Definition

An orally bioavailable, small molecule inhibitor of cytidine triphosphate synthase 1 (CTPS1), with potential antineoplastic activity. Upon oral administration, CTPS1 inhibitor STP938 targets, binds to and inhibits the activity of CTPS1, thereby decreasing the production of cytidine triphosphate (CTP), an essential building block of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). This may disrupt DNA and RNA synthesis and trigger apoptosis. CTPS1, an enzyme that catalyzes the rate-limiting step in pyrimidine synthesis, plays an important and nonredundant role in B-cell and T-cell proliferation. CTPS1 is required for rapid cell division in certain types of cancers that arise from blood cells.