Recombinant Influenza Vaccine Versus Standard Egg-Based Inactivated Influenza Vaccine in Adults 18-64 Years

NCT05514002 | Completed Phase 4 Results FDA Drug

• 1 other identifier: 0900f3eb81f9905e
• Study Type: interventional
• Target: 3,988
• Locations: 1 country
• Sites: 4

Brief Summary

This randomized, active comparator trial will compare the clinical efficacy of recombinant influenza vaccine (RIV) to standard-dose egg-based inactivated influenza vaccine (SD IIV) among adults aged 18-64 years. The primary study hypothesis is that the clinical efficacy of RIV is superior to that of SD IIV to prevent and attenuate influenza-like illness (ILI)-associated influenza virus infection. Relative efficacy will be assessed by comparing rates of ILI-associated reverse transcription polymerase chain reaction (RT-PCR)-confirmed influenza virus infection and measures of infection and illness attenuation among participants who receive RIV versus SD IIV. A secondary hypothesis is that humoral and cell-mediated immune responses to RIV are superior to responses to SD IIV. Relative immunogenicity will be assessed by comparing markers of humoral and cell-mediated immune responses post-vaccination among a subset of participants who receive RIV versus SD IIV.

Conditions

Influenza, Human

Outcome Measures

Primary Outcomes (1)

• RT-PCR-Confirmed Influenza Infection

  Number of participants with RT-PCR-confirmed influenza infection during the influenza circulation period. Relative vaccine effectiveness (rVE) was calculated as (1 - hazard ratio comparing RIV vs SD-IIV) × 100%.

  From ≥14 days after vaccination through end of surveillance (up to 16 weeks)

Secondary Outcomes (1)

• Time to Return to Usual Health Following Influenza Illness

  Up to 14 days after onset of influenza illness

Study Arms (2)

Recombinant Influenza Vaccine (RIV)

ACTIVE COMPARATOR

recombinant vaccine Flublok® Quadrivalent

Biological: Flublok Quadrivalent

Standard-Dose Inactivate Influenza Vaccine (SD IIV)

ACTIVE COMPARATOR

egg-based vaccines Fluzone® Quadrivalent or Fluarix® Quadrivalent at approximately 28 days after receipt of the 2018-19 and 2019-20 vaccines

Biological: Fluzone Quadrivalent

Interventions

Flublok Quadrivalent BIOLOGICAL

Intramuscular

Recombinant Influenza Vaccine (RIV)

Fluzone Quadrivalent BIOLOGICAL

Intramuscular

Standard-Dose Inactivate Influenza Vaccine (SD IIV)

Eligibility Criteria

• Age: 18 Years - 64 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Aged 18-64 years
• Comfortable reading and responding to text messages or emails sent in either English, Spanish, or Chinese
• Currently enrolled as a student in a college or graduate degree program AND attending in-person classes with other students.
• OR Currently employed as a frontline worker defined as an occupation that cannot be done from home or alone AND have direct face-to-face contact, defined as being within 6 feet, or about two arms' lengths, with co-workers, patients or the public as part of full-time (at least 20 hours per week) job responsibilities.
• Have daily access to the internet and a mobile phone that can send and receive text messages.
• Plan to continue to live/work in the study area through May 2023 (if trial season 1) or May 2024 (if trial season 2). For students in college or graduate degree programs, this is defined as living/working in the area excluding brief absences during school vacation periods.

You may not qualify if:

• Lives with another person who is already enrolled in this study as reported by the subject.
• Previous hypersensitivity reaction to the study vaccines as reported by the subject.
• Has already received current year influenza vaccine on our after July 1, 2022 as reported by the subject.

Sponsors & Collaborators

• Westat: collaborator
• University of Arizona: collaborator
• Florida A&M University: collaborator
• Baylor College of Medicine: collaborator
• University of Utah: collaborator
• Centers for Disease Control and Prevention: lead

Study Sites (4)

University of Arizona

Tucson, Arizona, 85724, United States

Location

Florida A&M University

Tallahassee, Florida, 32307, United States

Location

Baylor College of Medicine

Houston, Texas, 77030, United States

Location

University of Utah

Salt Lake City, Utah, 84119, United States

Location

Related Publications (1)

• Grant L, Whitaker JA, Yoon SK, Lutrick K, Bhargava S, Brown CP, Zaragoza E, Fink RV, Meece J, Wielgosz K, El Sahly H, Hegmann KT, Lowe AA, Southworth A, Tatum T, Ball SW, Levine MZ, Thiese MS, Battan-Wraith S, Barnes J, Phillips AL, Fry AM, Dawood FS; Randomized Assessment of Influenza Vaccine Efficacy Network (RAIVEN). Relative Effectiveness and Immunogenicity of Quadrivalent Recombinant Influenza Vaccine Versus Egg-Based Inactivated Influenza Vaccine Among Adults Aged 18-64 Years: Results and Experience From a Randomized, Double-Blind Trial. Open Forum Infect Dis. 2024 Sep 26;11(10):ofae559. doi: 10.1093/ofid/ofae559. eCollection 2024 Oct.

  PMID: 39416990 DERIVED

MeSH Terms

Conditions

Influenza, Human

Condition Hierarchy (Ancestors)

Respiratory Tract Infections; Infections; Orthomyxoviridae Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases

Limitations and Caveats

Enrollment was lower than planned because the study ended after a single influenza season due to funding constraints, resulting in approximately 25% of the target sample size and limited statistical power to detect differences in relative vaccine effectiveness. The study was conducted during a single influenza season, which may limit generalizability to other seasons.

Results Point of Contact

• Title: Fatimah S. Dawood, MD
• Organization: Centers for Disease Control and Prevention

fdawood@cdc.gov

404.639.0431

Study Officials

• Fatimah S Dawood, MD

  Centers for Disease Control and Prevention

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: FED
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal investigator

Study Record Dates

• First Submitted: August 8, 2022
• First Posted: August 24, 2022
• Study Start: September 13, 2022
• Primary Completion: December 31, 2023
• Study Completion: December 31, 2023
• Last Updated: July 30, 2026
• Results First Posted: July 30, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL
• Time Frame: Upon the completion of all study deliverables and dissemination of analyses to meet the protocol objectives.

Locations

US (4)