NCT06023589 · AstraZeneca
A Study to Investigate the Efficacy and Safety of Tezepelumab Compared With Placebo in Children 5 to < 12 Years Old With Severe Asthma
(HORIZON)
What this study is about
To assess the effectiveness and safety of tezepelumab in pediatric participants with severe uncontrolled asthma on medium to high-dose inhaled corticosteroids (ICS) and at least one additional asthma controller medication with or without taken by mouth corticosteroids.
View original scientific description
To assess the efficacy and safety of tezepelumab in pediatric participants with severe uncontrolled asthma on medium to high-dose inhaled corticosteroids (ICS) and at least one additional asthma controller medication with or without oral corticosteroids.
Interventions
BIOLOGICAL
Tezepelumab
Participants will be receiving subcutaneous injection of tezepelumab
OTHER
Placebo
Participants will be receiving subcutaneous injection of matching placebo
Primary outcome measures
Annualized severe asthma exacerbation rate (AAER)
Time frame: From Baseline to Week 52
To assess the effect of tezepelumab on severe asthma exacerbations in children 5 to \< 12 years old with severe uncontrolled asthma compared with placebo.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- 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 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
Where
- Montgomery, Alabama
- Phoenix, Arizona
- Little Rock, Arkansas
- La Jolla, California
- Long Beach, California
- Orange, California
- San Diego, California
- Atlanta, Georgia
- Savannah, Georgia
- Baltimore, Maryland
- Boston, Massachusetts
- Ann Arbor, Michigan
And 17 more locations — see the full list below.
Collaborators
Amgen
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 26, 2026 · Source of record for eligibility and locations