A randomized study comparing the effect of loratadine added to montelukast with montelukast, loratadine, and beclomethasone monotherapies in patients with chronic asthma.

Background: Loratadine added to montelukast has been suggested to improve endpoints of asthma.

Objective: This study investigated the additive effects of concomitant montelukast and loratadine when compared with montelukast, loratadine, and inhaled beclomethasone monotherapies in asthma. Methods. Patients (N = 406) were 15 to 65 years of age with a forced expiratory volume in 1 second (FEV(1))-predicted of 50% to 85%, FEV(1) reversibility > or = 15%, and a minimal level of daytime symptoms and beta -agonist use. This three-part 2X2 crossover-study consisted of two double-blind 6-week treatment periods where patients were administered once daily oral montelukast 10 mg, loratadine 10 mg, montelukast 10 mg + loratadine 10 mg, or twice daily inhaled beclomethasone 200 mu g. A subsequent 48-week extension study compared montelukast + loratadine with beclomethasone. The primary endpoint was the percentage change from baseline in FEV(1).

Results: Over 6 weeks of double-blind treatment, significant improvements (p < 0.05) in the primary endpoint of FEV(1) were seen for montelukast + loratadine versus loratadine (least-square mean percentage-point difference of 5.8%), beclomethasone versus montelukast + loratadine (2.35%), montelukast versus loratadine (5.94%), and beclomethasone versus montelukast (4.65%); a numerical improvement (p = 0.054) was seen for montelukast + loratadine versus montelukast (1.60%). Significant improvements for montelukast + loratadine versus montelukast were seen in some secondary endpoints (evening peak expiratory flow, nocturnal asthma symptom score, nocturnal awakenings, and asthma-specific quality of life) but not others. Significant improvements in most endpoints except daytime asthma symptoms score were seen for montelukast + loratadine versus loratadine. In the extension study, both montelukast + loratadine and beclomethasone improved several endpoints. All treatments were generally comparable in the percentage of patients with clinical and laboratory adverse experiences.

Conclusion: In this study, the addition of loratadine to montelukast produced a small numerical, but not statistically significant, improvement in FEV(1) and, in general, no consistent improvement in other asthma endpoints. No improvement of montelukast + loratadine versus beclomethasone was seen in any endpoint.