BC-1215 is an inhibitor of F-box protein 3 (FBXO3, a ubiquitin E3 ligase component, IC50=0.9 μg/mL for IL-1β release). BC-1215 decreases Fbxo3-Fbxl2 interaction and prevents SCFFbxo3 catalyzed Fbxl2 ubiquitination. BC-1215 inhibits the Fbxo3-TRAF activation pathway by destabilizing TRAF1–TRAF6. BC-1215, interacts with ApaG to profoundly inhibit secretion of a broad spectrum of TH1 panel cytokines from human PBMC.