Challenge studies of a leukotriene receptor antagonist

The leukotriene receptor antagonist pranlukast (SB 205312, ONO-1078) has demonstrated clinical activity as an antiasthma drug in traditional challenge models, including exercise-induced asthma and inhaled bronchoprovocations with sulpyrine (an aspirin analogue), antigen, methacholine, leukotriene C4, and leukotriene D4. This article reviews the results of a published sulpyrine-challenge study and two unpublished house dust mite antigen challenge studies. Statistically significant attenuation of the decrease in FEV1 induced by bronchoprovocation was observed with pranlukast compared with placebo or baseline control in all challenge studies. These challenge studies demonstrate that pranlukast significantly protects against aspirin-induced bronchoconstriction and significantly attenuates both the immediate (early) and late airway responses to inhaled allergen.