MedWire News: Treatment with the oral leukotriene receptor antagonist montelukast may reduce the effectiveness of allergen-specific immunotherapy (SIT) in children with asthma, contrary to expectations, study findings suggest.
“SIT is the only available potentially curative approach in the management of allergic diseases,” explain Iwona Stelmach (Medical University of Lodz, Poland) and colleagues. “Therapies that modify immune regulation to boost regulatory T cell induction during SIT might further enhance its effectiveness.”
As previous research has shown that treatment with montelukast significantly upregulated interleukin-10 production in children with immunoglobulin E-dependent asthma, the researchers investigate whether treatment with the drug could boost the effectiveness of SIT.
The team enrolled 36 asthmatic children, aged 6–12 years, with house dust mite allergy who had been receiving inhaled corticosteroid (ICS) treatment (budesonide 400–800 µg/day) for at least 7 months.
The children were randomly assigned to receive montelukast 5 mg/day (n=18) or placebo (n=18) in addition to ICSs during the 3-month build-up phase of SIT.
Adjustment of ICS doses to control asthma symptoms were made after this initial SIT build-up phase.
The researchers found that after 12 months of SIT, patients in the placebo group had a significant 16.7% greater reduction in the median daily ICS dose needed to control asthma symptoms than those in the montelukast group.
They also found that treatment with montelukast was associated with impairment in the induction of regulatory T lymphocytes compared with placebo treatment.
However, patients in the placebo group experienced a greater increase in asthma symptoms during the build-up phase of SIT than did the montelukast group, the researchers note.
Stelmach and team comment in the Journal of Allergy and Clinical Immunology: “Our 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.”
They conclude: “When children with asthma are being treated during SIT, routine use of montelukast is not justified.”
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