NCT04101838
B Cell and Antibody Response to Seasonal Influenza Vaccines in Younger and Older Adults
Active, Not Recruiting
PHASE4Ages 18–80InterventionalBasic scienceUniversity of Alabama at BirminghamInvestigator-initiated
~50 participants
Updated 2026-05-14 on ClinicalTrials.gov
What's tested:FluzoneFlucelvaxFluzone High-DoseFluad
At a glance
Recruiting sites
0 of 1 listed site is recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
Hemagglutinin antibody
Measured over 3 months after vaccination
+1 more outcome measured
Conditions
Where it's being run
1 sites across 1 statesAlabama1
Study leadership
- James J Kobie, PhD · PRINCIPAL_INVESTIGATOR · University of Alabama at Birmingham
Who to contact
This trial hasn't published a contact. View it on ClinicalTrials.gov
Do you actually qualify for this trial?
Add a private profile and we'll compare every criterion below against your situation — and tell you which ones are met, uncertain, or excluding.
Eligibility criteria
Inclusion
Participation in ancillary clinical research study
Able to give informed consent
Age 18-50 years old for Arm 1 and Arm 2
Age 65-80 years old for Arm 3, Arm 4, and Arm 5
Weight of at least 110 lbs as determined by self-reporting
Exclusion
Inability to give informed consent
Refusal or inability to have blood drawn or participate in study procedures
Previous adverse reaction to influenza vaccine or medical history contraindicated for receiving influenza vaccine, including but not limited to:
Previous receipt of influenza vaccine outside of study within current season
Bleeding disorder diagnosed by a doctor (eg, factor deficiency, coagulopathy, or platelet disorder requiring special precautions)
Participant has any medical, psychiatric, or social condition, or occupational or other responsibility that, in the judgement of the investigator would interfere with, or serve as a contraindication to the planned procedure(s).
These following criteria are used for scientific reasons, and not safety reasons. Specifically, the criteria are used to obtain a population that is healthy and less likely to have conditions that may influence the immune system:
Donations of blood in the 8 weeks prior to enrollment which, combined with expected volumes to be drawn for this study, would exceed 450 mL in an 8 week period.
Current pregnancy at time of enrollment or pregnancy within last 4 months
Active or planned breastfeeding during study participation
Psychiatric condition that precludes compliance with the protocol. Specifically excluded are persons with psychoses within the past 3 years, ongoing risk for suicide, or history of suicide attempt or gesture within the past 3 years.
What this trial measures
- Hemagglutinin antibody3 months after vaccination
hemagglutinin plasma antibody titer
- Neuraminidase antibody3 months after vaccination
Neuraminidase plasma antibody titer