Transcenta Announces Updated Clinical Data from Phase I Study of pH-Dependent PD-L1 Antibody MSB2311 to Be Presented at the 2021 ASCO Annual Meeting

Transcenta Holding Limited, a clinical stage global biotherapeutics company with fully-integrated capabilities in discovery, development and manufacturing of antibody-based therapeutics, today announced that the updated phase I clinical data on the safety and efficacy of MSB2311, a pH-dependent PD-L1 antibody, in Chinese patients with advanced solid tumors and hematological malignancies will be presented as an abstract online publication at the 57th American Society of Clinical Oncology (ASCO) Annual Meeting. The 2021 ASCO Annual Meeting will be held online from June 4th to June 8th EDT.

About MSB2311

MSB2311 is an investigational humanized PD-L1 antibody with pH dependent binding property. PD-L1 is involved in inhibiting the immune system's response to fight cancer. MSB2311 blocks the interaction between PD-L1 and PD-1, which reactivates the suppressed or exhausted anti-tumor effector T cell function in the tumor microenvironment. MSB2311 employs engineered IgG1 which lacks FcR binding. In addition, the binding of MSB2311 to PD-L1 results in internalization of MSB2311 and MSB2311 can dissociate from bound PD-L1 in endosome with pH level lower than 5.5. This allows MSB2311 to be recycled to plasma membrane and be reused to bind with PD-L1 on another tumor cell or immune cell. Results from preclinical studies demonstrate that MSB2311 can inhibit tumor growth of PD-L1 expressing tumor cells in syngeneic mouse-model. Two phase 1 studies of MSB2311 have been completed in the US and China. MSB2311 is currently to be tested in phase 2 trial in patients with solid tumors expressing select biomarker in China.

About Transcenta Holding Limited.

Transcenta is a clinical stage global biotherapeutics company that fully integrates antibody-based biotherapeutics discovery, development and manufacturing. Transcenta has established global footprint, with Headquarter and Discovery and Translational Research Center in Suzhou, Process and Product Development Center and Manufacturing Facility in Hangzhou, and Clinical Development Centers in Beijing, Shanghai and Guangzhou in China and in Princeton, US, and External Partnering Center in Boston, US. Transcenta is developing a panel of nine antibody molecules for oncology and selected non-oncology indications including bone and kidney disorders. Upon the latest financing, the company has raised over $342 million from globally prominent investors.