Safety and Efficacy Study of Adding GSK2190915 to Low Dose Inhaled Corticosteroid Treatment for Asthma Subjects > or = 12 Years of Age

A Randomized, Double-Blind, Double-Dummy, Placebo-Controlled, Five-Treatment, Four 6-Week Period Cross-Over, Multi-Center Study to Evaluate the Effect of Adding GSK2190915 100mg, GSK2190915 300mg, Montelukast 10mg or Placebo Tablets Once Daily or Salmeterol 50mcg Inhalation Powder Twice Daily to Fluticasone Propionate 100mcg Inhalation Powder Twice Daily in Uncontrolled Asthmatic Subjects ≥ 12 Years of Age

The primary objective of this study is to evaluate the efficacy and safety of adding GSK2190915 100mg, GSK2190915 300mg or placebo tablets administered once daily to fluticasone propionate 100mcg inhalation administered twice daily in uncontrolled asthmatic subjects > or = 12 years of age over the course of 6 weeks treatment.

The secondary objectives are to undertake an exploratory analysis of the efficacy and safety of adding montelukast 10mg administered once daily or salmeterol 50mcg administered twice daily to fluticasone propionate 100mcg inhalation administered twice daily and to investigate the pharmacokinetics and pharmacodynamics of GSK2190915 in uncontrolled asthmatic subjects > or = 12 years of age over the course of 6 weeks treatment.

Inclusion Criteria:

• Age: 12 years of age or older
• Non-, former or current smokers with a documented smoking history of ≤ 10 pack years
• Asthma diagnosis as defined by the National Institutes of Health
• Best FEV1 of 50% to <80% of the predicted normal value
• Post-albuterol FEV1/FVC ratio of >0.70 at Visit 1/1a (between 5:00AM and 12:00 noon)
• ≥ 12% and ≥200mL reversibility of FEV1
• Must have been using FP 100mcg inhalation powder BID for at least 2 weeks just prior to Visit 1.
• Must be able to replace their current short-acting beta2-agonists with albuterol inhalation aerosol
• Must be able and willing to give written informed consent to take part in the study.
• Must be able and willing to comply with all aspects of the study including completion of daily e-Diary.

Exclusion criteria:

• History of life-threatening asthma
• Recent asthma exacerbation
• Concurrent respiratory disease
• Recent respiratory infection
• Liver disease
• Other concurrent diseases/abnormalities
• Oral candidiasis
• Drug allergy
• Milk protein allergy
• Immunosuppressive Medications
• Administration of systemic, oral or depot corticosteroids within 12 weeks of Visit 1
• OATP1B1 substrates within 4 weeks of Visit 1
• Cytochrome P450 3A4 (CYP 3A4) Inhibitors
• Cytochrome P450 3A4 (CYP 3A4) Inducers
• Investigational Medications
• Compliance: any infirmity, disability, or geographical location which seems likely (in the opinion of the Investigator) to impair compliance with any aspect of this study protocol
• Affiliation with Investigator's Site