Conditions: Asthma
Keywords: asthma
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 348
Healthy volunteers: no

Brief summary:
The objective of this study is to evaluate the efficacy and safety of vilanterol inhalation powder administered once daily in the evening in adolescent and adult subjects 12 years of age and older with persistent asthma over a 12-week treatment period.

Detailed description:

Arms:
arm 1: Vilanterol inhalation powder once daily + Placebo inhalation powder via Diskus twice daily for 12 weeks arm 2: Placebo inhalation powder via NDPI once daily + Salmeterol inhalation powder twice daily for 12 weeks arm 3: Placebo inhalation powder via NDPI once daily + Placebo inhalation powder via Diskus twice daily for 12 weeks

Interventions: intervention 1: Vilanterol intervention 2: Salmeterol Inhalation Powder intervention 3: Placebo Inhalation Powder NDPI intervention 4: Placebo Inhalation Powder Diskus
Intervention descriptions: intervention 1: Vilanterol inhalation powder inhaled orally once daily for 12 weeks intervention 2: Salmeterol inhalation powder inhaled orally twice daily for 12 weeks intervention 3: Placebo inhalation powder inhaled orally via Novel Dry Powder Inhaler intervention 4: Placebo inhalation powder inhaled orally twice daily for 12 weeks

Protocol document: