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NCT Number: NCT03734237

A Pragmatic Assessment of Influenza Vaccine Effectiveness in the DoD

A total of 18,000 eligible subjects (or 6,000 subject distributed evenly between the 3 study arms) will be enrolled. Eligible subjects will be randomized in 1:1:1 (cell-culture-based vaccine, the recombinant vaccine, or the egg-based vaccine) over four influenza seasons (2018-2019, 2019-2020, 2020-2021, and 2021-2022).

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This study is active but is not currently recruiting participants.

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Key information

Conditions

Influenza Infections Influenza Vaccines Influenza, Human Influenza-like Illness Orthomyxoviridae Infections RNA Virus Infections Respiratory Tract Diseases Respiratory Tract Infections Virus Diseases

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 4

Primary location

Naval Medical Center San Diego, San Diego, California, United States

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About this study

This four-year, pragmatic, prospective study will compare the effectiveness of licensed egg-based inactivated influenza vaccines to the effectiveness of two other types of licensed vaccines, the cell-culture based inactivated influenza vaccine and the recombinant influenza vaccine, in the prevention of laboratory-confirmed influenza infection in active duty members, military retirees, and other DoD beneficiaries. Military treatment facilities (MTFs) in the United States will participate in this protocol. Enrollment will be restricted to adults (≥18 years and older) who are preparing to receive seasonal influenza vaccination at participating DoD sites. Subjects will be randomized to receive one of the three licensed influenza vaccines types for evaluation of effectiveness. There is no exclusion for pregnancy, as none of these licensed products are contraindicated in pregnant women.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Eligible for care in Department of Defense medical facilities (Defense Enrollment Eligibility Reporting System eligible)
  • ≥18 years of age.
  • At a participating Military Treatment Facility site for the purpose of receiving a seasonal (2018-2019, 2019-2020,2020-2021, 2021-2022) influenza vaccination.
  • Able to speak English and able to provide informed consent
  • Able to receive and respond to texts and/or emails, or a military recruit

Exclusion criteria

  • Adults intending to receive or who have received the current seasons FluMist Vaccine (LAIV)
  • Adults who have already received a flu vaccine within the current season
  • Individual who cannot receive a flu vaccine or standard dosing due to another medical condition
  • Allergic to gentamicin, polymyxin and/or neomycin
  • Individuals who fail to meet the inclusion criteria

Treatment and study plan

Egg based influenza vaccines

Biological

Participants will be randomly allocated to one of three vaccine types in accordance with standard clinical practices for those in the US military. All vaccines are FDA licensed for use in the United States.

Recombinant influenza vaccines

Biological

Participants will be randomly allocated to one of three vaccine types in accordance with standard clinical practices for those in the US military. All vaccines are FDA licensed for use in the United States.

Cell-culture based influenza vaccines

Biological

Participants will be randomly allocated to one of three vaccine types in accordance with standard clinical practices for those in the US military. All vaccines are FDA licensed for use in the United States.

Primary outcomes

  1. Number of Participants With Laboratory Confirmed Influenza

    Time frame: Onset > 13 days after vaccination up to 1 year

    Laboratory-confirmed influenza as ascertained by a sensitive and specific assay.

Secondary outcomes

  1. Hemagglutination Inhibition (HI) Titer Responses to Influenza Vaccine Strains.

    Time frame: Baseline to 21-35 days post vaccine

    Strain-specific seroconversion rate determined by reference hemagglutination inhibition assay.

  2. Pseudovirion Neutralization (PVN) Responses to Influenza Vaccine.

    Time frame: Baseline to 21-35 days post vaccine

    Neutralizing antibody responses (4-fold rise) to HA-psuedoviruses corresponding to vaccine-matched viruses, recently circulating influenza virus, and emerging influenza strain.

  3. Anti-Neuraminidase (Anti-NA) Titer Responses to Influenza Vaccine.

    Time frame: Baseline to 21-35 days post vaccine

    Anti-Neuraminidase (Anti-NA) titer responses determined by enzyme linked immuno-assay.

  4. Number of Participants With Influenza-Like Illness

    Time frame: Onset > 13 days after vaccination up to 1 year

    Rate of protocol defined influenza-like illness ascertained by participant response to active surveillance.

Other outcomes

  1. Number of Participants With SARS-CoV-2 and Influenza Co-Infection

    Time frame: Onset > 13 days after influenza vaccination up until one year

    Laboratory-confirmed SARS CoV2, and SARS CoV2 plus influenza co-infection, as ascertained by nasal swab PCR.

  2. Symptom Severity of SARS CoV2

    Time frame: onset >13 days after Influenza vaccination up to 1 year

    Symptom severity scores were reported by participants using FLU-PRO Plus (Influenza Patient Reported Outcomes), a standardized instrument developed to measure the intensity and frequency of viral respiratory tract symptoms. FluPRO Plus symptom scores range from 0 ("not at all") to 4 ("very much"), with higher scores indicating greater severity.

Sponsors and collaborators

Lead sponsor

Henry M. Jackson Foundation for the Advancement of Military Medicine

Other

Collaborators

  • Defense Health Agency
  • Food and Drug Administration (FDA)
  • National Institute of Allergy and Infectious Diseases (NIAID)
  • Naval Health Research Center
  • US Department of Defense Armed Forces Health Surveillance Center
  • Uniformed Services University of the Health Sciences
  • United States Air Force School of Aerospace Medicine

Registry information

Acronym: PAIVED

Important dates

Study start
2018
Primary completion
2022
Study completion
2026
First posted
Nov 7, 2018
Registry last updated
Apr 2, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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