Identification of mechanism-based combination targets effective with the MTA-cooperative PRMT5 inhibitor MRTX1719 for the treatment of MTAP deleted cancers (AACR 2023)
Prioritized strategies were tested in vivo where MRTX1719, in combination with agents inhibiting complementary mechanisms of action, demonstrated enhanced tumor growth inhibition compared to either agent alone, including but not limited to palbociclib (CDK4/6), olaparib (PARP), and Type I PRMT and Bcl-xL inhibitors. Further investigation into potential biomarkers conferring sensitivity or resistance to PRMT5 inhibition was also performed using orthogonal datasets including molecular characterization, differential expression, differential splicing and proteomic analysis. These data suggest MRTX1719, an MTA cooperative PRMT5 inhibitor currently in a Phase I clinical trial (NCT05245500), has the potential to be a synthetically lethal precision medicine for multiple indications harboring MTAP del with high unmet medical need either as a single agent or in combination with clinically feasible rational combination partners.