On May 12, 2025, RemeGen Co., Ltd. (“RemeGen”, stock symbols: 688331.SH/09995.HK) announced that its phase 3 clinical trial (NCT05302284, study ID: RC48-C016) on disitamab vedotin (DV, brand name: Aidixi®), an anti-HER2 antibody-drug conjugate (ADC), in combination with the PD-1 inhibitor toripalimab versus the standard chemotherapy as a first-line treatment for HER2-expressing locally advanced or metastatic urothelial carcinoma (la/mUC) has reached its primary endpoints of progression-free survival (PFS) and overall survival (OS). Statistically significant and clinically meaningful benefits were observed from the strongly positive results of a prespecified interim analysis by Independent Data Monitoring Committee (IDMC). The primary subgroup analysis showed that DV combined with toripalimab significantly improved PFS and OS compared with the standard chemotherapy of la/mUC, irrespective of cisplatin eligibility or HER2 expression level. Furthermore, this regimen exhibited manageable safety profile and tolerable adverse reactions. Detailed data of this study will be presented at major international academic conferences later this year. RemeGen plans to file Biologic License Application (BLA) submission for this indication to the Center of Drug Evaluation of National Medical Products Administration (NMPA) in China.

RC48-C016 is a randomized, active-control, multi-center phase 3 clinical trial evaluating efficacy and safety of DV plus toripalimab versus gemcitabine in combination with cisplatin/carboplatin in systemic-treatment-naive patients with HER2-expressing (defined as IHC 1+, 2+ or 3+) la/mUC. The study was initiated in June 2022 and conducted in 74 sites across China with 484 patients enrolled, the contribution of the investigators and patients is greatly appreciated.

“The strongly positive results of DV in combination with toripalimab as a first-line treatment for advanced urothelial carcinoma are encouraging. DV combined with toripalimab significantly improved PFS and OS, irrespective of cisplatin eligibility or HER2 expression level, which proves the success of HER2-ADC plus immunotherapy and represents a major breakthrough in the treatment of urothelial carcinoma worldwide. It is expected that the excellent performance of disitamab vedotin in subsequent studies will provide better decision-making basis for clinicians, bring more benefits to patients, and reshape the global treatment landscape of urothelial carcinoma with the Chinese regimen,”said Dr. Jun Guo, principal investigator of the study and professor at Peking University Cancer Hospital.

About Disitamab Vedotin

DV is the first novel ADC initially developed by a Chinese company and have been granted conditional approval by NMPA for treatment of gastric cancer and la/mUC in China.