BioNTech and DualityBio Announce Topline Results of the DYNASTY-Breast02 Global Phase 3 Clinical Trial Evaluating Trastuzumab Pamirtecan in HR+/HER2-low Metastatic Breast Cancer

MAINZ, Germany and SHANGHAI, China, October 26, 2026 – BioNTech SE (Nasdaq: BNTX, “BioNTech”) and DualityBiologics (Suzhou) Co., Ltd. (“DualityBio”, HKEX: 9606.HK) announced today that the DYNASTY-Breast02 global Phase 3 clinical trial ( NCT06018337 ) met its primary endpoint demonstrating a statistically significant, yet modest improvement in progression-free survival (“PFS”) with trastuzumab pamirtecan (BNT323/DB-1303) compared to investigator’s choice of chemotherapy in chemotherapy-naïve patients with HR+/HER2-low metastatic breast cancer who have progressed on endocrine therapy. At this interim analysis for the secondary endpoint of overall survival (“OS”), data were not mature.