IQ-1S is an inhibitor of NF-κB/activating protein 1 (AP-1) with an IC50 of 1.8 μM. It exhibits high binding affinity to all three JNKs, with Kd values for JNK3, JNK2, and JNK1 being 87 nM, 360 nM, and 390 nM, respectively.

JNK1:390 nM (Kd), JNK3:87 nM (Kd), PI3Kγ:1.2 μM (Kd), JNK2:360 nM (Kd), MKNK2:1.8 μM (Kd), CK1δ:1.4 μM (Kd)

IQ-1S (the sodium salt of IQ-1) is a potent, non-cytotoxic inhibitor of pro-inflammatory cytokines [IL-1α, IL-1β, IL-6, IL-10, TNF-α, interferon-γ, and GM-CSF], as well as nitric oxide produced by human and mouse monocytes/macrophages. The impact of IQ-1 on LPS-induced cytokine production in human PBMCs was evaluated. Among the 12 cytokines analyzed, LPS (200 ng/mL) consistently induced the production of five cytokines (IL-1α, IL-1β, IL-6, IL-10, and TNF-α) in PBMCs compared to DMSO-treated control cells. At a concentration of 20 μM, IQ-1 significantly inhibited the production of all these cytokines. Notably, TNF-α production was nearly completely suppressed (>99%) by IQ-1, while levels of IL-1α, IL-1β, and IL-10 were reduced by 85%, and IL-6 production decreased by 33%.

When administered via intraperitoneal injection in mice at doses of 12.5 and 30 mg/kg, IQ-1S (sodium salt of IQ-1) demonstrated adequate serum exposure, with AUC 0-12h values of 2.9 and 7.4 μM/h, respectively.