EQ504

EQ504 is a potent and selective modulator of the aryl hydrocarbon receptor (AhR), developed by Equillium. It features a unique, multi-modal, non-immunosuppressive mechanism of action that distinguishes it from conventional immunosuppressants. EQ504 selectively enhances regulatory T cells (Tregs) while suppressing pathogenic Th17 cells, thereby rebalancing immune responses in barrier tissues such as the gut and skin. The drug promotes healing of intestinal epithelial cells by inducing anti-inflammatory cytokines like IL-22RA and IL-10, preserves barrier function, and supports tissue repair and regeneration. Preclinical studies have demonstrated its efficacy in protecting against gut damage in models of ulcerative colitis, with potential for targeted local delivery via enteric coating or inhaled formulations for gastrointestinal or inflammatory lung diseases[1][2][3][5][6][8].