G10 is an indirect activator of stimulator of interferon genes (STING) signaling. It induces transcription of genes dependent on IRF3 and IFN, which are activated by STING, but has no effect on non-STING activated NF-κB-dependent transcription of IL-8, IL-1β, or MIP-1α in human fibroblasts. However, G10 does increase expression of NF-κB-dependent genes in human peripheral blood mononuclear cells (PBMCs) and human umbilical microvascular endothelial cells (HUMECs). In vitro, it prevents replication of the chikungunya and Venezuelan equine encephalitis alphaviruses (IC90s = 8.01 and 24.57 μM, respectively). G10 (100 μM) increases phosphorylation of IRF3, which is lost in cells lacking STING.