Study to Evaluate the Efficacy and Safety of MEDI9929 (AMG 157) in Adult Subjects With Inadequately Controlled, Severe Asthma

Asthma exacerbation is defined as worsening of asthma that leads to any of the following: use of systemic corticosteroids for at least 3 days, an emergency department visit due to asthma that required systemic corticosteroids, and an inpatient hospitalization due to asthma. Reduction in AER was evaluated in pre-specified subpopulations (blood eosinophil count [eosinophilic and non-eosinophilic], T helper cell 2 [Th2] status [high and low], Fraction of exhaled nitric oxide [FENO] [high and low], serum periostin [high and low], current post bronchodilator forced expiratory volume in 1 second [Post-BD FEV1] reversibility- yes, allergic and non-allergic) of asthma. The annual AER was presented as the total number of exacerbations for the treatment group divided by the total duration of person follow-up. Also, the high or low was determined using median value.

Forced expiratory volume in 1 second and forced vital capacity measures taken before bronchodilator use were reported.

Forced expiratory volume in one second (FEV1) was evaluated in pre-specified subpopulations of asthma. The data presented in the below table for this outcome measure is for pre-bronchodilator FEV1.

Forced expiratory volume in 1 second and forced vital capacity measures taken after bronchodilator use were reported.

Asthma symptoms during night time and daytime are recorded by the participant in the asthma daily diary. Overall symptom score is the average of scores of daytime severity, daytime frequency, and nighttime severity symptoms. The daytime frequency and severity items are scored from 0 to 4, where a higher score indicates greater frequency/severity and nighttime severity item is scored from 0 to 4 , where a higher score indicates greater severity. Overall symptom score ranges from 0 to 4, where lower score indicates better asthma symptom while, higher score indicates worse asthma symptom.

Asthma symptoms during night time and daytime are recorded by the participant in the asthma daily diary. Symptom score values for night time assessment is 0 (no asthma symptom) to 3 (unable to sleep because of asthma) and symptom score values for day time assessment is 0 (no asthma symptom) to 3 (unable to do normal activities due to asthma). Total asthma symptom score is the sum of the daytime and night time score (0 to 6). Lower score (0) is indicating better asthma symptom, while higher score (6) is indicating worse asthma symptom.

The ACQ is a patient-reported questionnaire assessing asthma symptoms (ie, night-time waking, symptoms on waking, activity limitation, shortness of breath, wheezing) and daily rescue bronchodilator use and FEV1. The ACQ-6 is a shortened version of the ACQ that omits the FEV1 measurement from the original ACQ score. Questions are weighted equally and scored from 0 (totally controlled) to 6 (severely uncontrolled).

A severe asthma exacerbation is defined as an event that resulted in hospitalization. The severe AER was presented as the total number of exacerbations for the treatment group divided by the total duration of person follow-up.

Asthma exacerbation is defined as worsening of asthma that leads to use of systemic corticosteroids for at least 3 days, an emergency department visit due to asthma that required systemic corticosteroids, and an inpatient hospitalization due to asthma. Time to first asthma exacerbation was reported.

Asthma exacerbation is defined as worsening of asthma that leads to use of systemic corticosteroids for at least 3 days, an emergency department visit due to asthma that required systemic corticosteroids, and an inpatient hospitalization due to asthma. Time to first severe asthma exacerbations (hospitalization) were reported.

Asthma exacerbation is defined as worsening of asthma that leads to use of systemic corticosteroids for at least 3 days, an emergency department visit due to asthma that required systemic corticosteroids, and an inpatient hospitalization due to asthma.

Asthma exacerbation is defined as worsening of asthma that leads to use of systemic corticosteroids for at least 3 days, an emergency department visit due to asthma that required systemic corticosteroids, and an inpatient hospitalization due to asthma. Participants with severe asthma exacerbations (hospitalization) were reported.

The AQLQ(S) +12 is a 32-item questionnaire that measures the health-related quality of life experienced by asthma participants. The questionnaire comprises 4 separate domains (symptoms, activity limitations, emotional function, and environmental stimuli) scaled on a 7-point scale ranging from 7 (no impairment) to 1 (severe impairment).

European Quality of Life-5 Dimensions-5 Level (EQ-5D-5L) is a standardized measure of health status of the participant. The first component is a descriptive system of the respondent's health comprised of the following 5 participant-reported dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Each dimension has 5 levels: no problems, slight problems, moderate problems, severe problems, and extreme problems. The responses are used to derive the health state index scores using the United Kingdom (UK) algorithm, with scores ranging from -0.594 to 1. A higher score indicates better health state. The second component is a self-perceived health score which is assessed using a visual analogue scale (VAS) that ranged from 0 to 100, where 0 indicated the worst health you can imagine and 100 indicated the best health you can imagine.

The total amount of study drug exposure (in milligram) for the entire study period was summarized.

An adverse event is any unfavourable and unintended signs (including abnormal laboratory findings), symptoms, or diseases temporally associated with use of medicinal product, whether or not considered related to medicinal product. Serious adverse event is any adverse event that resulted in death, life-threatening, inpatient hospitalization or prolongation of existing hospitalization, persistent or significant disability or incapacity, is a congenital anomaly/birth defect in offspring of a study participant, is an important medical event that may jeopardize the participant or may require medical intervention. TEAEs are defined as events present at baseline that worsened in intensity after administration of study drug or events absent at baseline that emerged after administration of study drug, for the period until and including the follow-up period (Week 64).

Adverse events observed in participants with clinically significant vital signs abnormalities were assessed.

An abnormal laboratory finding which required an action or intervention by the investigator, or a finding judged by the investigator to represent a change beyond the range of normal physiologic fluctuation were reported as an adverse event. Laboratory evaluations of blood and urine samples were performed.

Adverse events observed in participants with clinically significant electrocardiogram abnormalities were assessed.

The mean serum concentrations of MEDI9929 was observed at specified timepoints.

Blood samples for immunogenicity assessment included the determination of anti-drug antibodies (ADA) for MEDI9929. The number of participants with positive serum antibodies to MEDI9929 were presented.