Can a single dose response predict the effect of montelukast on exercise‐induced bronchoconstriction?

Summary Rationale Exercise‐induced bronchoconstriction (EIB) can be prevented by a single dose of montelukast (MLK). The effect is variable, similar to the variable responsiveness observed after daily treatment with MLK. We hypothesized that the effect of a single MLK‐dose (5 or 10 mg) on EIB could predict the clinical effectiveness of longer term once daily treatment. Methods This was a prospective, open‐label study. Twenty‐four asthmatic adolescents (12–17 years) suboptimally controlled by low‐dose inhaled corticosteroids, with ≥10% post‐exercise fall in FEV 1 , were included. They performed an exercise test at baseline, 20 hr after a single MLK‐dose and 40–44 hr after the last dose of 4 weeks once daily treatment. The correlations between the effect of a single dose and 4 weeks treatment on area under the curve (AUC) and maximum % fall in FEV 1 were calculated. Results AUC 0–20 min decreased significantly after a single MLK‐dose ( P  = 0.001, CI: 64.9–218.2), but not after 4 weeks of treatment ( P  = 0.080, CI: −12.2 to 200.4). There was a moderate correlation between the effect of a single MLK‐dose and 4 weeks treatment on AUC 0–20 min , r = 0.49 ( P  = 0.011), and maximum % fall in FEV 1 , r = 0.40 ( P  = 0.035). Conclusion The protection provided by a single MLK‐dose against EIB only modestly predicts the effect of regular treatment against EIB in adolescent asthmatics on low‐dose inhaled corticosteroids. If used on a daily base, MLK offered clinically significant protection against EIB in two thirds of adolescents suboptimally controlled by low‐dose ICS. Pediatr Pulmonol. 2016;51:470–477 . © 2015 Wiley Periodicals, Inc.