Description:

Multiple myeloma (MM) commonly occurs in the elderly and often remains undetected until it reaches an advanced stage. With the aging population in China, the incidence of MM is on the rise, now surpassing that of acute leukemia. Clinically, MM is characterized by bone destruction and lacks specificity; diagnosis primarily relies on bone marrow biopsies that detect an increase in clonal plasma cells, which are invasive and can yield false-negative results if the biopsy site is improperly selected. CD38 is significantly overexpressed on the surface of malignant plasma cells in MM, making it a characteristic tumor biomarker for MM. As the incidence of malignant tumors in China continues to increase, so does the clinical demand for radiopharmaceuticals. Addressing the limitations in the targeting of 18F-FDG in PET imaging, the development of new targeted nuclear medicine molecular probes is of significant academic value and clinical importance, particularly in monitoring the therapeutic effects of the CD38-targeted nanobody NB381, which offers unique advantages. This project uses a nanobody with high affinity for CD38 as the targeting moiety for the radiopharmaceutical, exploring the diagnostic efficiency of 68Ga-NB381 in patients with MM exhibiting high CD38 expression. This not only provides a basis for the early diagnosis of MM but also allows for the formulation of effective precision treatment strategies based on the CD38 expression profile in MM patients. 68Ga-NB381, a new CD38-targeted molecular probe labeled with 68Ga, can be used for the diagnosis and research of various malignancies expressing high levels of CD38, including MM. The probe is conjugated with 68Ga3+ using TOHP as a bifunctional chelator, with a simple labeling process that does not require purification, offering high in-vivo stability and significant radioactive accumulation in tumor sites in mouse models, resulting in superior imaging outcomes. This project will complete the automation of the 68Ga-NB381 labeling process and conduct quality control studies on the resulting radiopharmaceutical injection solution, establishing quality standards for this new PET probe and laying the foundation for its clinical translation in China. The project aims to provide 68Ga-NB381 PET/CT imaging studies to support the early diagnosis of CD38 high-expression malignancies, the formulation of treatment plans, and the assessment of therapeutic efficacy.