BIIL-260 hydrochloride is a potent and long-acting orally active leukotriene B(4) receptor LTB₄ antagonist, with anti-inflammatory activity. BIIL-260 hydrochloride interacts with the LTB₄ receptor in a saturable, reversible, and competitive manner, has high affinity to the LTB₄ receptor on isolated human neutrophil cell membranes with K_i values of 1.7 nM^[1]. IC50 & Target: Ki: 1.7 nM (LTB₄ receptor)^[1] In Vitro: BIIL-260 hydrochloride potently inhibits LTB₄-induced intracellular Ca²⁺ release in human neutrophils with IC₅₀ value of 0.82 nM