SUZHOU, China, April 19, 2021 -- Transcenta Holding Limited (Transcenta), a clinical stage global biotherapeutics company with fully-integrated capabilities in discovery, development and manufacturing of antibody-based therapeutics, today announced the first patient has been successfully dosed in Phase I clinical study of TST001, a humanized monoclonal antibody targeting human Claudin18.2 (CLDN18.2), in combination with CAPOX for the treatment of patients with first-line locally advanced unresectable or metastatic gastric cancer.

TST001 is a second-generation recombinant humanized monoclonal antibody targeted CLDN18.2，generated by Transcenta's independently-developed Immune Tolerance Breaking Technology (IMTB) platform. TST001 can target and kill tumor cells expressing CLDN18.2 by leveraging mechanisms such as complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC) through combining CLDN18.2 with high specificity and affinity. With advanced technology, the fucose content of TST001 was significantly reduced during the production, which further enhanced the ADCC-mediated tumor killing activity of TST001. TST001 displayed more potent anti-tumor activities than IMAB362 analog in mouse xenograft experiments. Clinical trials for TST001 have been launched in China and US since July 2020 (NCT04396821, NCT04495296/CTR20201281).

"CLDN18.2 is found to be overexpressed in many tumors including gastric cancer，pancreatic cancer and esophageal cancer. At present, the first-in-class drug IMAB362 has shown promising efficacy in phase II FAST study mainly in first-line gastric cancer patients with high CLDN18.2 expression. "Professor Lin Shen from Beijing Cancer Hospital, believes that "Rapidly advancing the study of the combination of TST001 and standard chemotherapy in first-line gastric cancer patients could help us to accelerate the assessment of its therapeutic value in large number of gastric cancer patients expressing CLDN18.2."

"Gastric cancer is the most common tumor species in China and Asia. About 70% of gastric cancer patients express CLDN18.2. TST001 is a second-generation recombinant humanized monoclonal antibody targeted CLDN18.2. Preclinical studies have found that TST001 can not only efficiently kill gastric cancer cells with high expression of CLDN18.2, but also be very effective against gastric cancer cells with moderate to high expression of CLDN18.2. TST001 has been launched in clinical research in China and US in July 2020. We hope to explore the safety, tolerability and anti-tumor activity of TST001 combined with CAPOX in first-line gastric cancer patients through this study, so as to provide a basis for later registrational clinical studies." said Dr. Michael Shi, EVP, Head of Global R&D and CMO of Transcenta.