Randomized Open Comparison of Montelukast and Sublingual Immunotherapy as Add-on Treatment in Moderate Persistent Asthma Due to Birch Pollen

Background: No studies have directly compared the effects of immunotherapy and antileukotrienes due to the long time required to appreciate the clinical effects of immunotherapy. We compared the effect of montelukast (MK) and SLIT added to standard therapy in moderate asthma over 5 years. Methods: Open randomized controlled trial. Patients with moderate asthma (and rhinitis) solely due to birch pollen were randomized to receive either MK (10 mg/d) or birch sublingual immunotherapy (SLIT) in the pollen seasons, in addition to formoterol/fluticasone. All the patients also received salbutamol and cetirizine as rescue medications. Asthma and rhinitis symptoms were recorded on diary cards from February to May at baseline and after 3 and 5 years of study. In-season nasal eosinophils and bronchial hyperresponsiveness were also evaluated. Results: Thirty-three adult patients were enrolled and 29 completed the study. The groups were homogeneous at baseline. Bronchial and nasal symptom scores were lower at 3 and 5 years compared to baseline in the SLIT group. Bronchial hyperresponsiveness and bronchodilator use decreased significantly in both groups at 5 years, but only in the SLIT group at 3 years. In the SLIT group there was a significant decrease in nasal eosinophils compared to baseline and to the MK group. Conclusion: In patients with birch pollen induced moderate asthma and rhinitis, the addition of SLIT provides a greater clinical benefit than that of MK.