Clinical trialNCT04025580CompletedPhase 2Interventional

Systems Analyses of the Immune Response to the Seasonal Influenza Vaccine

SponsorNational Institute of Allergy and Infectious Diseases (NIAID)Enrollment98Healthy Volunteer

View the registry record on ClinicalTrials.gov

Summary

The lay summary the sponsor registered on ClinicalTrials.gov.

Background: Vaccines help prevent disease by causing the body to have an immune response. Many parts of this response happen in the blood. This response happens over days and weeks after getting the vaccine. Researchers want to how the blood changes over time in response to vaccines. They want to find out why vaccines work better for some people than for others. This could help make more effective vaccines. Objective: To learn about how the body responds to vaccines. Eligibility: Healthy people ages 18 and older Design: Participants will be screened with a medical history, physical exam, and blood and urine tests. Participants will have 9 visits over 6 months. All visits will include blood tests and a physical exam. Participants will have the first visit 1 week before they get the vaccine. Participants will get the flu vaccine at the second visit. The vaccine will be injected into the muscle of the upper arm with a needle. They will be watched for side effects for 15 minutes. Participants will have the next 2 visits exactly 1 day and 1 week after they get the vaccine. They will have the other 5 visits about 14, 28, 70, and 100 days after they get the vaccine. Participants will take email questionnaires about whether they had any side effects. Participants may have optional extra study visits. These will be no more than once a month for up to 1 year after they get the vaccine. Optionally, they can also repeat the study each year through the 2023 - 2024 flu season

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Investigators

The overall officials registered on this study. Names that resolve to a FindMyKOL profile link to it; the rest are shown as registered.

Rachel D Sparks, M.D.
National Institute of Allergy and Infectious Diseases (NIAID)
Principal Investigator
clinicaltrials.gov ↗

A profile link is shown only when the registered name resolves to a person record with a confident, namesake-checked match; ambiguous names stay unlinked.

Sites

1 registered facility, with the per-site recruitment status where the registry publishes one. ClinicalTrials.gov does not publish per-site enrollment counts.

United States

National Institutes of Health Clinical Center
Bethesda, Maryland, United States

Site investigator names are published by ClinicalTrials.gov only while a study recruits, so completed studies list sites without them.

Drugs studied

The drug and biological interventions registered on this study, normalized to their RxNorm ingredient where possible.

Flucelvax →FluvirinFluzone High Dose →

Linked drugs open the directory filtered to KOLs working with them.clinicaltrials.gov ↗

Registration & key dates

Registry attributes as recorded on the ClinicalTrials.gov study record.

Start: 2 Oct 2019
Primary completion: 31 Jan 2023
Completion: 31 Jan 2023
Last update posted: 2 Jan 2024
Registered enrollment: 98
Registry id: NCT04025580

clinicaltrials.gov ↗

Source: ClinicalTrials.gov, via the CTTI AACT database, data as of 4 Nov 2026. Registry facts are shown as registered by the study sponsor; FindMyKOL does not interpret them.