Sino Biopharmaceutical Ltd (HKG: 01177) has announced that its independently developed Class 1 innovative drug, TQB2102 injection, a HER2 bispecific antibody-drug conjugate (ADC), has received acceptance for a New Drug Application (NDA) submission from China’s National Medical Products Administration (NMPA) via its Center for Drug Evaluation (CDE). This filing targets adult patients with unresectable or metastatic HER2-low expressing breast cancer—defined as IHC 1+ or IHC 2+/ISH-—who have not previously undergone chemotherapy for recurrent or metastatic disease. The CDE had earlier granted Breakthrough Therapy designation for this indication, underscoring the drug’s potential significance.

TQB2102 stands out as the world’s first HER2 bispecific ADC to achieve positive Phase III results in HER2-low breast cancer. The pivotal TQB2102-Ⅲ-01 study, a randomized, open-label, active-controlled, multicenter trial, enrolled 543 patients with HER2-low breast cancer. Per an evaluation by an independent Data Monitoring Committee (IDMC), the interim analysis met both the pre-specified primary and key secondary endpoints. Compared to the investigator’s chosen chemotherapy, TQB2102 demonstrated a statistically robust and clinically meaningful improvement in progression-free survival (PFS), significantly reducing the risk of disease progression or death. Detailed findings from this trial will be presented at a future international academic conference.

The drug’s design incorporates an asymmetric antibody structure that binds to two distinct domains—ECD II and ECD IV—of the HER2 receptor, leveraging bispecific epitope synergy to boost tumor cell binding and internalization efficiency. A cleavable linker system enables a potent bystander effect, expanding the cytotoxic impact on heterogeneous tumors. With a drug-to-antibody ratio (DAR) optimized to approximately 5.8-6.0, TQB2102 carries a Topoisomerase I (Topo I) inhibitor payload, balancing enhanced antitumor activity with a favorable safety profile. This novel engineering overcomes the limitations of traditional HER2 monoclonal antibodies or monospecific ADCs, offering distinct advantages in treating HER2-low tumors.

Currently, TQB2102 is being evaluated in multiple Phase III trials across diverse HER2 expression levels and tumor types, including HER2-low breast cancer, neoadjuvant therapy for HER2-positive breast cancer, first-line and later-line treatments for HER2-positive advanced breast cancer, and later-line therapy for HER2-positive biliary tract and colorectal cancers. Notably, three of these indications have secured Breakthrough Therapy designations from the CDE, highlighting the asset’s broad potential in HER2-expressing solid tumors. In a strategic move, the group previously inked an exclusive licensing and supply agreement with Cipla Limited, granting Cipla rights to develop and commercialize TQB2102 in India, South Africa, and five other emerging markets, while the group continues to handle production and supply. To date, TQB2102 has secured two regional licensing partnerships, generating cumulative upfront and milestone payments of approximately $30 million, reflecting the asset’s commercial value and the group’s robust regional collaboration framework.