Mabwell Announces 9MW2821 Clinical Data and Latest Progress to be presented at 2024 ASCO Annual Meeting

SHANGHAI,May 24,2024 -- Mabwell (688062.SH),an innovation-driven biopharmaceutical company,announced the data and latest progress of the Phase I/II clinical study of 9MW2821,a novel Nectin-4-targeting ADC for multiple advanced solid tumors,which will be reported as an oral presentation at the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting.

As of April 1,2024,among 240 patients in the 1.25 mg/kg dose group in the Phase II clinical trial:

>> Urothelial Carcinoma (UC)

Of the 37 patients evaluable for efficacy assessment,the objective response rate (ORR) and disease control rate (DCR) were 62.2% and 91.9%,respectively,with median progression-free survival (mPFS) was 8.8 months and median overall survival (mOS) was 14.2 months.

>> Cervical Cancer (CC)

Of the 53 patients evaluable for efficacy assessment,51% were previouslytreated with platinum-baseddoubletchemotherapyand bevacizumab,and 58% received platinum-baseddoubletchemotherapy and immune checkpoint inhibitor,with ORR and DCR were 35.8% and 81.1%,respectively. The mPFS was 3.9 months,with mOS not reached. Of the patients with Nectin-4 tumor cell staining intensity 3+,the ORR was 43.6% among the 39 evaluable patients.

>> Esophageal Cancer (EC)

Of the 39 patients evaluable for efficacy assessment,ORR and DCR were 23.1% and 69.2%,with mPFS of 3.9 months and mOS of 8.2 months; 37 of them were treated with platinum-based chemotherapy and immunotherapy previously.

>> Triple-negative Breast Cancer (TNBC)

Of the 20 patients with locally advanced or metastatic triple-negative breast cancer and evaluable for efficacy assessment,the ORR and DCR were 50.0% and 80.0% respectively. The mPFS was 5.9 months,and the mOS was not yet reached,with one patient achieved complete response (CR) and had been in CR for 20 months and is currently sustained to be CR.

>> Safety Profile

To date,the most common treatment-related adverse events (all grade,≥grade 3) in the 240 patients in the 1.25 mg/kg dose group were white blood cell count decreased (50.8%,23.3%),neutrophil count decreased (46.3%,27.9%),anemia (43.8%,8.3%),aspartate aminotransferase increased (42.1%,2.9%),alanine aminotransferase increased (35.4%,2.1%),asthenia (32.1%,rash (30.0%,5.0%),decreased appetite (28.8%,1.3%),nausea (26.7%,0%),hyperglycemia (25.4%,platelet count decreased (24.2%,4.6%),alopecia (24.2%,hypoaesthesia (22.5%,1.7%),constipation (21.3%,vomiting (20.9%,hypertriglyceridemia (20.4%,and gamma glutamyl aminotransferase increased (15.8%,5.4%). The data suggest that 9MW2821 has a manageable safety profile.

About 9MW2821

9MW2821 is the first site-specific conjugated novel Nectin-4-targetingADCdeveloped by Mabwell using ADC platform and automated high-throughput hybridoma antibody molecular discovery platform,and is the first drug candidate to enter clinical study among the Nectin-4-targeting ADCs developed by Chinese companies,and the first therapeutic drug candidate targeting Nectin-4 in the world to reveal clinical efficacy data of cervical cancer,esophageal cancer and breast cancer. 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 in Feb. 2024 and May 2024,respectively.

9MW2821 achieves site-specific modification of antibody through proprietary conjugate technology linkers and optimized ADC conjugation process. After injection,9MW2821 can specifically bind to Nectin-4 on the cell membrane surface,be internalized and release cytotoxic drug,and induce the apoptosis of tumor cells.

About Mabwell

Mabwell (688062.SH) is an innovation-driven biopharmaceutical company with the entire value chain of the pharmaceutical industry. We provide more effective and accessible therapy and innovative medicines to fulfill global medical needs. Since 2017,an advanced R&D system which covers target discovery,early discovery,druggability,preclinical,clinical research and manufacturing transformation was established. Mabwell has 14 pipeline products in different stages based on a world-class and state-of-the-art R&D engine,including 10 novel drug candidates and 4 biosimilars. We focus on the therapeutic areas of oncology,auto-immune diseases,metabolic disorders,ophthalmologic diseases and infectious diseases,etc. Of these,3 products have been approved and commercialized,1 product has been filed for MA approval,3 products are in pivotal trials. We have also undertaken 1 national major scientific and technological special project for "Significant New Drugs Development",2 projects for National Key R&D Programmes,and multiple provincial and municipal science and technological innovation projects. Mabwell's Taizhou factory possesses robust in-house manufacturing capability compliant with international GMP standards regulated by the NMPA,FDA and EMA,and has passed the EU QP Audit. The large-scale manufacturing base located in Shanghai is under construction. Our mission is "Explore Life,Benefit Health" and our vision is "Innovation,from ideas to reality". For more information,please visit www.mabwell.com/en.

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