B Cell and Antibody Response to Seasonal Influenza Vaccines in Younger and Older Adults

May 11, 2026 updated by: James Kobie, University of Alabama at Birmingham
This study will examine how various FDA-approved seasonal influenza vaccine types, used in a manner consistent with their approved use, impact the characteristics of influenza specific antibodies in humans, and how these responses differ based on age and prior immunization history.

Study Overview

Status

Active, not recruiting

Conditions

Detailed Description

This study is particularly focused on studying antibodies, a protein in blood that react with foreign substances (such as bacteria and viruses) to help eliminate them. This study will examine antibodies and the cells that they are produced by, B cells that develop in response to the influenza vaccine.

The majority of antibodies that develop following seasonal influenza vaccine are highly specific for particular influenza strain that comprises the influenza vaccine, necessitating the annual reformulation of the influenza vaccine to match strains expected to be in circulation for the upcoming season. This is problematic, and strategies to develop an influenza vaccine that can promote the robust and persistent development of antibodies that are effective against a wide range of influenza strains are needed. One potential strategy is to promote antibody responses targeting the neuraminidase (NA) protein of influenza. NA is more highly conserved across influenza viruses as compared to the hemagglutinin (HA) protein which is the major component of the influenza vaccine. Thus understanding how differences in seasonal influenza vaccines may influence the quality and breadth of HA and NA specific antibodies is of importance in the development of more effective influenza vaccines.

There are several FDA-approved seasonal inactivated influenza vaccines (IIVs) and it remains unknown the extent to which they may induce HA and NA-specific B cells and antibodies, and particularly those that may have broad protective activity against influenza. Differences in the various seasonal IIVs, such as how they were produced, their dose, and the immune stimulating components (adjuvant) they contain may influence the HA and NA-specific response. The two major types of seasonal IIV approved for adults are IIV that is comprised of inactivated influenza virus that was grown in chicken eggs (e.g. Sanofi Fluzone, IIV), and the other comprised of inactivated influenza virus that was grown in cell culture (e.g. Seqirus Flucelvax, cc-IIV). Additionally, for adults 65 years and older, High Dose Fluzone (HD-IIV3), and Sequris Fluad IIV, which includes an adjuvant (a-IIV3). This study will evaluate the relative induction of HA and NA-specific antibodies and B cells from adults immunized with these various seasonal influenza vaccines, and how these responses may change after each year, and differ in older adults who may have a different past exposure history to influenza compared to younger adults. The seasonal influenza vaccines will be given as standard of care, in populations they are approved for, and administered in approved dose and route.

Study Type

Interventional

Enrollment (Estimated)

50

Phase

  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Alabama
      • Birmingham, Alabama, United States, 35294
        • University of Alabama at Birmingham

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 80 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • 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 Criteria:

  • 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:

    1. History of Guillain-Barre Syndrome
    2. History of egg allergy
    3. History of gelatin allergy
    4. History of moderate to severe illness with or without fever within 6 weeks of receipt of influenza vaccine
  • 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:

    1. No recent respiratory infections in the past 4 weeks at time of vaccination
    2. Malignancy
    3. Evidence of Inflammation: Systemic Lupus Erythematosis, Rheumatoid Arthritis, Polymyositis, Dermatomyositis, Scleroderma, Crohn's Disease, Ulcerative Colitis.
    4. Lymphoproliferative Disorder
    5. Known Immunodeficiency
    6. Myocardial Infarction <6 months
    7. Cerebral Vascular Accident
    8. Peripheral Vascular Disease- recannulation <6months
    9. Cardiac Insufficiency - congestive heart failure
    10. Hypertension with increased blood urea nitrogen (BUN)
    11. Renal Failure
    12. Dementia
    13. Alcoholism (defined as >17 drinks/week)
    14. Drug Abuse (excluding marijuana)
    15. HIV positive
    16. History of hepatitis
    17. History of immunization within 4 weeks of study participation or plan to receive non- IIV vaccination within 4 weeks of receiving IIV
    18. Moderate to severe illness at time of enrollment
  • 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.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Fluzone Younger
10 adults 18-50 years old, will receive a single dose of the Fluzone influenza vaccine each year for two sequential years
inactivated seasonal influenza vaccine
Other Names:
  • influenza vaccine
Active Comparator: Flucelvax
10 adults 18-50 years old, will receive a single dose of the Flucelvax influenza vaccine each year for two sequential years
inactivated seasonal influenza vaccine
Other Names:
  • influenza vaccine
Active Comparator: Fluzone Older
10 adults 65-80 years old, will receive a single dose of the Fluzone influenza vaccine
inactivated seasonal influenza vaccine
Other Names:
  • influenza vaccine
Active Comparator: Fluzone High Dose
10 adults 65-80 years old, will receive a single dose of the Fluzone High-Dose influenza vaccine
inactivated seasonal influenza vaccine
Other Names:
  • high dose influenza vaccine
Active Comparator: Fluad
10 adults 65-80 years old, will receive a single dose of the Fluad influenza vaccine
inactivated seasonal influenza vaccine
Other Names:
  • adjuvanted influenza vaccine

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Hemagglutinin antibody
Time Frame: 3 months after vaccination
hemagglutinin plasma antibody titer
3 months after vaccination
Neuraminidase antibody
Time Frame: 3 months after vaccination
Neuraminidase plasma antibody titer
3 months after vaccination

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Hemagglutinin Memory B cell ELISPOT Response
Time Frame: 3 months after vaccination
hemagglutinin-specific memory B cells
3 months after vaccination
Neuraminidase Memory B cell ELISPOT Response
Time Frame: 3 months after vaccination
Neuraminidase-specific memory B cells
3 months after vaccination

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: James J Kobie, PhD, University of Alabama at Birmingham

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

April 1, 2021

Primary Completion (Actual)

May 11, 2026

Study Completion (Estimated)

May 1, 2027

Study Registration Dates

First Submitted

September 22, 2019

First Submitted That Met QC Criteria

September 22, 2019

First Posted (Actual)

September 24, 2019

Study Record Updates

Last Update Posted (Actual)

May 14, 2026

Last Update Submitted That Met QC Criteria

May 11, 2026

Last Verified

May 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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