BRIEF—FDA Breakthrough status for BioNTech and Duality's BNT323/DB-1303 in endometrial cancer

The US Food and Drug Administration (FDA) has granted Breakthrough Therapy designation for BNT323/DB-1303 for the treatment of advanced endometrial cancer in patients who progressed on or after treatment with immune checkpoint inhibitors.

Under development by Germany’s BioNTech and China-based Duality Biologic, BNT323/DB-1303 is a next-generation antibody-drug conjugate (ADC) candidate targeting the human epidermal growth factor receptor 2 (HER2), a cell surface protein which is expressed in a range of tumor types.

The designation is based on encouraging top-line data from a Phase I/II study with BNT323/DB-1303 in patients with HER2-expressing advanced endometrial cancer.

Data from the ongoing Phase I/II study demonstrated encouraging anti-tumor activity in heavily pre-treated patients with advanced endometrial cancer with an unconfirmed objective response rate of 58.8% and an unconfirmed disease control rate of 94.1%. BNT323/DB-1303 was well tolerated with a manageable safety profile across all evaluated patients with advanced/metastatic solid tumors.