(UroToday.com) The 2025 SNMMI annual meeting featured a discovery and translational session and a presentation by Dr. Wenjia Zhu discussing a preliminary study of 68Ga-NYM096 PET/CT in patients with metastatic clear cell renal cell carcinoma (RCC). NYM096 is a new generation carbonic anhydrase 9 (CA9) targeting small molecule, which can be labeled with both 68Ga and 177Lu. It has higher affinity (almost 100-fold) to CA9 compared to NYM005. In this study presented at SNMMI 2025, Dr. Zhu and colleagues aimed to evaluate its performance in patients with metastatic clear cell RCC.
Patients with metastatic clear cell RCC were prospectively recruited in the study. A wash-out of 7 days was required if the patients were on tyrosine kinase inhibitors. All patients received an intravenous injection of 68Ga-NYM096 and underwent whole body PET/CT scan using a total-body PET/CT scanner at 60 min after injection. In one patient, multi-time-point scans were performed to estimate the dosimetry. In some patients, 18F-FDG PET/CT was also performed within one week before or after 68Ga-NYM096 PET/CT. The biodistribution of 68Ga-NYM096 in normal organs was evaluated, and the tumor uptake and tumor-to-background ratio were also recorded and compared to that of 18F-FDG.
A total of 21 patients (18 men with a mean age of 61.5 ± 13.3 years) were recruited in this preliminary study. All patients had 68Ga-NYM096 PET/CT, and 19 patients also had 18F-FDG PET/CT. Intensive uptake was noted in the stomach, kidney, and pancreas, with SUVmax of 68.5 ± 29.0, 29.5 ± 7.9, and 25.0 ± 8.8, respectively. Substantial uptake was also noted in the intestine, whereas the brain did not show significant tracer accumulation, and mild uptake was observed in the choroid plexus. The investigators also found mild symmetrical uptake in the epididymis, which is consistent with physiological CA9 expression in this organ.
In one patient, total body scans were performed at 15 minutes, 1 hour, 2 hours, and 4 hours post-injection. The effective dose was 0.022 mSv/MBq, with the stomach wall receiving the highest organ dose at 0.091 mSv/MBq, followed by the kidney at 0.118 mSv/MBq. All patients had positive lesions on 68Ga-NYM096 PET/CT:
The SUVmax of the hottest lesion in each patient ranged from 11 to 300 in all patients, with a mean SUVmax of 115.0 ± 70.6, which was significantly higher than that of 18F-FDG (11.1 ± 9.1, p＜0.001). The tumor-to-blood-pool ratio was also higher (102.6 ± 77.4 versus 6.6 ± 5.9, p＜0.001).
Dr. Zhu concluded this presentation discussing a preliminary study of 68Ga-NYM096 PET/CT in patients with metastatic clear cell RCC with the following take home points:
- The new generation CA9 PET tracer 68Ga-NYM096 shows remarkable uptake in clear cell RCC
- Taken together with its reassuring dosimetry profile, this tracer holds potential for improved clear cell RCC imaging
Presented by: Wenjia Zhu, Peking Union Medical College Hospital, Beijing, China
Written by: Zachary Klaassen, MD, MSc – Urologic Oncologist, Associate Professor of Urology, Georgia Cancer Center, Wellstar MCG Health, @zklaassen_md on Twitter during the 2025 Society of Nuclear Medicine and Molecular Imaging (SNMMI) Annual Meeting, New Orleans, LA, June 21st – 24th, 2025