Observing immune responses to COVID-19 vaccines in different age groups

A Clinical Observational Study of SARS-CoV-2 Specific CD8 T-Cell Responses to COVID-19 Vaccines in Humans

Observational National Institutes of Health Clinical Center (CC) · NCT04852289

This study is testing how well COVID-19 vaccines work in young and older adults by looking at their immune responses over five years.

Quick facts

Study typeObservational
Enrollment160 (estimated)
Ages18 Years and up
SexAll
SponsorNational Institutes of Health Clinical Center (CC) NIH
Drugs / interventionschemotherapy, radiation
Locations2 sites (Baltimore, Maryland and 1 other locations)
Trial IDNCT04852289 on ClinicalTrials.gov

What this trial studies

This observational study aims to compare the immune responses of young and older healthy adults after receiving COVID-19 vaccines from Pfizer or Moderna. Participants, aged 18 and older, will be screened and monitored over a five-year period to assess the presence and longevity of SARS-CoV-2 specific CD8 T cells in their blood. The study will analyze how age and sex may influence these immune responses, providing insights into cellular immunity against COVID-19. Participants will not receive the vaccine through the study but must get vaccinated at an authorized location.

Who should consider this trial

Good fit: Ideal candidates are healthy adults aged 18 and older who have not previously contracted COVID-19 and are planning to receive their first vaccine dose soon.

Not a fit: Patients who have already contracted COVID-19 or those who are unable to comply with study procedures may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could enhance understanding of how age affects immune responses to COVID-19 vaccines, potentially guiding vaccination strategies.

How similar studies have performed: Other studies have shown promising results in understanding immune responses to vaccines, making this approach both relevant and potentially impactful.

Eligibility criteria

Show full inclusion / exclusion criteria
* INCLUSION CRITERIA:

In order to be eligible to participate in this study, an individual must meet all of the following criteria:

* Ability of subject to understand the study and stated willingness to comply with all study procedures and availability for the duration of the study.
* Male or female aged 18 years or older.
* Able to speak and read English.
* Willingness and ability to come to the NIH/National Institute on Aging Clinical Research Unit at MedStar Harbor Hospital or the NIH/NIA/Biomedical Research Center at Johns Hopkins Bayview campus in Baltimore for study procedures.
* No knowledge of having had SARS-CoV-2, the virus that causes COVID-19.

EXCLUSION CRITERIA:

An individual who meets any of the following criteria will be excluded from participation in

this study:

* Unable to verify identification of volunteer by state issued ID card, driver s license, or military ID. Participants earning greater than $600.00/year are issued a 1099 form, therefore, positive identification is required.
* Unable to provide informed consent.
* Current use of steroids, immunosuppressive medications, radiation therapy, or chemotherapy medications.
* Pregnancy.

In addition, eligible participants may not be immediately able to participate in the study but might be eligible at a later date. These include:

* Symptoms of a viral infection on visit 1 (defer until resolved).
* Medication: Volunteers taking the following medications would be deferred for 2 weeks after course has been completed and volunteer is feeling well: Antibiotics, antifungals, antimalarials, antivirals.
* Temporary steroids (tapers): Deferred for 72 hours after symptoms are resolved and prescription is completed if taken orally, intravenously, or intramuscular. No deferral if taken intranasal, inhaled, or for joint injection.
* Infection or Fever: Deferred until 2 weeks after antibiotics are completed and /or volunteer is feeling well.
* We wish to only select healthy confirmed COVID-19 negative patients. Therefore, those who may have a household member (co-habitant) who is newly diagnosed with COVID-19 or who has symptoms will be deferred for 14 days.
* Treatment with another investigational drug or other intervention within 14 days of visit 1 per the discretion of the Principal Investigator.

Where this trial is running

Baltimore, Maryland and 1 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions COVID-19LongevityCellular ImmuneAntibodiesNatural History
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.