Using the Blood Eosinophil Count to Guide Systemic Corticosteroid Treatment in Asthma Exacerbations

Study Overview
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Brief Summary
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Asthma attacks which are moderate-to-severe are typically treated with corticosteroids, but the optimal treatment duration is unknown and treatment responses can be variable. Inadequate treatment may compromise recovery, but increased exposure to corticosteroids is, in turn, associated with drug-related adverse effects. There is a need for a biomarker to guide duration of corticosteroid treatment in asthma attacks. One such candidate biomarker is the blood eosinophil count, which may predict steroid-responsiveness. We hypothesize that the blood eosinophil count can potentially be used as a biomarker to guide the duration of corticosteroids in moderate-to-severe asthma attacks. This study will recruit individuals hospitalized for asthma attack. Participants will be randomized to standard care or blood-eosinophil guided systemic corticosteroid therapy. Subjects in the standard arm will receive oral corticosteroids for a total of 5 days. Subjects in the blood-eosinophil guided arm will receive oral corticosteroids for a total of 5 days if admission eosinophil count is ≥ 0.300 x 10^3/µL, and receive 3 days of oral corticosteroids if the admission blood eosinophil is < 0.300 x 10^3/µL. The rate of treatment failure will be compared between these two groups.

Official Title
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Investigating the Blood Eosinophil Count as a Biomarker to Guide Systemic Corticosteroid Treatment in Hospitalized Exacerbations of Asthma: a Randomized, Controlled, Open-label, Noninferiority Trial

Conditions
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Asthma Attack, Asthma

Intervention / Treatment
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* Other: Standard care
* Other: Eosinophil-directed care


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 21 years old Admitted for acute exacerbation of asthma and have received ≤ 3 days of systemic corticosteroids Have a had a blood eosinophil count (as part of routine clinical care) drawn before administration of systemic corticosteroid Have not taken SCS within 7 days prior to presentation to hospital Exclusion Criteria: Concomitant pneumonia Admission to high-dependency/intensive care unit, or requirement for invasive/noninvasive mechanical ventilation Eosinophilia due to other known causes (eosinophilic granulomatosis and polyangiitis, parasitic infections, malignancy) Other concomitant respiratory conditions e.g. chronic obstructive pulmonary disease, bronchiectasis Those on anti-IL5 or anti-IL5R treatment Pregnant subjects Subjects who are already on an investigational drug or has been participating in another clinical study with an investigational product within the last 6 months Subjects deemed by investigators to have a life expectancy of < 12 months (any cause) Prisoners

Ages Eligible for Study
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Minimum Age: 21 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Standard care<br> | Other: Standard care<br>* Oral prednisolone for 5 days<br>|
| Experimental: Eosinophil-directed care<br> | Other: Eosinophil-directed care<br>* Oral prednisolone for 5 days if eosinophil count is ≥ 0.300 x 10^3/µL, or 3 days if eosinophil is < 0.300 x 10^3/µL<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Proportion of participants experiencing treatment failure | Defined as death from any cause, or need for invasive/noninvasive mechanical ventilation, or need to restart/extend systemic steroid treatment | Through the duration of the index admission for asthma attack, typically 3-5 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Length of hospital stay (number of days) |  | Through the duration of the index admission for asthma attack, typically 3-5 days | 
| Cumulative steroid dose at index admission (mg prednisolone-equivalent) |  | Through the duration of the index admission for asthma attack, typically 3-5 days | 
| Proportion of participants receiving additional systemic steroid course within 14 days |  | 14 days | 
| Asthma Control Questionnaire-5 |  | At baseline, 7, 14, 30 and 90 days | 
| Proportion of participants experiencing all-cause death |  | 30 and 90 days | 
| Proportion of participants who develop pneumonia |  | 30 and 90 days | 
| Proportion of participants who develop venous thromboembolism |  | 30 and 90 days | 
| Proportion of participants who develop sepsis |  | 30 and 90 days | 
| Proportion of participants who develop fractures |  | 30 and 90 days | 
| Proportion of participants who develop upper gastrointestinal bleeds/peptic or gastric ulcers |  | 30 and 90 days | 
| Time to next emergency department visit or admission for asthma |  | 1 year |