TNG908 is a brain-penetrant, MTA-cooperative PRMT5 inhibitor developed for the treatment of MTAP-deleted cancers
Kimberly J. Briggs, Kevin M. Cottrell, Matthew R. Tonini, Alice Tsai, Minjie Zhang, Douglas A. Whittington, Wenhai Zhang, Steven A. Lombardo, Satoshi Yoda, Erik Wilker, Samuel R. Meier, Yi Yu, Teng Teng, Alan Huang, John P. Maxwell
Abstract
TNG908 is a clinical stage PRMT5 inhibitor with an MTA-cooperative binding mechanism designed to leverage the synthetic lethal interaction between PRMT5 inhibition and MTAP deletion. MTAP deletion occurs in 10–15 % of all human cancer representing multiple histologies. MTA is a negative regulator of PRMT5 that accumulates as a result of MTAP deletion. In this study, we demonstrate that TNG908 selectively binds the PRMT5·MTA complex driving selective inhibition of PRMT5 in MTAP-null cancers, a mechanism that creates a large therapeutic index relative to first generation PRMT5 inhibitors that have alternative binding mechanisms that are not tumor-selective. Strong preclinical activity in multiple MTAP -deleted xenograft models, as well as demonstrated brain penetrance in preclinical models, support the potential for histology-agnostic clinical development of TNG908 in MTAP -deleted solid tumors, including CNS malignancies. TNG908 is being tested clinically in patients with MTAP -deleted tumors, including glioblastoma, in a Phase I/II clinical trial (NCT05275478). • TNG908 is a clinical-stage, brain-penetrant, MTA-cooperative PRMT5 inhibitor developed for the treatment of MTAP -deleted solid tumors • TNG908 is 15X selective for MTAP -deleted cancer cells relative to MTAP-proficient cells • TNG908 drives strong antitumor activity, including sustained tumor regressions, in MTAP -deleted xenograft models representing multiple tumor histologies including glioblastoma. • Novel combination partners for MTA-cooperative PRMT5 inhibitors identified by rational and functional genomics-based approaches include MAT2A and CDK4/6 inhibitors. • TNG908 is being tested clinically in a phase I/II trial in MTAP -deleted solid tumors including glioblastoma (NCT05275478).