18F-S2P PET Imaging in the Evaluation of Large Artery Atherosclerosis

A Prospective Clinical Study of 18F-S2P-Targeted STAB2 Receptor PET Imaging in the Diagnosis of Large Artery Atherosclerosis

The aim of this study is to evaluate the lesion detection performance and safety of 18F-S2P positron emission tomography (PET) in patients with large-artery atherosclerosis.

Atherosclerotic lesions contain macrophages expressing stabilin-2 (STAB2), which can be targeted by 18F-S2P. However, conventional vascular imaging modalities mainly reflect the anatomical characteristics of atherosclerotic lesions and have limited ability to assess plaque inflammatory activity, which may affect the identification and risk evaluation of vulnerable plaques. In addition, routine vascular imaging lacks specific molecular biomarkers for evaluating plaque inflammation. 18F-S2P is a novel 18F-labeled peptide tracer targeting STAB2. Preclinical data suggest that 18F-S2P has favorable biodistribution and lesion-targeting properties, with no apparent toxicity observed in animal studies. Patients can undergo PET imaging 0.5 hours after injection without special preparation. Our study will assess the safety profile, image quality, and lesion detection performance of 18F-S2P. Patients with clinically suspected large-artery atherosclerosis will be enrolled in this study.

Inclusion Criteria

1. Aged 40 to 80 years old;
2. Clinically suspected large artery atherosclerosis;
3. Able to understand and comply with all study requirements;
4. Participants aged ≥65 years with full civil capacity may sign informed consent independently; those with limited civil capacity shall sign the informed consent together with their legal guardians.

Exclusion Criteria

1. Pregnant or breastfeeding female patients;
2. Patients with severe claustrophobia, radiophobia, mental disorders or primary emotional disorders;
3. Abnormal laboratory indicators at screening: hemoglobin (Hb) <10 g/dL, white blood cell (WBC) <3×10^9/L, platelet (PLT) <90×10^9/L, or creatinine clearance (CrCl) <40 mL/min;
4. Subjects received ionizing radiation outside this trial within the past year leading to an annual radiation exposure exceeding 50 mSv;
5. Subjects received any investigational drugs or devices with unconfirmed safety/efficacy within one month before enrollment;
6. Any condition judged by the principal investigator that may bring potential harm to participants during the trial.