A clinically developed novel PET radiotracer may be effective for stratifying patients with hypertension and suspected Conn's syndrome to avoid unnecessary adrenal vein sampling, suggest findings presented June 1 at the 2026 Society of Nuclear Medicine and Molecular Imaging (SNMMI) annual meeting in Los Angeles.
Researchers at the University of Michigan reported on the first-in-human study of a sterol o-acyl transferase 1 (SOAT1)-targeted PET radiotracer called carbon-11 (C-11) nevanimibe, validating its effectiveness in imaging overactive adrenal glands. The research could help clinicians better identify ways to diagnose and treat primary aldosteronism (PA), also known as Conn's syndrome.
Primary aldosteronism represents the largest fraction of patients with curable secondary hypertension. The adrenal gland overproduces aldosterone from cholesterol which then artificially increases blood pressure.
“By using a PET radiotracer that targets cholesterol metabolism in the adrenal glands, physicians can noninvasively identify overactive glands to guide clinical decision making," stated Peter Scott, PhD, from the University of Michigan Ann Arbor.
Led by Benjamin Viglianti, MD, PhD, the initial study involved dosing nine patients with 8-10 mCi of nevanimibe C-11 and imaging (Siemens Healthineers Biograph PET-CT) from zero to 60 minutes post-injection, followed by a static PET/CT image at 60 minutes.
The study included six healthy controls and three patients who were previously diagnosed with overactive adrenal glands, via an elevated urine free cortisol test and failure to respond to adrenal suppression with dexamethasone phosphate.
Researchers compared maximum standardized uptake values (SUVmax) of the radiotracer in both the liver and the adrenal glands between patients with adrenal pathology and the healthy controls.
Static PET-CT image of patient with hypercortisolism taken at 60 minutes post-injection. Peter Scott, PhD, and SNMMI
According to initial data, the adrenal-to-liver uptake ratio in patients with overactive adrenal glands displayed an average SUVmax of 1.2 compared to 0.7 in control subjects. Overall, the human biodistribution of nevanimibe C-11 closely mirrored preclinical findings, supporting successful translation to clinical use, Viglianti and colleagues found.
The group also noted the following:
- A significant difference in lateral uptake in the adrenal glands of patients with hypercortisolism has not yet been observed.
- Images displayed tracer accumulation in bone which coincides with SOAT1 expression in macrophages in the bone marrow.
- Lack of uptake in the bladder is consistent with the hypothesis that the high LogP of the tracer (6.63) leads to biliary excretion.
- Abnormally high focal uptake was observed in two of these clinical studies and can be attributed to the increased SOAT1 expression in sebaceous glands.
"We have translated a preclinically developed tracer into clinical studies and assessed its initial kinetics in patients with hyperactive adrenal glands," wrote Viglianti and colleagues. This initial data suggests that SOAT1 imaging may be used to stratify patients with hypertension and suspected PA to avoid unnecessary invasive screening involving adrenal vein sampling at specialized facilities.
Additional clinical studies are underway to study dosimetry and efficacy.
Check out AuntMinnie’s full coverage of SNMMI 2026 on our ShowCast.
