Study B2C112060: A Study of the Efficacy and Safety of Vilanterol Inhalation Powder in Adults and Adolescents With Persistent Asthma

The time span during which the participants did not have to take any rescue bronchodilator (medication intended to relieve symptoms immediately) was considered to be a rescue-free period. The Baseline value was derived from the last 7 days of the daily diary prior to the randomization of the participant (including the day of randomization). Change from Baseline is calculated as the value at Weeks 1-12 minus the value at Baseline. Analysis was performed using ANCOVA with covariates of Baseline, region, sex, age, and treatment.

Participants who were symptom free for 24-hour periods during the12-week treatment period were assessed. The Baseline value was derived from the last 7 days of the daily diary prior to the randomization of the participant (including the day of randomization). Change from Baseline is calculated as the value at Weeks 1-12 minus the value at Baseline. Analysis was performed using ANCOVA with covariates of Baseline, region, sex, age, and treatment.

FEV1 is a measure of lung function and is defined as the volume of air that can be forcefully exhaled in one second. The individual serial FEV1 is calculated from the pre-dose FEV1 and post-dose FEV1 measurements at 5, 15, 30, and 60 minutes (min) and 2, 3, 5, 11, 12, 12.5, 13, 14, 16, 20, 23, and 24 hours, relatively, on Treatment Day 84 (Week 12). The Baseline value was the Day 1 pre-dose FEV1 measurement. Change from Baseline was calculated as the value of the individual serial FEV1 taken at Week 12 minus the Baseline value. Analysis was performed using ANCOVA with covariates of Baseline FEV1, region, sex, age, and treatment. Analysis was performed separately for each planned time point.

PEF is defined as the maximum airflow during a forced expiration beginning with the lungs fully inflated. Trough PEF is the PEF measured approximately 24 hours after the last administration of study drug. The Baseline value is the average value of the last 7 days of daily PM PEF prior to randomization. Change from Baseline in trough PM PEF was calculated as the averaged value of all daily PM PEF for Week 1 to Week 12 minus the value at Baseline. Analysis was performed using ANCOVA with covariates of Baseline, region, sex, age, and treatment.

PEF is defined as the maximum airflow during a forced expiration beginning with the lungs fully inflated. Trough PEF is the PEF measured approximately 24 hours after the last administration of study drug. The Baseline value is the average value of the last 7 days of daily AM PEF prior to randomization. Change from Baseline in trough AM PEF was calculated as the averaged value of all daily AM PEF for Weeks 1 to Week 12 minus the value at Baseline. Analysis was performed using ANCOVA with covariates of Baseline, region, sex, age, and treatment.

The number of participants with a >=12% and >=200 mL increase from Baseline in FEV1 (the maximal amount of air that can be forcefully exhaled in one second) was evaluated on Day 1 and Week 12 for the time to a >=12% increase from Baseline (at the 5 minutes (min), 15 min, 30 min, 1hour (hr), and 2 hr nominal time points. Participants who did not achieve a >=12% and >=200 mL increase from Baseline in FEV1 over this time period were considered censored.

At the end of Week 4 and Week 12, the Global Assessment of Change Questionnaire, which assesses changes in asthma symptoms and rescue medication use, was completed by participants using the following scale: asthma symptom (AS) change: much better, somewhat better, a little better, the same, a little worse, somewhat worse, much worse; rescue medication use (RMU): much less often , somewhat less often , a little less often , the same , a little more often , somewhat more often , much more often.