Male or female patients age 4 -6 years

Diagnosis of mild intermittent bronchial asthma (Step I-II) in the past 6 - 12 months as stated by the investigator:

Use of inhaled beta-2-agonists \< 1/week (max 3 puff /d)

Exacerbation-free interval \> 4 weeks prior to visit 1

The written informed consent of parents after received written and oral information about the aim, purpose and risks of the study must be present

Leukotriene Receptor Antagonists or Steroids in Pre-School Asthma