The Effects of Montelukast on Smokers With Asthma

The Effects of Montelukast on Sputum Cells and Inflammatory Markers in Smokers With Asthma

The purpose of this study is:

1. To compare neutrophilia, eosinophilic inflammatory markers and asthma symptom indices between smokers and non-smokers.
2. To elucidate the mechanism by which cigarette smokers are resistant to corticosteroids.

Many smokers have insufficient control of their symptoms due to inefficacy of ICS in this subpopulation of asthmatics. Cigarette smoking has been shown to stimulate production of cysLTs. CysLTs could activate production of IL-8 for neutrophilia as well as cause eosinophilia in the airway of asthmatics.

LTRAs are felt to be less efficacious than ICS in smokers with asthma. However, LTRA's unique mechanism of action could be particularly efficacious in preventing worsening symptoms and lung function for smokers with asthma. Given this, along with the fact that ICS are less effective in smokers, targeting cysLT could lead to significant clinical benefits for asthmatic smokers.

Data from this study may possibly serve as crucial data for the significant clinical benefits for asthmatic smokers and determination of the mechanism of corticosteroid resistance in smokers with asthma.

Inclusion Criteria:

Asthmatics:

• clinical history of asthma for at least 1 year
• with evidence of reversible airway obstruction,
• two documented FEV1 between 60-85%,
• PC20 < 4mg/ml by methacholine challenge test
• and average baseline β-agonist use of 2 puffs/day

Smokers:

• smoke 1/2 to 2 packs a day
• with a smoking history of 5-30 pack years

Non-smokers:

• Non-smokers will have either never smoked or have stopped smoking cigarettes over 5 years ago

Exclusion Criteria:

• positive HCG (for females)
• have a respiratory tract infection or need oral corticosteroids within the preceding 6 weeks
• history of COPD or respiratory disorder other than asthma
• history of psychiatric illness
• allergy to fluticasone propionate, salmeterol, montelukast or any of their components
• significant, unstable medical condition other than asthma
• history of life-threatening asthma exacerbation requiring intubation and mechanical ventilation in the last ten years