According to the Zhitong Finance App, Maiwei Bio-B (02493) announced that the company will announce phase II clinical study data on patients with locally advanced or metastatic triple-negative breast cancer (TNBC) in the form of an oral report at the 2026 European Society of Medical Oncology (ESMO) conference to be held in Madrid, Spain from October 23 to October 27, 2026:
As of April 10, 2026, among the 60 patients whose efficacy could be assessed, the objective response rate (ORR) was 30.0%, the disease control rate (DCR) was 80.0%, the median progression-free survival (mPFS) was 3.7 months, the median duration of remission (MdOR) was 8.7 months, and the median overall survival (MoS) was not mature. No new safety signals were observed during this follow-up.
9mW2821 is Maiwei Biologics's first new fixed-point conjugation ADC drug targeting Nectin-4. It is an innovative variety developed by the company using the ADC drug development platform. It realizes targeted antibody modification through coupling technology connectors with independent intellectual property rights and optimized ADC coupling processes. After 9MW2821 is administered, it binds to Nectin-4 on the surface of tumor cells and enters the cell. Through enzymolysis, cytotoxins are released in a targeted manner, thus achieving accurate tumor killing. 9MW2821 has now conducted multiple clinical studies on indications such as urothelial cancer (UC), cervical cancer (CC), triple-negative breast cancer (TNBC), and esophageal cancer (EC), and has enrolled more than 2,200 patients. Currently, the company is promoting four phase III key registered clinical trials, covering UC single drug and combination therapy, CC monotherapy, and TNBC (topoisomerase I inhibitor loaded ADC treatment) monotherapy. Among them, UC monotherapy and combination therapy have been included in the national breakthrough treatment category list. CC monotherapy is the world's first same-target drug to enter phase III clinical research. TNBC compatible therapy is also the first variety in the world to enter this development stage with the same indications, and has outstanding competitive advantages in the industry. The project simultaneously and rapidly carried out multiple phase I/II clinical trials. TNBC combination therapy, UC perioperative combination therapy, and EC monotherapy are in clinical phase II, EC combination therapy and CC combination therapy are in clinical phase IB/II. In terms of overseas layout, TNBC (topoisomerase I inhibitor loaded ADC treatment) monotherapy has entered clinical phase Ib in the US. According to the company's R&D plan, 9MW2821 will conduct mid-term analysis of phase III clinical trials for UC's monotherapy, combination therapy, and single drug therapy for CC in 2026, and is expected to submit a pre-marketing application meeting for the new drug to the Drug Evaluation Center of the China Drug Administration based on the mid-term analysis data.