NS6180 is a novel potent and selective KCa3.1 channel inhibitor(IC50= 9 nM) prevents T-cell activation and inflammation. IC50 value: 9 nM [1] Target: KCa3.1 channel inhibitor in vitro: NS6180 inhibited cloned human KCa3.1 channels (IC50 = 9 nM) via T250 and V275, the same amino acid residues conferring sensitivity to triarylmethanes such as like TRAM-34. NS6180 inhibited endogenously expressed KCa3.1 channels in human, mouse and rat erythrocytes, with similar potencies (15–20 nM). NS6180 suppressed rat and mouse splenocyte proliferation at submicrolar concentrations and potently inhibited IL-2 and IFN-γ production, while exerting smaller effects on IL-4 and TNF-α and no effect on IL-17 production [1]. in vivo: DNBS challenged rats were treated with two doses (3 and 10 mg·kg-1 b.i.d.) of NS6180 for 7 days in direct comparison with the IBD drug sulfasalazine (300 mg·kg-1 q.d.). Both doses of NS6180 significantly improved weight gain and decreased inflammation induced swelling of the colon as determined by relative colon weight.