CompletedNCT04451954FBP00004Updated Sep 17, 2025

Study of Recombinant Influenza Vaccine Containing Different H3 Antigens Without or With Adjuvant in Healthy Adult Subjects

A Phase 1 interventional study of Quadrivalent RIV with H3 strain 1 and Quadrivalent RIV with H3 strain 1 and adjuvant in Influenza Immunisation and Healthy Volunteers, sponsored by Sanofi Pasteur, a Sanofi Company. Completed at 5 sites in United States. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-09-17.

Sponsored by Sanofi Pasteur, a Sanofi Company · Phase 1, Interventional, and Prevention

From the registry’s dates

Primary completion was Sep 2021, 5 years ago, and no results have been posted to the registry.

Phase: Phase 1
Study type: Interventional
Enrollment: 210
Allocation: Randomized
Ages: 18 Years and older
Sex: All

Study summary

The primary objectives of the study are:

To describe the safety profile of the different formulations in all participants
To describe the hemagglutinin inhibition (HAI) and seroneutralization (SN) antibody responses against hemagglutinin (H1, H3, B/Victoria, and B/Yamagata) antigens present in the control vaccine in all groups at all timepoints.

The secondary objectives are:

To describe antigenic coverage in each group by assessing the HAI and SN antibody responses against a panel of H3 antigens (not present in any of the vaccine formulations).
To describe SN antibody responses in each group against each of the H3 antigens.
To compare H3 HAI and SN antibody responses for the groups with quadrivalent recombinant influenza vaccine (RIV) formulations with H3 antigens to those of the quadrivalent RIV control group.
To compare the HAI and SN antibody responses for the groups with quadrivalent RIV formulation with adjuvant to the group without adjuvant.

Read the detailed description

Study duration per participant is approximately 1 year

Conditions studied

Influenza Immunisation
Healthy Volunteers

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Influenza, Human 2,214

In context

Influenza, Human

2,214 studies on the registry are indexed under Influenza, Human; 163 are open to participants now.

This study's enrollment of 210 is below the median of 238 across 1,853 interventional studies indexed under Influenza, Human.

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Lead sponsor

Sanofi Pasteur, a Sanofi Company is the lead sponsor of 366 studies on the registry; 4 are open to participants now.

Of its 94 completed or terminated interventional studies of FDA-regulated products, 73 (78%) have results posted.

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 18 Years and older
Sexes eligible: All
Accepts healthy volunteers: Yes

Inclusion criteria

Older adults: Aged 50 years and older on the day of inclusion Young adults: Aged 18 to 30 years on the day of inclusion
Informed consent form has been signed and dated
Able to attend all scheduled visits and to comply with all trial procedures

Exclusion criteria

Exclusion criteria:

Participant is pregnant, or lactating, or of childbearing potential and not using an effective method of contraception or abstinence from at least 4 weeks prior to vaccination until at least 12 weeks postvaccination. To be considered of non-childbearing potential, a female must be premenarche, or postmenopausal for at least 1 year, or surgically sterile
Participation at the time of study enrollment (or in the 4 weeks preceding the study vaccination) or planned participation during the present study period in another clinical study investigating a vaccine, drug, medical device, or medical procedure
Receipt of any vaccine in the 4 weeks preceding the study vaccination or planned receipt of any vaccine in the 4 weeks following study vaccination
Previous vaccination against influenza during either of the previous 2 influenza seasons (2018-2019 and 2019-2020) with any licensed or investigational influenza vaccine
Receipt of immune globulins, blood, or blood-derived products in the past 3 months
Known or suspected congenital or acquired immunodeficiency; immunosuppressive therapy (such as anticancer chemotherapy or radiation therapy, within the preceding 6 months); or long-term systemic corticosteroid therapy (prednisone or equivalent for more than 2 consecutive weeks within the past 3 months) or receipt of hydroxychloroquine within the preceding 4 weeks
Dementia or any other cognitive condition at a stage that could interfere with following the trial procedures
Have known active or recently active (12 months) neoplastic disease or a history of any hematologic malignancy
History of influenza infection during either of the previous 2 influenza seasons (2018- 2019 or 2019-2020), confirmed by laboratory tests (including rapid tests) at that time
History of laboratory confirmed coronavirus disease 2019 (COVID-19), confirmed with a nucleic acid amplification test on a respiratory specimen, or known exposure to severe acute respiratory syndrome coronavirus (SARS-CoV-2) positive confirmed close contact (eg, family member, housemate, daycare provider, aged parent requiring care), in the 30 days preceding vaccination, at the discretion of the investigator
Self-reported or documented seropositivity for human immunodeficiency virus, hepatitis B, or hepatitis C
Known systemic hypersensitivity to any of the vaccine components, or history of a life-threatening reaction to the vaccines used in the study or to a vaccine containing any of the same substances
Have any diagnosis, current or past, of an autoimmune disease
Thrombocytopenia or bleeding disorder, contraindicating intramuscular vaccination based on investigator's judgment
Deprived of freedom by an administrative or court order, or in an emergency setting, or hospitalized involuntarily
Any change in chronic prescription medication or change in medication dose or dosage in the 60 days prior to enrollment
Alcohol abuse or substance abuse that, in the opinion of the investigator, might interfere with the study conduct or completion
Chronic illness that, in the opinion of the investigator, is at a stage where it might interfere with study conduct or completion
Any current or past diagnosis of chronic pulmonary disease including asthma (history of childhood asthma is allowed), cystic fibrosis and chronic pulmonary obstructive disease
Have taken a high-dose inhaled corticosteroid within 6 months prior to study vaccination
Body mass index of 40 or higher
Any current or past diagnosis of cardiac disease (eg, coronary artery disease, heart failure, or valvular heart disease [mild mitral valve prolapse allowed]). Participants with isolated primary (essential) hypertension are allowed
Moderate or severe acute illness/infection (according to investigator judgment) on the day of vaccination or febrile illness (oral temperature ≥100.4 F [≥38.0 C]). A prospective participant should not be included in the study until the condition has resolved or the febrile event has subsided
Identified as an investigator or employee of the investigator or study center with direct involvement in the proposed study, or identified as an immediate family member (ie, parent, spouse, natural or adopted child) of the investigator or employee with direct involvement in the proposed study
Personal or family history of Guillain-Barré syndrome
History of chronic kidney disease
Current or past diagnosis of thyroid disease (eg, thyroiditis [including Hashimoto's thyroiditis], hyperthyroidism, and hypothyroidism)

