An Open-Label Extension Study of GSK3511294 (Depemokimab) in Participants Who Were Previously Enrolled in 206713 (NCT04719832) or 213744 (NCT04718103)

Primary Outcome Measures

1. Number of Participants With Any Adverse Events (AEs) and Serious AEs (SAEs)
   An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of a study intervention, whether or not considered related to the study intervention. An SAE is any untoward medical occurrence that, at any dose: results in death, is life-threatening, requires inpatient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect or any other situation according to medical or scientific judgment.
2. Number of Participants With Worst Case Post-Baseline Positive Anti-GSK3511294 Antibodies (ADA)
   Serum samples were collected for the determination of anti-GSK3511294 antibodies (ADA) using a validated electro-chemiluminescent immunoassay. The assay involved screening, confirmation and titration assays. If serum samples tested positive in the screening assay, they were considered 'potentially positive' and were further analyzed for specificity using the confirmation assay. Samples that confirmed positive in the confirmation assay were reported as 'positive'. Confirmed positive ADA samples were further characterized in the titration assay to quasi-quantitate the amount of ADA in the sample and were also further characterized in the Neutralizing antibody (Nab) assay. A participant was considered positive ADA if they had at least one positive worst case post-Baseline ADA result. Number of participants with worst case post-Baseline positive anti-GSK3511294 antibodies are presented.
3. Number of Participants With Worst Case Post-Baseline Positive Neutralizing Antibodies
   Blood samples were collected for the determination of positive neutralizing antibodies. Neutralizing antibody (NAb) test was only carried out on samples that were positive in the confirmatory binding antibody assay. A participant was considered positive for NAb if they had at least one positive worst case post-Baseline neutralizing antibody result. Number of participants with worst case post-Baseline positive neutralizing antibodies are presented.

Secondary Outcome Measures

1. Annualized Rate of Clinically Significant Exacerbations
   Clinically significant exacerbations recorded were defined as worsening of asthma requiring the use of systemic corticosteroids (CS) (such as intramuscular \[IM\], intravenous \[IV\] or oral) and/or hospitalization and/or Emergency Department (ED) visit. For all participants, IV or oral steroids (e.g., prednisone) for at least 3 days or a single IM corticosteroid dose is required. For participants on maintenance systemic corticosteroids, at least double the existing maintenance dose for at least 3 days is required. Exacerbations recorded in the electronic case report form (eCRF) were considered as verified clinically significant exacerbations and included in the analysis. Exacerbations separated by less than 7 days was treated as a continuation of the same exacerbation.
2. Change From Baseline in Asthma Control Questionnaire-5 (ACQ-5) Score
   The ACQ-5 is a five-item questionnaire developed as a measure of participants asthma symptom control. The questions are designed to be self-completed by the participant. The 5 questions enquired to recall how their asthma had been during the previous week and to respond about the frequency and/or severity of symptoms (nocturnal awakening, waking in the morning, activity limitation, shortness of breath and wheezing). The overall ACQ-5 response option is the mean score of all 5 questions representing 0 with no impairment/limitation and 6 as total impairment/ limitation. Higher scores indicated more limitations and lower score with better asthma control. Baseline was the value at Day 1 of the study. Change from Baseline was defined as value at the indicated time point minus Baseline value. Number of participants with analyzable data for one or more timepoints.
3. Change From Baseline in St. George's Respiratory Questionnaire (SGRQ) Total Score at Weeks 26 and 52
   The SGRQ is a 50-item patient-reported outcome tool used to measure Quality of Life in participants with airway obstruction diseases. The questions are designed to be self-completed by the participant. The total score was calculated by the symptom score, activity and impact score; and summarizing the impact of the disease on overall health status on 0-100 rating scale. Scores are expressed as a percentage of overall impairment where 100 representing worst possible health status and 0 indicating best possible health status. Higher scores indicating greater impairment of quality of life. Baseline was the value at Day 1 of the study. Change from Baseline was defined as value at the indicated time point minus Baseline value. Number of participants with analyzable data for one or more timepoints.
4. Change From Baseline in Pre-Bronchodilator Forced Expiratory Volume in One Second (FEV1) at Weeks 26 and 52
   Forced Expiratory Volume in One Second (FEV1) is a measure of lung function and defined as the volume of air that can be forced out in one second after taking a deep breath. FEV1 was measured electronically by spirometry. Baseline was the value at Day 1 of the study. Change from Baseline in pre-bronchodilator FEV1 was defined as value at the indicated time point minus Baseline value. Number of participants with analyzable data for one or more timepoints.