Asthma exacerbation was defined as a worsening of asthma that led to any of the following:

• Use of systemic corticosteroids for at least 3 days; a single depo-injectable dose of corticosteroids was considered equivalent to a 3-day course of systemic corticosteroids.
• An emergency room (ER) or urgent care (UC) visit (defined as evaluation and treatment for <24 hours in an ER or UC centre) due to asthma that required systemic corticosteroids (see above).
• An inpatient hospitalisation (defined as admission to an inpatient facility and/or evaluation and treatment in a healthcare facility for ≥24 hours) due to asthma.

AAER = number of exacerbations*365.25 / (follow-up date - date of randomisation + 1) (where maximum follow-up time for a patient was approximately 52 weeks).

AAER in the tralokinumab group was compared to that seen in the placebo group up to Week 52 using a negative binomial model; rate ratios and rate reductions are both presented for comparative statistical analyses.

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study.

Lung function was assessed by FEV1 which was measured by spirometry. Spirometry was performed by the Investigator or authorised delegate according to American Thoracic Society/European Respiratory Society guidelines. The mean percent change from baseline in pre-BD FEV1 at Week 52 is presented.

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study. Only patients with data available at the timepoints of testing were included in the analyses.

Asthma symptoms during night-time and daytime were recorded by the patient each morning and evening in the Asthma Daily Diary. Symptoms were recorded using a 4-point response scale, which ranged from 0 to 3, where 0 indicated no asthma symptoms. Asthma symptom daytime score (recorded in the evening), night-time score (recorded in the morning), and total score were calculated separately. The daily asthma symptom total score was calculated by taking the sum of the night-time and daytime asthma symptom scores recorded each day, ranging from 0 to 6. A lower symptom score indicated a better outcome. The change from baseline in bi-weekly mean daily asthma symptom total score is presented.

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study. Only patients with data available at the timepoints of testing were included in the analyses.

The AQLQ(S)+12 is a questionnaire that measures health-related quality of life for patients with asthma aged 12 and older. The questionnaire comprises 32 questions and has 4 separate domains (asthma symptoms, activity limitations, emotional function and environmental stimuli). Patients were asked to recall their experiences during the previous 2 weeks and to score each of the questions on a 7-point scale ranging from 7 (no impairment) to 1 (severe impairment). The total score was calculated as the mean response to all questions, ranging from 1 (severe impairment) to 7 (no impairment). Individual AQLQ(S)+12 total score changes of ≥0.5 were considered to be clinically meaningful. The mean change from baseline in AQLQ(S)+12 score at Week 52 is presented.

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study. Only patients with data available at the timepoints of testing were included in the analyses.

The ACQ-6 questionnaire is a shortened version of the ACQ (omitting FEV1 measurement) that assesses asthma symptoms (night-time awakenings, symptoms on waking, activity limitation, dyspnoea, wheezing) and rescue short-acting β2-agonists medication use during the past week. Questions were weighted equally and scored on a 7-point scale from 0 (totally controlled) to 6 (severely uncontrolled). The mean ACQ-6 score was the mean of the responses, ranging from 0 (totally controlled) to 6 (severely uncontrolled). Mean scores of ≤0.75 indicate well-controlled asthma, scores between 0.75 and ≤1.5 indicate partly controlled asthma and a score >1.5 indicates not well-controlled asthma. Individual changes of at least 0.5 were considered to be clinically meaningful. The mean change from baseline in ACQ-6 score at Week 52 is presented.

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study. Only patients with data available at the timepoints of testing were included in the analyses.

The annual rate of exacerbations associated with an ER/UC visit or hospitalisation up to Week 52 are presented for non-adjudicated data (i.e. events assessed by the Investigator and recorded in the electronic case report form).

AAER = number of exacerbations*365.25 / (follow-up date - date of randomisation + 1) (where maximum follow-up time for a patient was approximately 52 weeks).

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study.

The EQ-5D-5L questionnaire assesses 5 dimensions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. Each dimension has 5 response options (no problems, slight problems, moderate problems, severe problems and extreme problems) that reflect increasing levels of difficulty. The patient was asked to indicate his/her current health state by selecting the most appropriate level in each of the 5 dimensions. The questionnaire also included a VAS, where the patient was asked to rate current health status on a scale of 0 to 100, with 0 being the worst imaginable health state. The mean change from baseline in EQ-5D-5L VAS scores at Week 52 is presented.

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study. Only patients with data available at the timepoints of testing were included in the analyses.

Salbutamol, albuterol or levalbuterol were used as rescue medication during the study in the event of a worsening of asthma symptoms. Rescue medication use was measured by the bi-weekly mean number of inhalations (puffs) per day, calculated as: total morning puffs + total evening puffs + 2*(total morning nebuliser use + total evening nebuliser use)/ total number of days with data in bi-weekly period. The change from baseline in bi-weekly mean total asthma rescue medication use at Week 52 is presented.

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study. Only patients with data available at the timepoints of testing were included in the analyses.

Home PEF testing was performed by the patient using an electronic, hand-held spirometer (peak flow meter) and was performed in the morning upon awakening (prior to taking their morning asthma controller) and in the evening at bedtime (prior to taking their evening asthma controller). The mean change from baseline in home PEF values at Week 52 are presented separately for morning and evening.

