ES101: First Patient Dosing in Phase I Clinical Trials

June 28 , 2019 18:00

On June 28, 2019, Elpiscience Biopharmaceutical Ltd. announced first-patient dosing of first-in-class bispecific antibody ES101, targeting both PD-L1 and 4-1BB, at Shanghai East Hospital. This is the first time that the bispecific antibody drug has been administered to Chinese patients, marking the opening of a new era of tumor immunotherapy in China.


The recent progression of tumor immunotherapy has significantly benefited cancer patients. The advent of first-generation immunological checkpoint antibodies, represented by anti-PD-1/PD-L1, has brought unprecedented hope to patients, although there are still many unsolved complications. For instance, existing first-generation immune-therapies have low overall response rates. Therefore, there is a huge demand for more effective next-generation immunotherapies. Elpiscience is committed to innovate, and will promote ES101 for the first time in China.


ES101 has the potential to become the next-generation immunotherapeutic antibody. It will achieve this by executing the concept of “de-brake and add gas” for immune cell activation. De-braking is accomplished by blocking PD-1/PD-L1 checkpoint inhibitor interaction, whilst adding gas is achieved by 4-1BB-mediated immune cell engagement and activation.


Summary of ES101

ES101 is a tetravalent bispecific antibody that contains four binding domains, two targeting PD-L1 and two targeting 4-1BB, with a molecular weight being only two-thirds of that of a conventional antibody. Based on high PD-L1 expression in the tumor microenvironment and ES101’s unique antibody engineering, ES101 can conditionally activate 4-1BB upon binding to PD-L1. This would allow for more efficient and targeted tumor killing by immune cells.