (CAMH).
Lucas Narciso, PhDAuntMinnie
Progressive supranuclear palsy (PSP) is a neurodegenerative tauopathy characterized by the accumulation of tau protein, Narciso explained. Unlike Alzheimer's disease, which also involves tau, PSP manifests a specific form of the protein that has proven difficult to image with existing tools, he said. He and colleagues specifically designed [F-18] OXD-2314 to detect this type of tau, making it a potentially important advance for patients who currently have no reliable imaging biomarker to confirm their diagnosis or track disease changes over time.
To evaluate the performance of the tracer, researchers conducted a study that consisted of nine healthy controls and five individuals with PSP who underwent 120-minute PET/CT exams after administration of 190 MBq of [F-18] OXD-2314; arterial sampling was performed throughout these exams for five healthy participants and three PSP patients. Study participants also underwent an MRI exam to capture anatomical data.
Narciso's group found that patients with PSP showed elevated tracer activity in several deep brain structures, including the basal ganglia, the dentate nucleus, and the substantia nigra -- areas known to be heavily affected by PSP. Compared to healthy volunteers, PSP patients showed between 6% and 14% higher signal in these regions, depending on the measurement method used. Despite the modest percentage differences, the effect sizes were considered large, suggesting the signal is meaningful even in a small study population.
Lucas Narciso, PhD, and SNMMI
The takeaway? [F-18] OXD-2314 PET "demonstrates high potential as a biomarker of [tau] progression and evaluating therapeutic efficacy," Narciso concluded.
Check out AuntMinnie’s full coverage of SNMMI 2026 on our ShowCast.
