Mabwell (Shanghai) Bioscience Co., Ltd. announced the progress of the clinical study of its novel Nectin-4-targeting ADC (R&D code: 9MW2821) for triple-negative breast cancer. Based on 9MW2821's current ongoing monotherapy clinical data, in 20 subjects with locally advanced or metastatic triple-negative breast cancer treated with the 1.25 mg/kg dose and evaluable for tumor assessment, the objective response rate (ORR) and disease control rate (DCR) were 50% and 80%, respectively, with one patient achieved CR and had been in complete response (CR) for 20 months and is currently sustained to be CR. Investigational new drug application of 9MW2821 in combination with immune checkpoint inhibitor for the treatment of triple-negative breast cancer has been accepted by the China National Medical Products Administration (NMPA).

9MW2821 is currently undergoing clinical studies across multiple indications. Phase III monotherapy study of locally advanced/metastatic urothelial carcinoma on patients previously treated with platinum-based chemotherapy and PD-(L)1 inhibitor has formally initiated; A Phase I/II study evaluating first-line combination therapy options with a PD-1 inhibitor has also begun. The first patient enrollment for the two studies were both completed.

For cervical cancer and esophageal cancer, Mabwell is actively seeking for Phase III clinical trial approval, and additionally conducting scientific assessments of front-line combination regimens, with clinical trial application expected to be submitted soon. 9MW2821 has been granted Fast Track Designation (FTD) and Orphan Drug Designation (ODD) by the U.S. Food and Drug Administration for the treatment of advanced, recurrent, or metastatic esophageal squamous cell carcinoma and esophageal cancer, respectively.