Skip to main content
An official website of the United States government
Government Funding Lapse
Because of a lapse in government funding, the information on this website may not be up to date, transactions submitted via the website may not be processed, and the agency may not be able to respond to inquiries until appropriations are enacted.

The NIH Clinical Center (the research hospital of NIH) is open. For more details about its operating status, please visit cc.nih.gov.

Updates regarding government operating status and resumption of normal operations can be found at opm.gov.

anti-PD-L1/4-1BB bispecific antibody ATG-101

A bispecific antibody composed of a human immunoglobulin G1 (IgG1) monoclonal antibody targeting human programmed death-ligand 1 (PD-L1) fused with a single chain variable fragment (scFv) targeting 4-1BB (CD137; tumor necrosis factor receptor superfamily member 9; TNFRSF9), with potential checkpoint inhibitory, immunostimulating and antineoplastic activities. Upon administration, anti-PD-L1/4-1BB bispecific antibody ATG-101 simultaneously targets and binds to 4-1BB, which is expressed on a variety of leukocyte subsets including activated T lymphocytes, and PD-L1 expressed on tumor cells. Upon PD-L1 binding, the 4-1BB activation signal is induced and ATG-101 acts as a conditional 4-1BB agonist in the tumor microenvironment (TME), resulting in T-cell co-stimulation and enhances T-lymphocyte-mediated anti-tumor activity. At the same time, ATG-101 prevents PD-L1 from binding to and activating its receptor, programmed cell death 1 (PD-1; PDCD1; CD279; programmed death-1). This abrogates T-cell inhibition, activates antigen-specific T lymphocytes and enhances cytotoxic T-cell-mediated tumor cell lysis, which may lead to a reduction in tumor growth. PD-L1 binding to PD-1 on activated T cells inhibits the expansion and survival of CD8-positive T cells, suppresses the immune system and results in immune evasion. 4-1BB, a surface glycoprotein of the tumor necrosis factor receptor superfamily, is an inducible costimulatory receptor that plays a key role in T-cell proliferation, survival and cytolytic activity.
Synonym:anti-PD-L1/Anti-4-1BB bispecific antibody ATG-101
anti-PD-L1/CD137 bispecific antibody ATG-101
PD-L1 x 4-1BB bispecific antibody ATG-101
Code name:ATG 101
ATG-101
ATG101
Search NCI's Drug Dictionary