CRX-526 is a TLR4 antagonist that can block the interaction of lipopolysaccharide (LPS,) with the immune system, including preventing the expression of pro-inflammatory genes stimulated by LPS, as well as blocking the release of TNF-α induced by LPS. CRX-526 exhibits anti-inflammatory effects in two mouse models of colitis (namely, the dextran sodium sulfate-induced colitis model and the multidrug resistance gene 1a-deficient mouse model).