Montelukast for treating seasonal allergic rhinitis: Effect of pollen counts in 3 fall studies

97 Montelukast for Treating Seasonal Allergic Rhinitis: Effect of Pollen Counts in 3 Fall Studies M. P. Malice, G. Philip, J. van Adelsberg, T. F. Reiss; Merck & Co, Inc, Rahway, NJ. RATIONALE: Symptoms of seasonal allergic rhinitis (SAR) are determined by patients' individual sensitivity and exposure to relevant allergens. This analysis evaluated the relationship of pollen levels to the treatment effect of montelukast for symptoms of SAR. METHODS: Multicenter, randomized, double-blind, parallel-group studies were conducted during 3 consecutive tall allergy seasons. Symptomatic patients age >_15 years were randomly assigned monteluka~st 10-mg (n=929) or placebo (n=933) once-daily for 2 weeks and recorded symptoms daily on diary cards. For analysis, patients were divided into subgroups based on their weed pollen exposure (average of daily pollen counts over their 2week treatment period); subgroups were also defined by the timing of the 2week treatment period relative to the peak of the weed pollen season. RESULTS: Montelukast significantly improved the daytime nasal symptoms score (p 10 grains/m3/24-hr) compared with patients exposed to lower levels (p<0.05). Data also suggested that treatment effect was lowest (as the placebo improvement increased) in patients exposed to low pollen levels after the peak of the pollen season. CONCLUSIONS: Montelukast significantly improved daytime nasal symptoms during fall allergy seasons and this effect was most marked in patients exposed to higher pollen levels. Funding: Merck & Co, lnc 298 InducedF~176176 (F~174 Aer~174 Pr~ Against E x e r c i s e B r o n c h o c o n s t r i c t i o n