68Ga-P15-041 and 68Ga-PSMA-11 PET/CT Imaging in the Same Group of Prostate Bone Metastasis

Tumor bone metastasis refers to the metastasis of malignant tumors to the bone through lymph, blood or direct invasion to generate daughter tumors, which is the most common bone tumor. More than 40% of patients with malignant tumors will have bone metastasis, among which breast cancer, prostate cancer is more common, once the tumor cells occur bone metastasis, it means that the disease enters the advanced stage, posing a serious threat to the life safety of patients, therefore, early diagnosis of various primary malignant tumor bone metastases, can lay the foundation for clinical implementation of effective treatment measures. The laboratory of Hank F. Kung at the University of Pennsylvania has developed a new generation of 68Ga-labeled radiopharmaceutical P15-041 (\[68Ga\]Ga-HBED-CC-BP) based on existing phosphonate-targeting molecular probes (Figure 1). Data from preclinical studies indicate that P15-041 shows additional advantages in rapid and easy complex formation compared to current \[68Ga\]Ga-BPAMD, \[68Ga\]Ga-NO2AP-BP, \[68Ga\]Ga-DOTA- (ZOL). In vivo experiments, P15-041 showed good bone resorption and rapid renal excretion in normal mice. Haiyan Hong et al. \[13\] prepared multiple clinical doses of P15-041 and successfully evaluated it in patients, followed by intravenous P15-041, followed by a whole body PET/CT scan. Robert K. Doot et al. conducted dosimetric experiments on P15-041, analyzed the radioactive distribution of the drug in normal organs and the dynamic change of the dose of the drug in the body over time, and the results showed that P15-041 had high uptake in the bladder wall and bone cortex, blood and other tissues cleared quickly, and there was obvious radioactive enrichment in the myocardium in the early stage of imaging, and P15-041 had the potential to become a new generation of excellent phosphonate molecular probes.