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.

Study design

Phase: Phase 1
Primary purpose: Prevention
Allocation: Randomized
Intervention model: Parallel assignment
Masking: Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment: 210 participants (actual)

Study arms

Experimental
Group 1: Quadrivalent RIV with H3 strain 1, without adjuvant
1 injection of quadrivalent RIV containing H3 strain 1, without adjuvant, in participants ≥ 50 years old
Biological: Quadrivalent RIV with H3 strain 1
Experimental
Group 2: Quadrivalent RIV with H3 strain 1, with adjuvant
1 injection of quadrivalent RIV containing H3 strain 1, with adjuvant, in participants ≥ 50 years old
Biological: Quadrivalent RIV with H3 strain 1 and adjuvant
Experimental
Group 3: Quadrivalent RIV with H3 strain 2, without adjuvant
1 injection of quadrivalent RIV containing H3 strain 2, without adjuvant, in participants ≥ 50 years old
Biological: Quadrivalent RIV with H3 strain 2
Experimental
Group 4: Quadrivalent RIV with H3 strain 2, with adjuvant
1 injection of quadrivalent RIV containing H3 strain 2, with adjuvant, in participants ≥ 50 years old
Biological: Quadrivalent RIV with H3 strain 2 and adjuvant
Active comparator
Group 5: Quadrivalent RIV Control, without adjuvant
1 injection of quadrivalent RIV containing 2018-19 Northern Hemisphere (NH) recommended H3 strain, without adjuvant, in participants ≥ 50 years old
Biological: Quadrivalent RIV with 2018-2019 NH H3 strain
Active comparator
Group 6: Quadrivalent RIV Control, with adjuvant
1 injection of quadrivalent RIV containing 2018-19 NH recommended H3 strain, with adjuvant, in participants ≥ 50 years old
Biological: Quadrivalent RIV with 2018-2019 NH H3 strain and adjuvant
Active comparator
Group 7: Quadrivalent RIV Control, without adjuvant
1 injection of quadrivalent RIV containing 2018-19 NH recommended H3 strain, without adjuvant, in participants 18-30 years old
Biological: Quadrivalent RIV with 2018-2019 NH H3 strain

Interventions

BiologicalQuadrivalent RIV with H3 strain 1
Pharmaceutical form: Suspension for injection Route of administration: Intramuscular
BiologicalQuadrivalent RIV with H3 strain 1 and adjuvant
Pharmaceutical form: Suspension for injection Route of administration: Intramuscular
BiologicalQuadrivalent RIV with H3 strain 2
Pharmaceutical form: Suspension for injection Route of administration: Intramuscular
BiologicalQuadrivalent RIV with H3 strain 2 and adjuvant
Pharmaceutical form: Suspension for injection Route of administration: Intramuscular
BiologicalQuadrivalent RIV with 2018-2019 NH H3 strain
Pharmaceutical form: Suspension for injection Route of administration: Intramuscular
BiologicalQuadrivalent RIV with 2018-2019 NH H3 strain and adjuvant
Pharmaceutical form: Suspension for injection Route of administration: Intramuscular

