SUZHOU, China, May 14, 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 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.

Online Publication

Title: Updated safety and efficacy of MSB2311 (an Anti-Programmed Death-Ligand 1 Antibody) in Chinese patients with advanced solid tumors and hematological malignancies from a phase I study.

Abstract Number: e14547

First Author: Lin Shen, MD (Beijing Cancer Hospital)

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.