Background Controlled trials suggest that leukotriene receptor antagonists
can improve lung function and reduce requirement for oral or inhaled cortic
osteroids in patients with asthma. We aimed to assess whether montelukast,
a leukotriene receptor antagonist. can improve symptoms or lung function in
patients with chronic asthma with symptoms already taking corticosteroids.
Methods We did a double-blind, placebo-controlled, crossover, randomised ad
d-on study in which 100 patients with asthma and symptoms despite treatment
with inhaled corticosteroids and additional therapy were given 10 mg monte
lukast sodium for 14 days in an outpatient clinic setting. Outcome measures
were symptoms and peak flow diaries.
Findings 72 patients had diary data for analysis. Compared with placebo. ad
dition of montelukast did not result in any significant change in symptom s
cores (mean difference between the last 7 days of each treatment period 0.0
5: 95% CI -0.86 to 1.14), rescue inhaled beta (2) agonist use (mean differe
nce in puffs per day 0.41; -0.29 to 0.57), or twice daily peak expiratory f
low (PEF) measurements (mean difference in morning PEF 1.18 L/min; -14.29 t
o 17.14). and mean difference in evening peak flow (-0.50; -17.42 to 12.86)
. When treatment response was defined as a 15% or greater increase in mean
peak flow readings, there were four responders to montelukast and seven res
ponders to placebo.
Interpretation Based on PEF data from our previous studies of a similar pat
ient group we would have expected to detect changes of more than 5%. Used a
s additional therapy in a hospital outpatient clinic setting, montelukast d
id not provide such additional benefit in patients with moderate or severe