Vaccination Against Influenza to Prevent Cardiovascular Events After Acute Coronary Syndromes

Study Overview
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Brief Summary
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Cardiovascular disease has a great burden in the context of public health, as well as the low pharmacological adherence of patients who have chronic non-transmissible diseases. However, the investigators do not have data on the efficacy of vaccination to reduce cardiovascular events in the acute coronary syndromes, and the few studies evaluating the cardioprotective potential of the influenza vaccine were conducted in countries with well defined seasonalities, divergent of Brazil, that presents a constant viral circulation during all months of the year and distinct among its regions. Therefore, study evaluating higher dose vaccination in a period that contemplates the seasonality of the influenza virus in Brazil may bring important findings to different scientific gaps, as well as clarify questions about the possible benefit of doubled vaccination - which does not present contraindications - immediately after a atherothrombotic event. If it shows real benefit, it could also be a future therapeutic tool adjuvant to traditional drug therapy in the prevention of cardiovascular events.

Detailed Description
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Phase III, randomized, controlled, multicenter, open-label, superiority, 1:1 allocation, blind assessment of clinical outcomes and intention-to-treat analysis clinical trial to determine whether increased doses(double dose) of influenza vaccine in the hospital phase, when compared to usual dose vaccination (30 days of randomization), decreases the risk of cardiovascular and respiratory events. Hospitalizations due to COVID-19 are excluded from the respiratory infection component of the primary outcome.

Official Title
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Evaluation of the Effectiveness of Double Dose Influenza Vaccination to Reduce Major Cardiovascular Events After an Acute Coronary Syndrome

Conditions
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Acute Coronary Syndrome

Intervention / Treatment
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* Biological: Double Dose Quadrivalent Influenza Vaccine
* Biological: Standard Dose Quadrivalent Influenza Vaccine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria Age >= 18 years and older Acute coronary syndrome in hospital phase. Exclusion Criteria: Participation in another clinical trial with vaccines; Refusal to provide consent; Hypersensitivity and/or anaphylaxis to any component of the vaccine, or Guillain-Barré within 6 weeks after previous influenza vaccine; Have already received the influenza vaccine with the same strains used in the study within the last 12 months of inclusion in the study Breastfeeding women; Pregnant women; Presenting an acute coronary syndrome during months of December, January, and February. Acute coronary syndrome hospitalization >7 days

Ages Eligible for Study
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Minimum Age: 18 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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Double Dose Quadrivalent Influenza Vaccine<br>Double Dose QIV during index ACS hospitalization | Biological: Double Dose Quadrivalent Influenza Vaccine<br>* Double Dose QIV (30µg Hemagglutinin)<br>|
| Active Comparator: Standard Dose Quadrivalent Influenza Vaccine<br>Standard Dose QIV 30 days after randomization | Biological: Standard Dose Quadrivalent Influenza Vaccine<br>* Standard Dose QIV (15µg Hemagglutinin)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hierarchical composite endpoint consisting of death, myocardial infarction, stroke, unstable angina hospitalization, heart failure hospitalization, urgent coronary revascularization or respiratory infections hospitalizations | The primary objective will be analyzed using the win ratio approach comparing every participant of treatment group to every participant of control group to determine a winner | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Key Secondary End Point is a hierarchical outcome consisting only of cardiovascular death, myocardial infarction or stroke. | The key secondary end point will be analyzed using the win ratio approach comparing every participant of treatment group to every participant of control group to determine a winner | 12 months | 
| Total mortality | Time to first occurrence of all cause death | 12 months | 
| Cardiovascular mortality | Time to first occurrence of CV death | 12 months | 
| Myocardial infarction | Time to first occurrence of myocardial infarction | 12 months | 
| Unstable angina hospitalization | Time to first occurrence of Unstable angina hospitalization | 12 months | 
| Stroke | Time to first occurrence of stroke | 12 months | 
| TIA (Transient ischemic attack) | Time to first occurrence of TIA | 12 months | 
| Heart failure hospitalizations | Time to first occurrence of Heart failure hospitalizations | 12 months | 
| Respiratory infections hospitalizations | Time to first occurrence of hospitalization due to upper and lower respiratory tract infection (excluding COVID-19) | 12 months | 
| Need for myocardial revascularization | Time to first occurrence of urgent coronary revascularization ischemia guide (urgent or not-urgent) | 12 months | 
| Stent thrombosis | Time to first occurrence of probable and definite stent thrombosis | 12 months | 
| COVID-19 hospitalizations | Time to first occurrence of COVID-19 hospitalizations | 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Unstable angina, Non-ST-Elevation Myocardial Infarction - NSTEMI, ST-Elevation Myocardial Infarction - STEMI, Quadrivalent Influenza Vaccine - QIV