ETH615 (4-[2-quinolylmethoxy]-N-[3-fluorobenzyl]-phenylaminometh yl-4-benzoic acid) is a potent inhibitor of leukotriene biosynthesis in A23187-stimulated leukocytes, and of IL-8 gene expression in LPS-stimulated PBMC. It shows anti-inflammatory activity in a canine model of dermal inflammation. A topical formulation is present in phase II clinical trials. In the present study the effect of ETH615 on oxazolone-induced acute inflammation and phorbol ester-induced chronic inflammation in the mouse ear was investigated. Betamethasone (0.04 mg/ear) and ETH615 (1-1.5 mg/ear) significantly inhibited both the oedema formation and the PMN infiltration. The cream and ointment formulations of ETH615 developed for clinical studies were equally active. ETH615 is thus an anti-inflammatory agent in these murine models of dermatosis.