The board of directors of Transcenta Holding Limited announced that the enrollment of first-line (1L) CLDN18.2 expressing Gastric/Gastro-esophageal Junction (G/GEJ) adenocarcinoma patients in cohorts C and G for the China Phase II study (Transtar-102, NCT04495296) of its high affinity humanized ADCC-enhanced anti-CLDN18.2 monoclonal antibody Osemitamab (TST001) has been completed. Cohort G evaluates Osemitamab in combination with Nivolumab plus Capecitabine and Oxaliplatin (CAPOX). These clinical data lay the foundation of its Phase III and comply with dose optimization requirements from Health Authorities.

They also provide important information related to the predictive role of CLDN18.2 expression on Osemitamab (TST001) associated outcomes, particularly in the medium and low expressors. Osemitamab is a high affinity humanized anti-CLDN18. 2 monoclonal antibody with enhanced antibody-dependent cellular cytotoxicity ("ADCC") and complement-dependent cytotoxicity ("CDC") activities and potent anti-tumor activities in tumor xenograft models.

Osemitamab (tST001) is the second most advanced CLDN18.2 targeting antibody being developed globally. Osemitamab ("TST001") is generated using the Company's Immune Tolerance Breaking Technology (IMTB) platform. Osemitamab(TST001) kills CLDN18.2 expressing tumor cells by mechanisms of ADCC and CDC.

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 (MST001) are ongoing in the U.S. and China (NCT05190575, NCT04396821, NCT04495296, NCT05608785/CTR20201281). Osemitamab (S. and China (N CT05190575,NCT04396821, NCT05608785/CTR20201281).

O Semitamab (TST01) was 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.