December 10th, 2025, Shanghai, China – DualityBio (Stock Code: 9606.HK) presented preliminary data from an ongoing Phase 1/2 clinical trial (NCT05914116) evaluating DB-1311/BNT324, a next-generation antibody-drug conjugate (ADC) candidate targeting B7H3, developed in collaboration with BioNTech, in patients with advanced solid tumors. The analysis included patients with heavily pre-treated cervical cancer (“CC”) and platinum-resistant ovarian cancer (“PROC”) and showed a manageable safety profile and early signs of antitumor activity. The data have been presented as an oral presentation at the European Society for Molecular Oncology (“ESMO”) ASIA Congress 2025 in Singapore.

The trial evaluated DB-1311/BNT324 in patients with previously treated advanced solid tumors. The primary endpoint of the trial was the safety (Phase 1 and Phase 2a) and objective response rate (ORR) (Phase 2a). Secondary endpoints included duration of response (DoR), disease control rate (DCR), progression free survival (PFS), and overall survival (OS).

The analysis at the September 5, 2025, data cut-off included 30 patients with CC (Cohort 7), and 12 patients with PROC (Cohort 8), who received DB-1311/BNT324 as monotherapy. The safety profile of the candidate was consistent with previous reports and overall manageable. Nausea and hematological events, mainly Grade 1-2, were the most common treatment-related adverse events (TRAEs). No TRAEs led to death.  Among the 30 efficacy-evaluable patients with advanced CC, the confirmed objective response rate (cORR) was 33.3%, the disease control rate (DCR) was 86.7%, and the median progression-free survival (PFS)  was 7.0 months. Meanwhile, among the 12 efficacy-evaluable patients in PROC, the cORR was 58.3%, the DCR was 75.0%, and the median PFS was 8.2 months, confirming its broad therapeutic potential in gynecological cancers.

Currently, a dose-expansion cohort to optimize the DB-1311/BNT324 monotherapy regimen in PROC is ongoing. In addition, a Phase 2 clinical trial (NCT06953089), sponsored by DualityBio, is evaluating DB-1311/BNT324 in combination with an investigational PD-L1xVEGF-A bispecific antibody to explore the combination potential of these treatment approaches across several tumor types, including CC and PROC.

About DualityBio

Duality Biotherapeutics (HKEX:09606) is a clinical-stage biotech company dedicated to the discovery and development of next-generation ADCs to treat cancer and autoimmune diseases. DualityBio has successfully built several cutting-edge ADC technology platforms with global intellectual property rights. Leveraging a robust pipeline, DualityBio is conducting multiple global clinical trials across 20 countries and has enrolled over 2,700 patients for multiple clinical-stage ADC candidates.

Additionally, DualityBio has established strategic collaborations with global MNCs and leading biotech innovators. As a global ADC powerhouse, DualityBio is developing novel ADCs, including bispecific ADC candidates, novel-payload ADC candidates, and autoimmune ADC candidates.

For more information, please visit: www.dualitybiologics.com.

About DB-1311/BNT324

DB-1311/BNT324 is a next-generation topoisomerase-I-inhibitor-based ADC candidate targeting the immune checkpoint protein B7-H3. The transmembrane glycoprotein B7-H3 plays a critical role in the anti-tumor immune response and the shaping of the tumor microenvironment. It is overexpressed in a range of solid tumors, with limited expression in healthy tissues, and has been associated with disease progression and very poor prognosis. Preclinical studies have shown that  DB-1311/BNT324 exhibits antitumor activity in various solid tumor models. Preliminary data from the ongoing Phase 1/2 trial has demonstrated antitumor activity and a manageable safety profile for  DB-1311/BNT324 in patients with advanced solid tumors.  DB-1311/BNT324 is currently being evaluated as a monotherapy in a Phase 1/2 clinical trial (NCT05914116) in patients with advanced or metastatic solid tumors, and in combination with an investigational anti-PD-L1xVEGF-A antibody in a Phase 2 clinical trial (NCT06953089) in patients with advanced or metastatic solid tumors and an Phase 1/2 clinical trial (NCT06892548) in patients with advanced lung cancers.

Media Contact: PR@dualitybiologics.com

Investor Contact: IR@dualitybiologics.com