SB 203580

A potent and selective inhibitor of p38 MAP kinase, IC50=50 and 500 nM for p38 and p38β2 respectively. No other kinases (in a panel of 30) were significantly inhibited including p38γ and δ at 10 μM2. A potent inhibitor of inflammatory cytokine production (IC50=15-25 mg/kg in mice and rats) in animal models of arthritis, bone resorption, endotoxin shock and immune function3.