TLR9 antagonist 1 diformate is a selective hTLR9 antagonist with an IC50 of 0.1 nM against hTLR9. TLR9 antagonist 1 diformate exhibits favorable pharmacokinetic and pharmacodynamic properties. TLR9 antagonist 1 diformate can be used in the research of systemic lupus erythematosus [1].
In Vivo, TLR9 antagonist 1 (1-10 mg/kg; i.p.; single dose) diformate significantly reduces the levels of proinflammatory cytokines induced by TLR9 agonists in C57BL/6J mice[1].
In Vitro, TLR9 antagonist 1 (compound 38) diformate inhibits TLR9 activity in human peripheral blood mononuclear cells with an IC50 of 4 nM[1]. TLR9 antagonist 1 diformate exerts no significant inhibitory effect on human TLR2, TLR4 or TLR5, and exhibits a selectivity of >10000-fold for these receptors over human TLR9[1].
References:
[1]. Song X, et al. Discovery of Potent and Selective Quinoline-Based Toll-like Receptor 9 Antagonists. ACS Med Chem Lett. 2025 Aug 26;16(9):1747-1755.
In Vivo, TLR9 antagonist 1 (1-10 mg/kg; i.p.; single dose) diformate significantly reduces the levels of proinflammatory cytokines induced by TLR9 agonists in C57BL/6J mice[1].
In Vitro, TLR9 antagonist 1 (compound 38) diformate inhibits TLR9 activity in human peripheral blood mononuclear cells with an IC50 of 4 nM[1]. TLR9 antagonist 1 diformate exerts no significant inhibitory effect on human TLR2, TLR4 or TLR5, and exhibits a selectivity of >10000-fold for these receptors over human TLR9[1].
References:
[1]. Song X, et al. Discovery of Potent and Selective Quinoline-Based Toll-like Receptor 9 Antagonists. ACS Med Chem Lett. 2025 Aug 26;16(9):1747-1755.
















