MEDI3506

Assessments related to AEs include: Occurrence/frequency, Relationship to IMP as assessed by Investigator, Intensity, Seriousness, Death, AEs leading to discontinuation of IMP, Other significant AEs. Medically significant abnormal laboratory results will be reported as AEs.

The primary endpoint will be assessed in the primary population (former smokers with symptomatic COPD and a history of exacerbations, on optimised treatment with maintenance inhaled therapy \[triple therapy, or dual therapy if triple is not considered appropriate\]).

The primary efficacy endpoint is the rate of severe COPD exacerbations.

To evaluate the effect of tozorakimab versus placebo as an add on to Standard of Care (SoC) in participants with viral lung infection requiring supplemental oxygen on the prevention of death or progression to IMV/ECMO.

The difference in mean change from baseline in FEV1

The rate ratio of severe asthma exacerbations will be assessed in the participants with uncontrolled moderate-to-severe asthma and ≥ 1 severe exacerbation within 12 months prior to screening.

In-clinic spirometry measurements were taken prior to the administration of bronchodilators. Baseline was the last measurement prior to first injection of investigational product (IP). The least squares (LS) means, LS mean differences and 80% confidence intervals (CIs), and one-sided p-value results were based on a mixed model repeated measures (MMRM). The model included fixed effects for baseline, background medication, geographic region, baseline inhaled corticosteroids (ICS) total daily dose, visit, treatment, and the baseline by visit and treatment by visit interactions. Visits within participant were considered as repeated measurements.

The EASI evaluates 4 anatomic regions for severity and extent of key disease signs and focuses on the acute and chronic signs of inflammation (ie, erythema, edema, papulation, excoriation, and lichenification). The maximum score is 72, with higher values indicating more severe disease. Analysis was performed using mixed effect model for repeated measures and MCP-mod dose response model.

UACR values are collected as triplicates at baseline and at each CSP planned visit. For each triplicate, the UACR are averaged with geometric mean. Baseline is defined as the geometric mean of UACR measurements prior to first dose of study treatment. For the intercurrent events, if a subject is lost to follow-up (EOT), discontinues treatment due to AE, or uses prohibited medication, the UACR data are treated as missing on or after the event and no imputation is performed. The LS means of percent change and difference in percent change, corresponding 90% confidence intervals are calculated based on a mixed model with repeated measures (MMRM) of log (UACR post-baseline/UACR baseline) as the response, adjusting for fixed effects of treatment, visit, and treatment-by-visit interaction, SGLT2i, region (Japan or ROW), baseline log UACR, and baseline log UACR-by-visit interaction. The MMRM includes UACR values at protocol specified visits from baseline up to Day 169.

An adverse event (AE) is any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. A serious adverse event (SAE) is an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly. The 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. An adverse event of special interest (AESI) was defined as any serious or nonserious event of scientific and medical interest specific to understand the study drug.

Number of participants with Grade 2 or more toxicity grades reported in laboratory parameters are reported. Abnormal clinical laboratory parameters defined as any abnormal finding during analysis of hematology and serum chemistry.

Change from baseline in blood pressure at Day 169 in Part 1, Part 2, and Part 3 are reported.

Change from baseline in pulse rate at Day 169 in Part 1, Part 2, and Part 3 is reported.

Change from baseline in respiratory rate at Day 169 in Part 1, Part 2, and Part 3 are reported.

Change from baseline in body temperature at Day 169 in Part 1, Part 2, and Part 3 are reported.

Number of participants with change from basleine in QTcF in Part 1, Part 2, and Part 3 are reported. The change from baseline in QTcF at Day 169 data are reported in 3 categories as: \<= 30 msec, \> 30 to \<= 60 msec, and \> 60 msec.