Influenza
Conditions
Keywords
Influenza, Vaccination, Pragmatic, Registry, Pneumonia, Respiratory, Cardiovascular, Meta-analysis
Brief summary
This prespecified analysis will pool the datasets from two pragmatic randomized trials evaluating the relative vaccine effectiveness of high-dose vs. standard-dose influenza vaccine against severe clinical outcomes: the DANFLU-2 (A Pragmatic Randomized Trial to Evaluate the Effectiveness of High-Dose Quadrivalent Influenza Vaccine vs. Standard-Dose Quadrivalent Influenza Vaccine in Older Adults) trial and the GALFLU (Pragmatic Randomized Trial to Evaluate the Effectiveness of High-Dose Quadrivalent Influenza Vaccine vs. Standard-Dose Quadrivalent Influenza Vaccine in Adults Aged 65 to 79 Years in Galicia, Spain) trial. The purpose of the pooled analysis is to ensure adequate statistical power for evaluating relative vaccine effectiveness against severe clinical outcomes and to increase generalizability of the results by combining data from two countries.
Interventions
BIOLOGICALHigh-Dose Influenza Vaccine
For this arm, the high-dose quadrivalent influenza vaccine Efluelda®/Fluzone® High-Dose Quadrivalent will be used.
BIOLOGICALStandard-Dose Influenza Vaccine
Any standard-dose quadrivalent influenza vaccine administered in the governmental influenza vaccine programs may be used.
Sponsors
Sanofi
Hospital Clinico Universitario de Santiago
Tor Biering-Sørensen
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
65 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Pragmatic trials conducted to estimate the relative vaccine effectiveness of high-dose influenza vaccine compared with standard-dose influenza vaccine using the DANFLU-2 protocol or a protocol developed based on the DANFLU-2 protocol
Exclusion criteria
* Low data quality * Influenza circulation threshold was not met in any of the study seasons * Severe under-enrollment in all seasons
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Hospitalization for influenza or pneumonia | ≥14 days after vaccination up to 8 months |
Secondary
| Measure | Time frame |
|---|---|
| Laboratory-confirmed influenza hospitalization | ≥14 days after vaccination up to 8 months |
| All-cause hospitalization | ≥14 days after vaccination up to 8 months |
| Hospitalization for any cardio-respiratory disease | ≥14 days after vaccination up to 8 months |
| Hospitalization for influenza | ≥14 days after vaccination up to 8 months |
| Hospitalization for pneumonia | ≥14 days after vaccination up to 8 months |
| All-cause mortality | ≥14 days after vaccination up to 8 months |
Other
| Measure | Time frame |
|---|---|
| Hospitalization for myocardial infarction | ≥14 days after vaccination up to 8 months |
| Hospitalization for heart failure | ≥14 days after vaccination up to 8 months |
| Major adverse cardiovascular events (MACE) defined as a composite of hospitalization for acute myocardial infarction, hospitalization for stroke, and cardiovascular death | ≥14 days after vaccination up to 8 months |
| MACE defined as a composite of hospitalization for acute myocardial infarction, hospitalization for stroke, hospitalization for heart failure, and cardiovascular death (alternate definition #1) | ≥14 days after vaccination up to 8 months |
| MACE defined as a composite of hospitalization for acute myocardial infarction, hospitalization for stroke, and all-cause death (alternate definition #2) | ≥14 days after vaccination up to 8 months |
| Hospitalization requiring mechanical ventilation | ≥14 days after vaccination up to 8 months |
| Laboratory-confirmed influenza | ≥14 days after vaccination up to 8 months |
| Laboratory-confirmed pneumococcal pneumonia | ≥14 days after vaccination up to 8 months |
| Laboratory-confirmed COVID-19 | ≥14 days after vaccination up to 8 months |
| Cardio-respiratory mortality | ≥14 days after vaccination up to 8 months |
| Respiratory mortality | ≥14 days after vaccination up to 8 months |
| Cardiovascular mortality | ≥14 days after vaccination up to 8 months |
| In-hospital mortality | ≥14 days after vaccination up to 8 months |
| Intensive care unit admission | ≥14 days after vaccination up to 8 months |
| Any hospital contact associated with laboratory-confirmed influenza | ≥14 days after vaccination up to 8 months |
| Any exacerbation of pre-existing chronic obstructive pulmonary disease | ≥14 days after vaccination up to 8 months |
| Any exacerbation of pre-existing chronic obstructive pulmonary disease (alternate definition) | ≥14 days after vaccination up to 8 months |
| Severe exacerbation of pre-existing chronic obstructive pulmonary disease | ≥14 days after vaccination up to 8 months |
| Severe exacerbation of pre-existing chronic obstructive pulmonary disease (alternate definition) | ≥14 days after vaccination up to 8 months |
| Hospitalization for atrial fibrillation | ≥14 days after vaccination up to 8 months |
| Any exacerbation of pre-existing asthma (alternate definition) | ≥14 days after vaccination up to 8 months |
| Severe exacerbation of pre-existing asthma | ≥14 days after vaccination up to 8 months |
| Severe exacerbation of pre-existing asthma (alternate definition) | ≥14 days after vaccination up to 8 months |
| Exacerbation of pre-existing heart failure | ≥14 days after vaccination up to 8 months |
| Exacerbation of pre-existing heart failure (alternate definition) | ≥14 days after vaccination up to 8 months |
| Hospitalization for pericarditis | ≥14 days after vaccination up to 8 months |
| Hospitalization for myocarditis | ≥14 days after vaccination up to 8 months |
| New-onset dementia | ≥14 days after vaccination up to 8 months |
| Any exacerbation of pre-existing asthma | ≥14 days after vaccination up to 8 months |
| Hospitalization for stroke | ≥14 days after vaccination up to 8 months |
| Hospitalization for influenza or pneumonia (alternate definition) | ≥14 days after vaccination up to 8 months |
| Hospitalization for pneumonia (alternate definition) | ≥14 days after vaccination up to 8 months |
| Hospitalization for influenza (alternate definition) | ≥14 days after vaccination up to 8 months |
| Hospitalization for any respiratory disease | ≥14 days after vaccination up to 8 months |
| Hospitalization for any cardiovascular disease | ≥14 days after vaccination up to 8 months |
Countries
Denmark
Outcome results
None listed