Study of montelukast for the treatment of respiratory symptoms of post-respiratory syncytial virus bronchiolitis in children.

RATIONALE: A pilot study (Bisgaard H; Study Group on Montelukast and Respiratory Syncytial Virus. A randomized trial of montelukast in respiratory syncytial virus postbronchiolitis. Am J Respir Crit Care Med 2003;167:379-383) reported the efficacy of montelukast in post-respiratory syncytial virus (RSV) bronchiolitic respiratory symptoms. OBJECTIVES: To evaluate the efficacy and safety of montelukast, 4 and 8 mg, in treating recurrent respiratory symptoms of post-RSV bronchiolitis in children in a large, multicenter study. METHODS: This was a double-blind study of 3- to 24-month-old children who had been hospitalized for a first or second episode of physician-diagnosed RSV bronchiolitis and who tested positive for RSV. Patients (n = 979) were randomized to placebo or to montelukast at 4 or 8 mg/day for 4 weeks (period I) and 20 weeks (period II). The primary end point was percentage symptom-free days (%SFD; day with no daytime cough, wheeze, and shortness of breath, and no nighttime cough). MEASUREMENTS AND MAIN RESULTS: No significant differences were seen between montelukast and placebo in %SFD over period I: mean +/- SD for placebo and for montelukast at 4 and 8 mg were 37.0 +/- 30.7, 38.6 +/- 30.4, and 38.5 +/- 29.9, respectively. Least-squares mean differences (95% confidence interval) between montelukast (4 mg) and placebo and between montelukast (8 mg) and placebo were 1.9% (-2.9, 6.7) and 1.6% (-3.2, 6.5), respectively. Secondary end points were similar across treatments. Both doses were generally well tolerated. During the first two treatment weeks, average %SFD was approximately 29%. In post hoc analyses of patients (n = 523) with persistent symptoms (%SFD < or = 30% over Weeks 1-2), differences in %SFD were seen between montelukast and placebo over Weeks 3-24: difference were 5.7 (0.0, 11.3) for montelukast (4 mg) minus placebo and 5.9 (0.1, 11.7) for montelukast (8 mg) minus placebo. CONCLUSIONS: In this study, montelukast did not improve respiratory symptoms of post-RSV bronchiolitis in children.

Montelukast for treating fall allergic rhinitis: effect of pollen exposure in 3 studies.

BACKGROUND: Montelukast, a potent leukotriene receptor antagonist, is an effective therapy for symptoms of seasonal allergic rhinitis, a disease governed by patients' individual sensitivity and exposure to relevant allergens. OBJECTIVE: To evaluate the relationship of montelukast treatment effect vs pollen exposure in studies conducted during 3 consecutive fall allergy seasons. METHOD: A combined analysis of these multicenter, randomized, double-blind, parallel-group studies was performed; 1 of the 3 studies is presented for the first time in this article. After a placebo run-in period, 1,862 symptomatic patients were randomly assigned to receive either a 10-mg montelukast tablet (n = 929) or placebo (n = 933) once daily for 2 weeks. Pollen exposure was summarized by mean daily weed pollen count. The interaction between treatment effect and pollen exposure was evaluated on the primary efficacy endpoint and daytime nasal symptom score, as rated by patients; also evaluated was the influence of the timing of the 2-week treatment period relative to the peak of the weed pollen season. RESULTS: Montelukast significantly improved daytime nasal symptoms score and individual scores of congestion, rhinorrhea, itching, and sneezing compared with placebo. There was a significant interaction (P < .043) between treatment effect and weed pollen exposure; a larger treatment effect was noted in patients exposed to higher pollen counts. An interaction between treatment effect and timing of treatment in relation to peak pollen season was suggested. CONCLUSIONS: Montelukast significantly improved daytime nasal symptoms score in patients with seasonal allergic rhinitis, and the effect was greater in patients exposed to higher pollen levels.