Inclusion Criteria:

• Healthy.
• Male or female 18 to 65 years of age inclusive.
• Non-childbearing women or women of child bearing potential who agree to use contraception
• Subject has had their CYP2D6 genotype confirmed and can be included in either of the following parts:
• Part 1: may include extensive, intermediate and ultra-rapid metabolizers
• Part 2: includes only poor (no enzyme activity) metabolizers, with previously confirmed phenotype
• Body Mass Index within the range 18 - 30 kg/m2 (inclusive).
• Capable of giving written informed consent
• Normal ECG;
• Normal lung function.
• Non-smokers (never smoked or not smoking for >6 months with <10 pack years history (Pack years = (cigarettes per day smoked/20) x number of years smoked))
• A signed and dated written informed consent is obtained from the subject
• The subject is capable of giving informed consent
• Available to complete the study

Exclusion Criteria:

• Any clinically important abnormality identified at the screening medical assessment (physical examination/medical history), clinical laboratory tests, or ECG (12-lead). 24hr Holter monitoring outside normal limits.
• A history of breathing problems (i.e. history of asthmatic symptomatology).
• Abnormal ECG.
• Abnormal blood pressure.
• Abnormal heart rate
• The subject has a positive pre-study drug/alcohol screen.
• A positive pre-study Hepatitis B surface antigen or positive Hepatitis C antibody result within three months of screening.
• A positive test for HIV antibody (if determined by the local SOPs).
• History of high alcohol consumption within three months of the study
• The subject has participated in a clinical trial and has received an IP within the following time period prior to the first dosing day in the current study: 30 days, five half-lives or twice the duration of the biological effect of the IP (whichever is longer).
• Exposure to more than four new chemical entities within 12 months prior to the first dosing day.
• Use of prescription or non-prescription drugs, (except for simple analgesics e.g. paracetamol), including vitamins, herbal and dietary supplements (including St John's Wort) within seven days (or 14 days if the drug is a potential enzyme inducer) or five half-lives (whichever is longer) prior to the first dose of study medication
• History of sensitivity to any of the study medications, or components thereof or a history of drug or other allergy that, in the opinion of the investigator or GSK Medical Monitor, contraindicates their participation.
• Where participation in the study would result in donation of blood or blood products in excess of 500mL within a 56 day period.
• Unwillingness or inability to follow the procedures outlined in the protocol.
• Urinary cotinine levels indicative of smoking or history of regular use of tobacco- or nicotine-containing products prior to screening.
• The subject is unable to use the novel dry powder inhaler correctly.
• The subject has a known allergy or hypersensitivity to milk protein or the excipients magnesium stearate and lactose monohydrate.