Immunogenicity of Influenza Vaccinations (NCT06518577) | Clinical Trial Compass
CompletedPhase 4
Immunogenicity of Influenza Vaccinations
United States606 participantsStarted 2024-09-09
Plain-language summary
This study is a randomized immunogenicity study in an enrolled cohort with active surveillance for influenza-like illness (ILI). During this study, participants will be randomly assigned to receive an approved cell culture-based influenza vaccine (Flucelvax®) versus a licensed comparator influenza vaccine (Flublok®). Blood samples from participants will be collected for measurement of biomarkers of immune response at baseline (visit 1; day 1), post-vaccination (visit 2; day 29), and post-season (visit 3; day 181). Participants will be asked if they wish to also provide saliva specimens at baseline (visit 1; day 1), post-vaccination (visit 2; day 29), and post-season (visit 3; day 181). Serum and peripheral blood mononuclear cells (PBMC) and plasma samples will be isolated from whole blood and tested for biomarkers of vaccine immunogenicity, and duration of antibody responses.
Participants will receive electronic surveys via email or text message weekly asking about changes in health status and new ILI symptoms; those reporting illness may be asked to provide a respiratory swab for laboratory testing for influenza and other respiratory viruses and up to 2 additional blood draws (acute \[\<10 days after symptom onset\] and convalescent \[28 days after acute visit if lab-confirmed positive for influenza\]).
Who can participate
Age range
18 Years – 64 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Adults aged 18-64 years that have not received the current season's influenza vaccine
. English literate
. Email or text message capability for weekly follow-up
. Intention of receiving influenza vaccine based on ACIP-CDC guidelines
. Willing to provide written/electronic informed consent
. Intention of being available for entire study period and able to complete all relevant study procedures, including follow-up phone calls and clinic visits
Exclusion criteria
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Percent of Participants With a Seroprotective HAI Titer (≥1:40)
Timeframe: Visit 2 (Days 28-42, Post-vaccination)
2
The Geometric Mean Titer (GMT) of HAI Antibody
Timeframe: Up to Visit 2 (Days 28-42, Post-vaccination)
3
Percent of Participants Demonstrating Seroconversion From Baseline
Timeframe: Day 29 post-vaccination assessment (Visit 2; scheduled for Day 29 with an allowable window of Days 28-42 post-vaccination)
4
Geometric Mean Fold Rise (GMFR) in HAI Titer From Baseline
Timeframe: Day 29 post-vaccination assessment (Visit 2; scheduled for Day 29 with an allowable window of Days 28-42 post-vaccination)
. Receipt of the current season's influenza vaccine (receipt after July 1, 2024)
. History of severe allergic reaction after a previous dose of any influenza vaccine or to an influenza vaccine component
. Receipt of any licensed or investigational live vaccine within 6 weeks or non-live vaccine within 2 weeks prior to enrollment in this study or planning receipt of any vaccines between visits 1 and 2 of the study (approximately within 4 weeks after the receipt of study-administered vaccine)
. History of Guillain-Barré syndrome
. Currently pregnant, planning to become pregnant within the first three months of the study per participant self-report
. Bleeding diathesis or condition associated with prolonged bleeding that would, in the opinion of the investigator, contraindicate intramuscular injection.
. Any condition which, in the opinion of the investigators, may pose a health risk to the participant or interfere with the evaluation of the study objectives