Phase 3 N=192 Randomized Quadruple-blind Prevention

Clinical Trial to Evaluate the Immunogenicity of an Adjuvanted Influenza Vaccine Among HCP

Influenza

Bottom Line

View on ClinicalTrials.gov: NCT06054269 ↗

Enrolled (actual)

192

Serious AEs

0.0%

Results posted

May 2025

Primary outcome: Primary: Hemagglutination Inhibition (HI) Geometric Mean Titers (GMT) Post-vaccination (Day 28) of Each Vaccine Reference Virus — 584.2; 342.8; 217.4; 169.0 antibody titer — p=0.004

Study Design & Population

Study type: Interventional
Phase: Phase 3
Interventions: FLUAD Quadrivalent (Biological); FluQuadri (Biological)
Age: Adult, Older Adult · 18+ yrs
Sex: All
Sponsor: Centers for Disease Control and Prevention
Primary completion: Jul 2023

Outcome Measures

Outcome	Result	p-value
PRIMARY Hemagglutination Inhibition (HI) Geometric Mean Titers (GMT) Post-vaccination (Day 28) of Each Vaccine Reference Virus	584.2; 342.8; 217.4; 169.0; 102.1; 107.8	0.004 sig
PRIMARY HI GMT Post-vaccination (6 Months) of Each Vaccine Reference Virus	177.4; 128.4; 94.1; 67.2; 34.5; 41.2	0.164
PRIMARY Seroconversion Rate (SCR) to Each Vaccine Reference Virus Post-vaccination	88.4; 62.1; 82.1; 62.1; 47.4; 52.6	<0.001 sig
PRIMARY SCR to Each Vaccine Reference Virus Post-vaccination	53.2; 41.7; 50.0; 39.6; 18.1; 28.1	0.112
PRIMARY Seroprotection Rate (SPR) to Each Vaccine Reference Virus Post-vaccination	98.9; 94.7; 95.8; 94.7; 81.1; 76.8	0.097
PRIMARY SPR to Each Vaccine Reference Virus Post-vaccination	93.6; 88.5; 90.4; 74.0; 55.3; 56.2	0.220

Summary

This randomized, double-blinded trial will assess humoral immune responses to adjuvanted, egg-based quadrivalent influenza vaccines compared to standard dose, egg-based quadrivalent influenza vaccines among healthcare personnel (HCP). The trial will be conducted at two sites in Lima, Peru during 2022 and 2023.

Eligibility Criteria

Inclusion Criteria

≥18 years old;
Have participated in the healthcare personnel cohort study at Hospital Nacional Cayetano Heredia or Hospital Nacional Arzobispo Loayza during 2016-2021;
Work at the facility full-time (≥30 hours per week);
Have routine, direct, hands-on or face-to-face contact with patients (≤1 meter) as part of a typical work shift, including, but not limited to, physicians, nurses, respiratory therapists, physical therapists, unit clerks, radiograph technicians, medical assistants, and transporters;
Work at the facility for ≥1 year prior to enrollment and planning to continue working at the facility for one year after enrollment;
Willing to receive influenza vaccination (adjuvanted or standard dose);
Women of childbearing age must complete the following criteria to be eligible:
Have a negative urine pregnancy test performed by the study staff ≤24 hours preceding receipt of the vaccine;
Be willing to use a reliable form of contraception approved by the Investigator for ≤2 months after receiving the vaccine. If they are not currently using an approved contraceptive, study staff will provide access to contraceptives;
Must not be breastfeeding.

Exclusion Criteria

Have received a vaccine against influenza during the 2022 influenza season (season of clinical trial);
Have a severe, life-threatening allergy to influenza vaccines, eggs, or influenza vaccine components;
Have a history of Guillain-Barre Syndrome or other autoimmune diseases;
Received blood or blood products within 3 months of enrollment;
Be pregnant, confirmed by rapid pregnancy test.

View full record on ClinicalTrials.gov →

Data sourced from ClinicalTrials.gov (NCT06054269). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.