What researchers measure

Primary outcomes

Number of participants with immediate adverse events
Immediate adverse events are unsolicited systemic adverse events reported in the 30 minutes after vaccination
Time frame: Within 30 minutes after vaccination
Number of participants with solicited injection site or systemic reactions
Solicited injection site reactions: injection site pain, erythema, swelling, induration and bruising; solicited systemic reactions: fever, headache, malaise, and myalgia
Time frame: From Day 0 to Day 7
Number of participants with unsolicited adverse events
Unsolicited (spontaneously reported) adverse events not not fulfilling criteria for solicited reactions
Time frame: From Day 0 to Day 28
Number of participants with serious adverse events
Serious adverse events are collected throughout the study
Time frame: From Day 0 to Day 365
Number of participants with adverse events of special interest
Adverse events of special interest are collected throughout the study
Time frame: From Day 0 to Day 365
Clinical safety laboratory test results
Laboratory tests include complete blood count (CBC), platelet count, alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin, serum creatinine, serum lipase, and serum amylase)
Time frame: From Day 0 to Day 7
HAI and SN antibody titers against influenza antigens in the quadrivalent RIV control vaccine
Influenza antibody titers are measured by HAI and SN assays
Time frame: From Day 0 to Day 365
Individual HAI and SN titers ratio against influenza antigens in the quadrivalent RIV control vaccine
Titers ratio is calculated for the following time points: Day 7/Day 0, Day 28/Day 0, and Day 90/Day 0
Time frame: From Day 0 to Day 90
Number of participants with seroconversion to influenza antigens in the quadrivalent RIV control vaccine
Seroconversion is defined as HAI antibody titer \< 10 \[1/dil\] at Day 0 and post-injection titer ≥ 40 \[1/dil\] at Day 28, or titer ≥ 10 \[1/dil\] at Day 0 and a ≥ 4-fold increase in titer \[1/dil\] at Day 28)
Time frame: From Day 0 to Day 28
HAI Ab titer ≥ 40 [1/dil]
Influenza vaccine antibody titers are measured by HAI assay
Time frame: From Day 0 to Day 365
2-fold and 4-fold increase in SN titers
Influenza vaccine antibody titers are measured by SN assay
Time frame: From Day 0 to Day 28

Secondary outcomes

HAI antibody titers against influenza H3 antigens not present in the vaccine formulations and the SN antibody titers against each of the H3 antigens
Influenza vaccine antibody titers are measured by HAI and SN assays
Time frame: Day 0, Day 7, Day 28, Day 90, Day 180, and Day 365
Individual HAI titer ratios against influenza H3 antigens not present in the vaccine formulations and individual SN titer ratio against each of the H3 antigens
Titer ratio is calculated for the following time points: Day 7/Day 0, Day 28/Day 0, Day 90/Day 0
Time frame: From Day 0 to Day 90
Number of participants with seroconversion to influenza H3 antigens not present in the vaccine formulations
Seroconversion is defined as HAI antibody titer \< 10 \[1/dil\] at Day 0 and post-injection titer ≥ 40 \[1/dil\] at Day 28, or titer ≥ 10 \[1/dil\] at Day 0 and a ≥ 4-fold increase in titer \[1/dil\] at Day 28)
Time frame: Day 0 and Day 28
2-fold and 4-fold rise in SN antibody titers against each of the H3 antigens
Influenza vaccine antibody titers a are measured by SN assay
Time frame: Day 0, Day 7, Day 28, Day 90, Day 180, and Day 365

Study locations

5 sites

Investigational Site Number 8400003
San Diego, California 92108, United States
Investigational Site Number 8400002
Melbourne, Florida 32934, United States
Investigational Site Number 8400004
Orlando, Florida 32806, United States
Investigational Site Number 8400001
Peoria, Illinois 61614, United States
Investigational Site Number 8400005
Rockville, Maryland 20850, United States

References and documents

Individual participant data

Plan to share: Yes — Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org

Updates

Tracking since Sep 25, 2026

No changes since tracking began. The registry record was last updated on Sep 17, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT04451954
Lead sponsor: Sanofi Pasteur, a Sanofi Company
Responsible party: Sponsor
First posted: Jun 30, 2020
Start date: Jul 2, 2020
Primary completion: Sep 20, 2021
Completion: Sep 20, 2021
Last update: Sep 17, 2025

Study contacts

Clinical Sciences & Operations

study director · Sanofi Pasteur, a Sanofi Company

Oversight

Data monitoring committee: No
FDA-regulated drug: Yes
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Sep 2025. You cannot join it, but the record below documents what was studied.

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