#China #Shanghai #TNBC #Mabwell #9MW2821

Mabwell to Present Clinical Results for 9MW2821 at ESMO 2026

Overview

Mabwell, a leading biopharmaceutical firm in China, is set to present Phase II clinical trial results for its innovative antibody-drug conjugate (ADC), 9MW2821, at the European Society for Medical Oncology (ESMO) Congress 2026. This groundbreaking drug targets Nectin-4 and is primarily aimed at treating patients suffering from locally advanced or metastatic triple-negative breast cancer (TNBC), particularly those who have previously undergone treatment with ADCs that include a topoisomerase I inhibitor.

Trial Insights

The study, officially cataloged as CTR20242376, evaluates the safety and efficacy of 9MW2821 as either a stand-alone treatment or in combination with a PD-1 monoclonal antibody in patients categorized as ADC-pretreated for TNBC. As of April 10, 2026, results from 60 patients eligible for efficacy evaluation have shown promising outcomes:

• - Objective Response Rate (ORR): 30.0%
• - Disease Control Rate (DCR): 80.0%
• - Median Progression-Free Survival (mPFS): 3.7 months
• - Median Duration of Response (mDOR): 8.7 months
• - Median Overall Survival (mOS): Data is yet to mature.

The interim findings suggest that 9MW2821 not only demonstrates a manageable safety profile but also offers significant therapeutic benefits for TNBC patients, a demographic facing a pressing need for new treatment options.

Context of TNBC

Breast cancer poses a significant health challenge, particularly in China, where recent statistics reveal an estimated 375,800 new cases in 2024, leading to approximately 73,000 fatalities. TNBC, which comprises 15% to 20% of all breast cancer cases, is notorious for its aggressive nature and poor prognosis. Current treatment protocols reliance primarily on topoisomerase I inhibitor-containing ADCs. For patients who do not respond to these initial treatments, further chemotherapy options remain inadequate, underscoring an urgent demand for innovative therapies such as 9MW2821.

About 9MW2821

9MW2821 was developed through Mabwell's proprietary ADC platform aimed at Nectin-4. The drug is currently undergoing multiple clinical trials for various indications, including urothelial carcinoma (UC), cervical cancer (CC), and esophageal cancer (EC), with a combined enrollment of over 2,200 patients. Notably, the drug has received Breakthrough Therapy Designation from China’s Center for Drug Evaluation (CDE) for UC treatments, both as monotherapy and in conjunction with other therapies. Moreover, it stands out as the first Nectin-4 targeting agent in Phase III trials for CC and also holds the distinction of being the first ADC targeting TNBC patients pretreated with topoisomerase I inhibitors to reach Phase III status.

Future Directions

Looking ahead, interim analyses for the Phase III trials focused on UC and CC are scheduled for 2026, with the prospect of submitting pre-NDA meeting applications to the CDE following the results. Concurrently, clinical trials for TNBC are advancing quickly, including ongoing Phase Ib trials in the United States.

Company Background

Mabwell is an innovative biopharmaceutical company dedicated to advancing global healthcare solutions, with a special emphasis on oncology and aging-related conditions. The firm espouses a mission to improve health outcomes in society while maintaining a clear vision of transforming ideas into tangible health solutions. To learn more, interested parties can visit Mabwell's website.

Mabwell's research and innovation in ADC technology signify a pivotal step forward in addressing the medical needs of patients suffering from aggressive cancers like TNBC. By exploring uncharted territories in cancer therapy, the company aims to deliver substantial advancements in treatment options and patient care.