Bay 65-1942 free base is primarily utilized in research settings as a potent and selective inhibitor of the enzyme TBK1 (TANK-binding kinase 1). Its application is significant in studying signaling pathways related to immunity, inflammation, and cancer. Researchers use it to explore the role of TBK1 in cellular processes such as interferon production, autophagy, and cell survival. By inhibiting TBK1, it helps in understanding its function in diseases like rheumatoid arthritis, lupus, and certain cancers. Additionally, it serves as a valuable tool in drug discovery efforts aimed at developing therapeutic agents targeting TBK1-mediated pathways.