A Study to Investigate the Efficacy and Safety of Tezepelumab Compared With Placebo in Children 5 to < 12 Years Old With Severe Asthma

Inclusion Criteria

• •1. Written informed consent from (ICF) at least one parent/caregiver (as per local guidelines) and accompanying informed assent from the participant (where the participant is able to provide assent) prior to admission to the study.
• •2. Participants must be 5 to \< 12 years of age, at the time of signing the assent form (as applicable per local guidelines) and their caregivers signing the ICF and at Visit 3.
• •3. Documented physician diagnosis of severe asthma confirmed and evaluated for at least 6 months prior to Visit 1.
• •4. Documented physician-prescribed treatment with a total daily dose of either medium or high dose, for at least 3 months with stable dose ≥ 1 month prior to Visit 1.
• •5. Documented treatment with at least one additional maintenance asthma controller medication is required according to local guidelines and standard of care; (long-acting beta agonist, leukotriene receptor antagonist, long-acting muscarinic antagonist) for at least 3 months with stable dose ≥ 1 month prior to Visit 1.
• •6. Supportive evidence of asthma as documented by one of the following:
• •1. Post-BD (albuterol/salbutamol) responsiveness of FEV1 ≥ 10% during Screening (15 to 30 min after administration of 4 puffs of albuterol/salbutamol with a maximum of 12 puffs of reliever medication only if tolerated by the participant) at either Visit 1 or Visit 2.
• •If (a) is not achieved at Visit 1 or Visit 2, historical documentation by any of the below prior to Visit 1:
• •2. Post-BD responsiveness of FEV1 ≥ 10%.
• •3. Positive methacholine challenge defined as provocative concentration (PC20) of ≤ 16 mg/mL.
• •4. PEF average daily diurnal variability \> 13% over a 2-week period.
• •5. Variability of FEV1 ≥ 12% between any two clinical visits.
• •6. Positive exercise challenge test (defined as a fall in FEV1 of \> 12%).
• •7. FeNO ≥ 20 ppb despite confirmed ICS maintenance therapy.
• •7. History of at least 2 severe asthma exacerbation events OR 1 severe asthma exacerbation event resulting in hospitalisation within 12 months prior to Visit 1.
• •8. Pre-BD FEV1 \>50% and ≤ 95%PN OR FEV1/forced vital capacity (FVC) ratio ≤ 0.85 at either Visit 1 or Visit 2.
• •9. Evidence of uncontrolled asthma, with at least 1 of the below criteria:
• •1. ACQ-IA score ≥ 1.5 at least once during Screening/Run-in, including Visit 3 (prior to Randomisation) for participants ≥ 6 years old at Screening.
• •2. Use of reliever medication, other than as a preventive for exercise induced bronchospasm, on 3 or more days per week for at least 1 week during the Screening/Run-in period.
• •3. Sleep awakening due to asthma symptoms requiring use of reliever medication at least once during the Screening/Run-in period.
• •4. Asthma symptoms 3 or more days per week in at least 1 week during the Screening/Run-in period.
• •10. Body weight ≥ 16 kg at Visit 1 (Screening) and Visit 3 (Randomisation).