Asthma and lower airway diseaseMontelukast treatment may alter the early efficacy of immunotherapy in children with asthma

BackgroundAllergen-specific immunotherapy (SIT) is the only available potentially curative approach in the management of allergic diseases. Therapies that boost regulatory T cell induction during SIT might further enhance its effectiveness.ObjectiveThe purpose of this study was to assess the effect of montelukast treatment on early clinical and immunologic effects of allergen-specific immunotherapy in children with asthma.MethodsIt was a randomized, double-blind, placebo-controlled trial conducted in 36 children with asthma and allergy to house dust mites who required from 400 to 800 μg of inhaled budesonide per day during the 7-month run-in period. Patients were randomly allocated to receive 5 mg montelukast daily (n = 18) or placebo (n = 18) as an addition to inhaled corticosteroid (ICS) treatment during the 3-month build-up phase of SIT, when modification of ICS doses was not allowed. During the 7 months of the maintenance phase of SIT, ICS doses were adjusted to control the asthma symptoms.ResultsAfter 12 months of SIT, a reduction of the median daily ICS dose, necessary to control asthma symptoms, was 16.7% grater in patients from the placebo group than in patients from the montelukast group. Intervention with montelukast significantly impaired the induction of regulatory T lymphocytes. During the build-up phase of SIT, patients in the placebo group frequently experienced an increase in asthma symptoms leading to exclusions from the per protocol population.ConclusionOur study failed to show a beneficial effect of montelukast on SIT. In fact, quite the opposite occurred: compared with placebo, montelukast intervention led to less effectiveness of SIT.