Yingen Bio-B (09606): The Dynasty-Breast02 global phase 3 clinical trial (NCT06018337) has reached its main research end

Zhitong Finance App News, Yingen Bio-B (09606) announced that the Dynasty-Breast02 global phase 3 clinical trial (NCT06018337) has reached its main research end. The study results showed that among patients with HR+/HER2-low metastatic breast cancer who had progressed after receiving endocrine treatment and had not received chemotherapy, compared with the chemotherapy control group selected by the researchers, pacontrazumab (DB-1303/BNT323) (an investigational antibody drug conjugate targeting HER2 ( ADC)) achieved a statistically significant modest improvement in progression-free survival (PFS). As of this mid-term analysis, data on overall survival (OS) for secondary endpoints is not mature.

The overall incidence of interstitial lung disease (ILD) reported in this study was higher than previous clinical trials with pacontrastuzumab, and the vast majority of events were grade 1 or 2. A small number of patients reported grade 3-5 events. In addition, the overall safety characteristics of this study were basically consistent with previous clinical trials, and no new safety signals were observed.

The efficacy and safety data obtained as of the current data cut-off date suggest that, combined with the current treatment pattern for HR+/ HER2 low expression metastatic breast cancer, the potential clinical benefit space for this specific patient population may be relatively limited. The company and BioNTech SE (BioNTech, the company's partner for pacantrazumab) will further analyze and discuss the data and evaluate follow-up arrangements.

The company and BioNTech are developing pacontrazumab in three ongoing clinical trials, including two global phase 3 clinical trials, one for HR+/ HER2 low expression metastatic breast cancer (NCT06018337), the other for recurrent endometrial cancer with HER2 expression (NCT06340568); and a global phase 1/2 clinical trial (NCT05150691) for patients with advanced metastatic solid tumours.