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

FEV1 is a measure of lung function and is defined as the maximal amount of air that can be forcefully exhaled in one second. FEV1 was measured electronically using spirometry, prior to study medication and any rescue albuterol (bronchodilator) use. At the end of the 6-week treatment period, FEV1 was measured approximately 24 hours after the participant's last morning dose of study medication and approximately 12 hours after the evening dose of study medication. Trough FEV1 was analyzed using mixed effect analysis of covariance (ANCOVA) model for treatment effects, incorporating fixed effects of baseline, period, age, center, smoking status, and random effect of participant. Intent-to-Treat Population is defined as all participants who were randomized and received at least one dose of study drug.

The PEF is a measure of lung function and measures how fast a person can breathe out. Trough PEF was measured every morning prior to study medication dose and any rescue albuterol (bronchodilator) use. Participants recorded PEF in a daily electronic diary (eDiary). Daily trough morning PEF was averaged over the last 3 weeks of the 6-week treatment period, and analyzed using mixed effect ANCOVA model for treatment effects, incorporating fixed effects of baseline, period, age, center, smoking status, and random effects of participant.

The PEF is a measure of lung function and measures how fast a person can breathe out. PEF was measured every evening prior to study medication dose and any rescue albuterol (bronchodilator) use. Participants recorded PEF in a daily eDiary. Daily evening PEF was averaged over the last 3 weeks of the 6-week treatment period, and analyzed using mixed effect ANCOVA model for treatment effects, incorporating fixed effects of baseline, period, age, center, smoking status, and random effects of participant.

The PEF is a measure of lung function and measures how fast a person can breathe out. PEF was measured every morning and evening prior to study medication dose and any rescue albuterol (bronchodilator) use. Participants recorded PEF in a daily eDiary. Daily average of morning and evening PEF was averaged over the last 3 weeks of the 6-week treatment period, and analyzed using mixed effect ANCOVA model for treatment effects, incorporating fixed effects of baseline, period, age, center, smoking status, and random effects of participant. This outcome measure explored the efficacy between GSK2190915 and montelukast due to the dosing time difference.

Daytime and night time asthma symptoms were recorded every evening at bedtime and every morning upon rising, respectively, before taking any rescue or study medication and before assessing the PEF. Symptoms were recorded on scales ranging from '0' (implying no symptoms) to either 5 (for daytime symptoms) or 4 (for night time symptoms) (implying severe symptoms). Participants recorded the symptoms in a daily eDiary. 24-hour period asthma symptom scores were averaged over the last 3 weeks of the 6-week treatment period, and analyzed using mixed effect ANCOVA model for treatment effects, incorporating fixed effects of baseline, period, age, center, smoking status, and random effects of participant.

A SABA (albuterol) was provided to participants as a rescue medication, to use as needed for symptomatic relief of asthma symptoms. Participants were required to record their albuterol use in the morning and in the evening. Participants recorded the number of inhalations of rescue medication in a daily eDiary. The daily rescue SABA use was averaged over the last 3 weeks of the 6-week treatment period, and analyzed using mixed effect ANCOVA model for treatment effects, incorporating fixed effects of baseline, period, age, center, smoking status, and random effects of participant.

Daytime asthma symptoms were recorded every evening at bedtime, before taking any rescue or study medication and before assessing the PEF. Symptoms were recorded on a 6-point scale ranging from '0' (implying no symptoms) to 5 (implying severe symptoms). Participants recorded the symptoms in a daily eDiary. The number of days when symptoms were not experienced ("symptom-free days") during the last 3 weeks of the 6-week treatment period were counted, and percentage calculated by dividing by 21 and multiplying by 100. Analysis was done using mixed effect ANCOVA model for treatment effects, incorporating fixed effects of baseline, period, age, center, smoking status, and random effects of participant.

Night time asthma symptoms were recorded every morning upon rising, before taking any rescue or study medication and before assessing the PEF. Symptoms were recorded on a 5-point scale ranging from '0' (implying no symptoms) to 4 (implying severe symptoms). Participants recorded the symptoms in a daily eDiary. The number of nights when symptoms were not experienced ("symptom-free nights") during the last 3 weeks of the 6-week treatment period were counted, and percentage calculated by dividing by 21 and multiplying by 100. Analysis was done using mixed effect ANCOVA model for treatment effects, incorporating fixed effects of baseline, period, age, center, smoking status, and random effects of participant.

Albuterol was provided as a rescue medication, and participants were required to record rescue medication use in the morning and in the evening. Participants recorded the number of inhalations of rescue medication in a daily eDiary. The number of days when rescue medication was not used ("rescue-free days") during the last 3 weeks of the 6-week treatment period were counted, and percentage calculated by dividing by 21 and multiplying by 100. Analysis was done using mixed effect ANCOVA model for treatment effects, incorporating fixed effects of baseline, period, age, center, smoking status, and random effects of participant.

Albuterol was provided as a rescue medication, and participants were required to record rescue medication use in the morning and in the evening. Participants recorded the number of inhalations of rescue medication in a daily eDiary. The number of nights when rescue medication was not used ("rescue-free nights") during the last 3 weeks of the 6-week treatment period were counted, and percentage calculated by dividing by 21 and multiplying by 100. Analysis was done using mixed effect ANCOVA model for treatment effects, incorporating fixed effects of baseline, period, age, center, smoking status, and random effects of participant.

Night time asthma symptoms were recorded every morning upon rising, before taking any rescue or study medication and before assessing the PEF. Symptoms were recorded on a 5-point scale: 0 = no symptoms during the night, 1 = symptoms causing to wake once, 2 = symptoms causing to wake twice or more, 3 = symptoms causing to be awake most of the night, 4 = could not sleep due to severe symptoms. Participants recorded the symptoms in a daily eDiary. The number of nights with no awakenings due to asthma during the last 3 weeks of the 6-week treatment period were counted, and percentage calculated by dividing by 21 and multiplying by 100. Analysis was done using mixed effect ANCOVA model for treatment effects, incorporating fixed effects of baseline, period, age, center, smoking status, and random effects of participant.

Participants were withdrawn if they met any of the following three criteria for 'lack of efficacy': 1) Clinic FEV1 below the FEV1 'Stability Limit' value, 2) During any consecutive 7-day period, the participant experienced PEF fallen below the PEF 'Stability Limit' for more than 3 days, or if >= 12 inhalations per day of albuterol were used for more than 2 days, and 3) Ashtma exacerbation. The number of withdrawals due to lack of efficacy were summarized for each treatment and Fisher's Exact test was used for comparison with placebo add-on. Withdrawals occurring during active washout periods are not included.