First-in-human study of the radioligand 68Ga-N188 targeting nectin-4 for PET/CT imaging of advanced urothelial carcinoma

• Published in: Clinical cancer research 2023-09, Vol.29 (17), p.3395-3407
• Main Authors: Duan, Xiaojiang, Xia, Lei, Zhang, Zhuochen, Ren, Yanan, Pomper, Martin G, Rowe, Steven P, Li, Xuesong, Li, Nan, Zhang, Ning, Zhu, Hua, Yang, Zhi, Sheng, Xinan, Yang, Xing
• Format: Article
• Language: English
• ISSN: 1078-0432; 1557-3265
• DOI: 10.1158/1078-0432.CCR-23-0609

Nectin-4 is an emerging biomarker for cancer diagnosis and therapy. Recently, enfortumab vedotin (EV) was approved by the FDA as the first nectin-4 targeting antibody-drug conjugate for treating advanced urothelial carcinoma. A PET imaging method to non-invasively quantify nectin-4 expression level would potentially help to select patients most likely to respond to EV and predict the response. In this study, we designed a bicyclic peptide-based nectin-4 targeting radiotracer 68Ga-N188. Initially, we performed preclinical evaluations of 68Ga-N188 in urothelial cancer cell lines and xenograft mouse models. Next, we performed the translational study in healthy volunteers and a pilot cohort of patients with advanced urothelial cancer on uEXPLORER total-body PET/CT. In the preclinical study, 68Ga-N188 showed high affinity to nectin-4, specific uptake in a nectin-4(+) xenograft mouse model, suitable pharmacokinetic and safety profiles. In the translational study, two healthy volunteers and fourteen patients with advanced urothelial cancer were enrolled in the translational study. The pharmacokinetic profile was determined for 68Ga-N188, and the nectin-4 relative expression level in different organs was quantitatively imaged. A clear correlation between PET SUV value and nectin-4 expression was observed, supporting the application of 68Ga-N188 PET as a companion diagnostic tool for optimizing treatments that target nectin-4.