The aim of the present study is to compare the efficacy of inhaled ciclesonide in pre-school children. Ciclesonide will be inhaled once daily, using one of three dose levels and tested versus placebo. The study duration consists of a baseline period (2 to 4 weeks) and a treatment period (24 weeks). The study will provide further data on safety and tolerability of ciclesonide.

Main Inclusion Criteria:

• Written informed consent by the parents or legal guardians of the patient
• Outpatients
• Good health with the exception of asthma
• Documented diagnosis of asthma for more than 6 months
• Use of rescue medication only or pretreatment with a controller drug

Main Exclusion Criteria:

• Concomitant severe diseases
• Diseases contraindicated for the use of inhaled steroids
• Other relevant lung diseases causing impairment in pulmonary function
• Recurrent, episodic wheezing only
• History of life-threatening asthma
• History of any mechanical ventilation
• Clinically relevant abnormal laboratory values suggesting an unknown disease and requiring further clinical evaluation
• Premature birth (< 32 weeks gestation)