AZD-9574 is a potent and brain penetrant PARP1 inhibitor and shows >8000-fold selectivity for PARP1 compared to PARP2/3/5a/6. AZD-9574 acts by selectively inhibiting and trapping PARP1 at the sites of SSBs. AZD-9574 is an anti-cancer agent and can be used for HRD + breast cancer and advanced solid malignancies research.