The board of directors of Transcenta Holding Limited announced a collaboration with Agilent Technologies to develop a Claudin18.2(CLDN18.2) companion diagnostic to support TranStar301 global Phase III pivotal trial of Osemitamab (TST001) in combination with Nivolumab and chemotherapy as first-line treatment in patients with CLDN18.2 expressing locally advanced or metastatic gastric or gastroesophageal (G/GEJ) adenocarcinoma. The Company has developed a mouse anti-CLDN18.2 monoclonal antibody, clone 14G11 which specifically binds to CLDN18.2 but not CLDN18.1. This antibody, generated against a linear epitope located on the extracellular domain of loop1, has a binding site that overlaps with the binding site of therapeutic antibody Osemitamab (TST001). The Company has been collaborating with Agilent, a world leader in CDx development, to further develop this antibody for use in a companion diagnostic assay.

Agilent is developing CLDN18.2 IHC 14G11 pharmDx, an immunohistochemistry (IHC) assay for the detection of CLDN18.2 protein in gastric and gastroesophageal junction (GEJ) adenocARCinoma with the potential for other indications. Agilent and the Company presented the early results of the CLDN18.2 I HC 14G11 pharmDx assay at AACR Annual Meeting. CLDN18.2 IMC 14G11 pharmDx for Investigational Use Only/for Performance Evaluation Only will be used for patient selection in the phase III trial of gastric/gastroesophageal GEJ adenocarcinoma where applicable ethics committee and regulatory approvals have been granted.

Osemitamab (tST001) is a high affinity humanized anti-CLDN18. 2 monoclonal antibody with enhanced antibody-dependent cellular cytotoxicity ("ADCC"). It has shown potent anti-tumor activities in tumor xenograft models.

Osemitamab is the second most advanced CLDN18.2 targeting antibody being developed globally. Osemitamab ("TST001") was generated using the Company's Immune Tolerance Breaking Technology (IMTB) platform. Osemitamab(TST001) kills CLDN18.2 expressing tumor cells by mechanisms of ADCC.

Leveraging advanced bioprocessing technology, the fucose content of Osemitamab (" TST001) was significantly reduced during the production, which further enhanced NK cells mediated ADCC activity of Osemitamab. Clinical trials for Osemitamab (tST001) are ongoing in China and the U.S. (NCT05190575, NCT04396821, NCT04495296, NCT05608785/CTR20201281). Osemitamab (TST001) has been granted Orphan Drug Designation in the U.S. by FDA for the treatment of patients with gastric or gastroesophageal junction (G/GEJ) and pancreatic cancer.