There are three elements to this study:

• Part A: Single dose escalation in healthy subjects. 6 dose levels of QAK423 are planned in healthy volunteers.
• Part B: Single dose escalation in patients with mild/moderate COPD. 3 dose levels of QAK423 are planned in COPD patients.
• Part C: Titrated repeat dosing for a maximum of 14 days in mild/moderate COPD patients.

Repeat dosing is planned in COPD patients.

Inclusion Criteria:

Part A:

• Healthy, male subjects aged 18-55 years of age able to provide written informed consent prior to study participation and determined as in good health by past medical history, physical examination, ECG, laboratory tests and urinalysis.

Parts B and C:

• Male or female (post menopausal or surgically sterilized) patients with COPD, aged 40-75 years, with a smoking history of at least 10 pack years (i.e. smokers or ex-smokers).
• Diagnosis of mild or moderate COPD, according to the GOLD guidelines.
• Post-bronchodilator FEV1 at screening 50-80% of predicted.
• No COPD exacerbations within the 3 months prior to dosing, no concomitant lung disease such as asthma, requirement for long term oxygen treatment or history of lung reduction surgery.
• No medical conditions that may jeopardize the subjects participation in the study
• Weigh less than 100 kg

Exclusion Criteria:

• Use of any prescription drug or over-the-counter (OTC) medication within 2 weeks prior to dosing.
• History of acute or chronic bronchospastic disease (including asthma and chronic obstructive pulmonary disease, treated or not treated).
• Participation in any clinical investigation within 4 weeks prior to dosing or longer if required by local regulation.
• History of clinically significant drug allergy. A known hypersensitivity to the study drug or drugs similar to the study drug.

Other protocol-defined inclusion/exclusion criteria may apply