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study. Only patients with data available at the timepoints of testing were included in the analyses.

The patient captured night-time awakenings (yes/no) and the use of rescue medication during these awakenings (yes/no) each morning in the Asthma Daily Diary. Night-time awakenings (percentage) was defined as the number of nights with awakenings due to asthma and requiring rescue medication divided by number of nights with data. The change from baseline in bi-weekly means (percentage) night-time awakenings due to asthma requiring rescue medication use at Week 52 is presented.

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study. Only patients with data available at the timepoints of testing were included in the analyses.

The number of patients with ≥1 asthma exacerbation up to Week 52 is presented.

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study.

The WPAI+CIQ consists of questions about how asthma and asthma-related issues impact a patient's ability to work, attend classes and perform regular daily activities. The questionnaire contains 10 questions relating to the patient's experience over the previous 7 days.

The WPAI+CIQ outcomes for productivity loss are presented separately for those currently employed and for those currently in school and are expressed as mean productivity loss (percentage) at Week 52, with higher numbers indicating less productivity.

Work Productivity Loss = {Q2/(Q2+Q4)+[(1-Q2/(Q2+Q4))x(Q5/10)]}*100 (Absenteeism = Q2/(Q2+Q4)*100; Presenteeism = (Q5/10)*100).

Class Productivity Loss = {Q7/(Q7+Q8) + [(1-Q7/(Q7+Q8))x(Q9/10)]}*100 (Absenteeism = Q7/(Q7+Q8)*100; Presenteeism = (Q9/10)*100).

Note: QX refers to response to question number X on WPAI+CIQ questionnaire.

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study. Only patients with data available at the timepoints of testing were included in the analyses.

The WPAI+CIQ consists of questions about how asthma and asthma-related issues impact a patient's ability to work, attend classes and perform regular daily activities. The questionnaire contains 10 questions relating to the patient's experience over the previous 7 days.

The WPAI+CIQ outcomes for activity impairment are presented separately for those currently employed and for those currently in school and are expressed as mean impairment percentages at Week 52, with higher numbers indicating greater impairment.

Activity impairment = (Q10/10)*100. Note: QX refers to response to question number X on WPAI+CIQ questionnaire.

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study. Only patients with data available at the timepoints of testing were included in the analyses.

Broad-based healthcare utilisation asthma-related event information was collected by the Investigator/authorised delegate at each visit. At Visit 1, healthcare resource utilisation information was collected with a 1-year recall period; subsequent visits collected information with a recall period of 'since the last scheduled visit'. Total number of times the healthcare encounter occurred was calculated across all patients for each of the following categories:

• Ambulance transport,
• Emergency room visits,
• Unscheduled outpatient visits (visit to specialist and/or visit to primary healthcare physician and/or other healthcare visit),
• Home visits (home visit, physician and/or other healthcare professional),
• Telephone calls (telephone calls to physician and/or nurse), and
• Advanced pulmonary function test.

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study.

Broad-based healthcare utilisation asthma-related event information was collected by the Investigator/authorised delegate at each visit. At Visit 1, healthcare resource utilisation information was collected with a 1-year recall period; subsequent visits collected information with a recall period of 'since the last scheduled visit'. Total number of days spent in hospital was calculated across all patients for the following healthcare encounter category:

• Hospitalisations (hospitalisations, intensive care and/or general care).

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study.

Broad-based healthcare utilisation asthma-related event information was collected by the Investigator/authorised delegate at each visit. At Visit 1, healthcare resource utilisation information was collected with a 1-year recall period; subsequent visits collected information with a recall period of 'since the last scheduled visit'. Total number of assessments was calculated across all patients for the following healthcare encounter category:

• Spirometry.

The FAS included all randomised patients with the potential to receive 52 weeks of IP and receiving any IP, irrespective of their protocol adherence and continued participation in the study.

To evaluate the pharmacokinetics (PK), pre-dose blood samples were collected at each visit and tralokinumab concentrations in serum were determined. Mean Ctrough concentrations are presented at each indicated visit up to Week 72.

All patients in the FAS who received tralokinumab and who had PK blood samples were included in the PK analysis set. Only patients in the biomarker positive and negative PK populations and with data available at the timepoints of testing were included in the analyses.

Assessments of ADA were performed using a tiered approach (screening, confirmatory and titering assays). Confirmed ADA positive samples were also tested for the presence of neutralising antibodies (nAb). ADA prevalence was defined as proportion of the study population having drug-reactive antibodies at any point in time. ADA incidence (treatment-emergent ADA) was defined as the sum of both treatment-induced (post-baseline ADA positive only) and treatment-boosted ADA. Persistently positive was defined as positive at ≥2 post-baseline assessments (with ≥16 weeks between first and last positive) or positive at last post-baseline assessment. Transiently positive was defined as having at least 1 post-baseline ADA positive assessment and not fulfilling the conditions of persistently positive. Treatment-boosted ADA was defined as baseline positive ADA titer that was boosted to a 4-fold or higher level following drug administration. Note: 'positive' is denoted by 'pos' in some category titles.

The ADA evaluable population included all patients in the safety analysis set (i.e. those who had received any IP) who had non-missing baseline ADA and at least 1 non-missing post-baseline ADA result.