Super-Sized flu shot tested for Seniors' heart and lung protection
NCT ID NCT04137887
First seen Jun 26, 2026 · Last updated Jun 26, 2026
Summary
This study compared a high-dose flu vaccine to the standard-dose shot in over 33,000 adults aged 65 and older. The goal was to see if the high-dose version could better prevent hospitalizations for heart and lung problems. The trial was terminated early, so the full picture is not available.
What this could mean
Our plain-language read of the trial. This is informational only, not medical advice or a prediction.
- Active substance
- High-dose quadrivalent influenza vaccine (Efluelda®)
- What this could lead to
- If successful, this could show that a stronger flu shot offers better protection against serious heart and lung complications in older adults.
- What could go wrong
- The trial was terminated early, so results are limited. It is unclear if the high-dose vaccine is truly superior for preventing hospitalizations.
This is an AI summary of the original study and may miss details. Read our disclaimer.
Study facts
What this study's own registry entry says, in plain language.
- Phase
-
Phase 3
Large-scale testing in a bigger group. Usually the last step before a treatment can be approved.
- Participants
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33,096 people
The number who actually took part.
- Started
-
Nov 2019
- Finished
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May 2020
- Lead sponsor
-
A company
The lead sponsor is a pharmaceutical, biotech, or medical-device company.
Who can take part
This study's own entry requirements. Only the study team can say for certain whether you qualify.
- Ages
-
65 years and older
- Sex
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Anyone
- Healthy volunteers
-
Accepted
You do not need to have the condition being studied to take part.
Show the full entry requirements Hide the full entry requirements
Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.
Inclusion criteria: \- Aged 65 years or older on the day of inclusion ("65 years" means from the day of the 65th birthday). Exclusion criteria: * Participation at the time of study enrollment (or in the 4 weeks \[28 days\] preceding the study vaccination) or planned participation during the present study period in another clinical study investigating a vaccine, drug, medical device, or medical procedure. * Previous vaccination against influenza (in the preceding 6 months) with either the study vaccines or another vaccine. * Known systemic hypersensitivity to any of the vaccine components, or history of a life-threatening reaction to the vaccines used in the study or to a vaccine containing any of the same substances. The above information was not intended to contain all considerations relevant to a participant's potential participation in a clinical trial.
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Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Locations
-
Investigational Site Number 2469999
Tampere, 33520, Finland
More trials for these conditions
Other studies related to the condition(s) this trial covers.
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