IRAK4-IN-4 is a potent dual-target inhibitor, demonstrating high activity against both cyclic GMP-AMP synthase (cGAS, IC50 = 2.1 nM) and interleukin-1 receptor-associated kinase 4 (IRAK4, IC50 = 2.8 nM). This compound is a valuable research tool for investigating innate immune signaling pathways, including the cGAS-STING and TLR/IL-1R axes, in both cellular and biochemical studies.