Study to Evaluate the Effectiveness and Safety of MK-1029 in the Treatment of Persistent Asthma That is Not Controlled With Montelukast (ML) in Adults (MK-1029-011)

The change from baseline in FEV1 at Week 4 following treatment with MK-1029 + ML or placebo + ML was assessed. The pre-bronchodilator FEV1 was evaluated to assess the response to treatment for asthma. The primary efficacy evaluation period was the last week of each treatment period: Period III (Initial Therapy, Week 4) and Period V (Crossover Therapy, Week 4). The change from baseline in FEV1 was evaluated using a longitudinal data analysis (LDA) model with repeated measurements of FEV1, with treatment, visit, treatment-by-visit interaction, and period as fixed effects, and participant as random effect. Baseline FEV1 is defined as the measurement taken before dosing in each treatment period (i. e., at Visit 3 [Week 0], prior to Period III and at Visit 6 [Week 8], prior to Period V). The Baseline Characteristics section shows FEV1 values at baseline.

The number of participants who had at least one adverse event (AE) during study treatment and follow-up was assessed. An AE is defined as any unfavorable and unintended change in the structure, function, or chemistry of the body temporally associated with the use of the SPONSOR's product, whether or not considered related to the use of the product. The number of participants with at least one AE was assessed. The number of participants in any treatment group with at least one AE was assessed.

The number of participants who discontinued study treatment due to an AE was assessed. An AE is defined as any unfavorable and unintended change in the structure, function, or chemistry of the body temporally associated with the use of the SPONSOR's product, whether or not considered related to the use of the product.

The change from baseline in DSS at Week 4 following treatment was assessed. Participants used an electronic diary (e-Diary) to enter their asthma symptom scores every evening. Participants scored daily symptoms (chest discomfort, wheezing, shortness of breath, and cough) by responding to 4 questions: 1) Symptom frequency (0 = None of the time, 6 = All of the time); 2) Bothersomeness (0 = Not bothered, 6 = Severely bothered); 3) Activity limitation (0 = Not limited, 6 = Totally limited); 4) Frequency of activity limitation (0 = None of the time, 6 = All of the time). The average of the 4 scores for overall DSS ranges from 0 to 6 where a higher average indicates greater symptom severity. The average overall DSS was calculated over the week-long assessment periods. The change from baseline in DSS was evaluated using the LDA model with repeated measurements of DSS, with treatment, visit, treatment-by-visit interaction, and period as fixed effects, and participant as random effect.

The change from baseline in SABA use at Week 4 after treatment with MK-1029 + ML or placebo + ML was assessed. Participants used the e-Diary upon arising and before going to sleep to enter the total number of SABA puffs used for asthma relief. The number of SABA puffs recorded was the number of canister actuations (e. g., when SABA use was required and 3 puffs were inhaled, this was recorded as 3). Participants also recorded the number of nebulizer treatments (1 nebulized SABA use = 3 puffs). The average daily number of puffs for an individual participant was calculated over the week-long assessment periods. The change from baseline in SABA use was evaluated using the LDA model with repeated measurements of SABA use, with treatment, visit, treatment-by-visit interaction, and period as fixed effects, and participant as random effect.

The change from baseline in nocturnal awakenings due to asthma at Week 4 after treatment with MK-1029 + ML or placebo + ML was assessed. The participant scored nocturnal awakenings by answering the question, "Did you wake up with asthma symptoms in the middle of the night or upon awakening in the morning?" (No or Yes). Participants recorded in the e-Diary the number of nights per week in which they awakened with asthma, as determined by dividing the number of nights of awakening with asthma by the total number of nights and then multiplying by 7 (standardized to a 7-day period). The change from baseline in nocturnal awakenings was evaluated using the LDA model with repeated measurements of nocturnal awakenings, with treatment, visit, treatment-by-visit interaction, and period as fixed effects, and participant as random effect.

The change from baseline in AM PEF at Week 4 after treatment with MK-1029 + ML or placebo + ML was assessed in 97 participants. Participants performed triplicate AM PEF measurements in the morning upon rising. Participants entered all 3 measurements and the greatest AM PEF value was recorded by the e-Diary. Participants refrained from SABA use within the 4 hours prior to performing PEF measurements. The average AM PEF for an individual participant was calculated over the week-long assessment periods. The change from baseline in AM PEF was evaluated using the LDA model with repeated measurements of AM PEF, with treatment, visit, treatment-by-visit interaction, and period as fixed effects, and participant as random effect.

The change from baseline in PM PEF at Week 4 after treatment with MK-1029 + ML or placebo + ML was assessed. Participants performed triplicate PM PEF measurements in the evening, immediately before study drug administration, at bedtime. Participants entered all 3 measurements and the greatest PM PEF value was recorded by the e-Diary. Participants refrained from SABA use within the 4 hours prior to performing PEF measurements. The average PM PEF for an individual participant was calculated over the week-long assessment periods. The change from baseline in PM PEF was evaluated using the LDA model with repeated measurements of PM PEF, with treatment, visit, treatment-by-visit interaction, and period as fixed effects, and participant as random effect.

The change from baseline in the ACQ score at Week 4, after treatment, was assessed in 97 participants. Participants completed 6 items of the ACQ (i. e., ACQ-6) and provided the average of responses over the past week: 1) Frequency of nocturnal awakenings (0 = Never, 6 = Unable to sleep); 2) Symptom severity (0 = None, 6 = Very severe); 3) Activity limitations (0 = Not limited, 6 = Totally limited); 4) Breathlessness (0 = None, 6 = Very great deal); 5) Wheezing (0 = Not at all, 6 = All the time); 6) Daily SABA use (0 = None, 6 = More than 16 puffs on most days). The ACQ score ranges from 0 to 6 where a lower score indicates greater performance. The investigator reviewed the participant-completed ACQ-6 to ensure its completeness. The change from baseline in the ACQ score was evaluated using the LDA model with repeated measurements of the ACQ score, with treatment, visit, treatment-by-visit interaction, and period as fixed effects, and participant as random effect.