The study is designed to obtain safety and efficacy data on three dose levels of indacaterol when delivered via an SDDPI in patients with persistent asthma. All patients will receive 1 day of treatment with each of the following: indacaterol 150 µg, indacaterol 300 µg, indacaterol 600 µg, placebo, and formoterol. Each treatment day will be followed by a washout-period of 1 week

Inclusion Criteria:

• Males and females 12 - 75 years of age with a diagnosis of persistent asthma
• Daily treatment with a bronchodilator and daily dose of at least 100 µg beclomethasone dipropionate or equivalent
• FEV1 at Visit 1 at least 50% of the predicted normal value
• FEV1 reversibility at least 15%

Exclusion Criteria:

• Use of tobacco products within 6 months prior to Visit 1 or a smoking history of more than 10 pack years
• Chronic Obstructive Pulmonary Disease (COPD)
• Seasonal allergy where asthma is likely to deteriorate during the period of the study
• Emergency room treatment for an acute asthma attack within the previous 6 weeks or hospitalized within the previous 6 months
• A respiratory tract infection within the previous 6 weeks Other protocol-defined exclusion criteria may apply