CU-76 is an inhibitor of cyclic GMP-AMP synthase (cGAS; IC50= 0.24 uM).1It reduces DNA-, but not Sendai virus-, induced dimerization of IFN regulatory factor 3 in THP-1 cells, indicating selectivity for the cGAS DNA sensing pathway over the RIG-I-MAVS RNA sensing pathway. CU-76 decreases IFN-stimulatory DNA-induced production of IFN-beta in THP-1 cells when used at concentrations of 10, 30, and 100 uM.