Study HZA106829: Efficacy/Safety Study of Fluticasone Furoate/Vilanterol (GW642444) in Adult and Adolescent Asthmatics

FEV1 is a measure of lung function and is defined as the maximal amount of air that can be forcefully exhaled in one second. Trough FEV1 is defined as the clinic visit (pre-bronchodilator and pre-dose) FEV1 measurement taken at the clinic visit while still on treatment. Pre-dose and pre-rescue albuterol/salbutamol trough FEV1 was measured electronically by spirometry in the evening at the Baseline (BL) through Week 24 clinic visits. The highest of 3 technically acceptable measurements was recorded. BL was the pre-dose value obtained at Visit 3. Change from BL was calculated as the Week 24 value minus the Baseline value. The analysis was performed using an Analysis of Covariance (ANCOVA) model with covariates of BL trough FEV1, country, sex, age, and treatment group.The last observation carried forward (LOCF) method was used to impute missing data, in which the last non-missing post-BL on-treatment measurement at scheduled clinic visits was used to impute the missing measurements.

FEV1 is a measure of lung function and is defined as the maximal amount of air that can be forcefully exhaled in one second. Serial FEV1 measurements were taken electronically by spirometry at the Baseline and Week 24 clinic visits. Weighted mean was calculated using the 24-hour serial FEV1 measurements that included the pre-dose assessment (within 5 minutes prior to dosing) and the post-dose assessments after 5, 15, and 30 minutes and 1, 2, 3, 4, 5, 12, 16, 20, 23, and 24 hours. At each time point, the highest of 3 technically acceptable measurements was recorded. Baseline was the value obtained at Visit 3. Change from Baseline was calculated as the average Week 24 FEV1 value minus the Baseline value.

The number of inhalations of rescue bronchodilator, albuterol/salbutamol inhalation aerosol, used during the day and night was recorded by the participants in a daily electronic diary (eDiary). Similarly, asthma symptoms were recorded in a daily eDairy by the participants every day in the morning and evening before taking any rescue or study medication and before the peak expiratory flow measurement. A 24-hour period in which a participant's responses to both the morning and evening assessments indicated no use of rescue medication/symptoms was considered to be rescue free/symptom free. The Baseline value was derived from the last 7 days of the daily eDiary prior to the randomization of the participant. Change from Baseline was calculated as the averaged value during the 24-week Treatment Period minus the Baseline value.

The AQLQ is a disease-specific, self-administered quality of life questionnaire used to evaluate the impact of asthma treatments on the quality of life of asthma sufferers. The AQLQ for 12 years and older (AQLQ [+12]) is a modified version of the AQLQ for use in asthma patients between the age of 12 and 70. The AQLQ contains 32 items in 4 domains: activity limitation (11 items), symptoms (12 items), emotional function (5 items), and environmental stimuli (4 items). For the 32 items on the questionnaire, the response format consists of a seven-point scale, where a value of 1 indicates "total impairment" and a value of 7 indicates "no impairment." The AQLQ total score is defined as the average of the scores from all 32 questions; thus, the total score ranges from 1 (indicates "total impairment") to 7 (indicates "no impairment"). Baseline was the total score obtained at Visit 3. Change from Baseline was calculated as the total score at Weeks 12 and 24 minus the total score at Baseline.

FEV1 is a measure of lung function and is defined as the maximal amount of air that can be forcefully exhaled in one second. 12-hour post-dose FEV1 measurements were taken electronically by spirometry at the Week 24 clinic visit. The highest of 3 technically acceptable measurements was recorded.

FEV1 is a measure of lung function and is defined as the maximal amount of air that can be forcefully exhaled in one second. Serial FEV1 measurements were taken electronically by spirometry at Baseline. Weighted mean was calculated using the 4-hour serial FEV1 measurements that included the pre-dose assessment (within 5 minutes prior to dosing) and post-dose assessments after 5, 15, and 30 minutes and 1, 2, 3, and 4 hours. At each time point, the highest of 3 technically acceptable measurements was recorded. Baseline was the value obtained at Visit 3. Change from Baseline was calculated as the average Week 24 FEV1 value minus the Baseline value.

PEF is a measure of lung function and is defined as the maximum airflow during a forced expiration beginning with the lungs fully inflated. PEF was measured by the participants using a hand-held electronic peak flow meter each morning and evening prior to the dose of study medication and any rescue albuterol/salbutamol inhalation aerosol use. Trough PEF is the PEF measured approximately 24 hours after the last administration of study drug. Change from Baseline (defined as the last 7 days prior to randomization of the participants) was calculated as the value of the averaged daily trough AM/PM PEF over 12 weeks and 24 weeks of the 24-week Treatment Period (at Weeks 12 and 24) minus the Baseline value.

The number of participants whose primary reason for withdrawal was lack of efficacy was analyzed.

The ACT is a 5-item questionnaire developed as a measure of the participant's asthma control. Questions are designed to be self-completed by the participant and include the following: In the past 4 weeks, "How much of the time did your asthma keep you from getting as much done at work, school or at home?", "How often have you had shortness of breath?", "How often did your asthma symptoms wake you up at night or earlier than usual in the morning?", "How often have you used your rescue inhaler or nebulizer medication (such as albuterol)?" and "How would you rate your asthma control"? The ACT total score is defined as the sum of the scores from all 5 questions, provided all questions have been answered; thus, the total score ranges from 5 (poor control of asthma) to 25 (complete control of asthma). A score of 20 or higher indicates well-controlled asthma. Change from Baseline was calculated as the total score at Week 12 and Week 24/Early Withdrawal minus the total score at Baseline.

At the end of Week 4, Week 8, and Week 24/Early Withdrawal, the Global Assessment of Change Questionnaire that assesses changes in asthma symptoms (AS) and rescue medication use (RMU) was completed by the participants. The number of participants who chose the following answers to the questionnaire were determined: much better, somewhat better, a little better, the same, a little worse, somewhat worse, much worse (to assess the changes in asthma symptoms); much less often, somewhat less often, a little less often, the same, a little more often, somewhat more often, much more often (to assess the changes in the frequency of rescue medication use).

All unscheduled asthma-related visits to a physician's office, visits to urgent care, visits to the emergency department, and hospitalizations (ICU=intensive care unit; GW=general ward) associated with severe asthma exacerbations or other asthma-related healthcare issues were recorded.