molecules of the month

MRTX1719 is PRMT5-MTA complex inhibitor for the treatment of MTAP-deleted cancers currently in IND-enabling studies. PRMT5 is a target of active interest with several molecules recently highlighted here. Inhibition of PRMT5 is expected to induce synthetic lethality in MTAP-deleted tumors – however, PRMT5 is also an essential gene for hematopoesis, and therefore most PRMT5 inhibitors also lead to dose-limiting cytopenias. MRTX1719, in contrast, inhibits PRMT5 cooperatively with MTA (methylthioadenosine), which is accumulated in MTAP-deleted cells. This mechanism of action may allow greater differentiation between MTAP-deleted tumor cells and healthy hematopoetic stem cells. The molecule is orally active in a preclinical model with once daily dosing. The molecule emerged from a fragment-based drug discovery campaign specifically focused on the PRMT5-MTA complex,…