Study on a High-Dose Quadrivalent Influenza Vaccine Compared With Standard-Dose Quadrivalent Influenza Vaccine in Children 6 Months Through 35 Months of Age

NCT ID: NCT04544267

Last Updated: 2025-12-24

Study Results

Results available

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Basic Information

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Recruitment Status

TERMINATED

Clinical Phase

PHASE3

Total Enrollment

100 participants

Study Classification

INTERVENTIONAL

Study Start Date

2020-09-15

Study Completion Date

2021-06-02

Brief Summary

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The primary objective of the study was to compare the clinical efficacy of high-dose quadrivalent influenza vaccine (QIV-HD) to standard-dose quadrivalent influenza vaccine (QIV-SD) in participants 6 months through 35 months of age for the prevention of laboratory-confirmed influenza illness caused by any influenza A or B type.

The secondary objectives of the study were:

* To compare QIV-HD to QIV-SD:
* in participants 6 months through 35 months of age for the prevention of laboratory-confirmed influenza illness caused by any influenza A or B type using a more stringent threshold
* in participants 6 months through 35 months of age for the prevention of laboratory-confirmed protocol-defined influenza-like illness caused by viral strains similar to those contained in the vaccine.
* in participants 6 months through 23 months of age for the prevention of laboratory-confirmed influenza illness caused by any influenza A or B types.
* To compare hemagglutination inhibition (HAI) immune response of QIV-HD to QIV-SD in participants 6 months through 35 months of age
* To describe the HAI, seroneutralization (SN), and anti-neuraminidase (NA) immune response
* To describe the immune response to revaccination in Season 3 (Northern Hemisphere)
* To describe the safety profile of each vaccine

Detailed Description

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The study was planned to start in the second half of 2020 with the Sentinel Safety Cohort. Following the Sentinel Safety Cohort, the main efficacy cohort was to be conducted during the 2021-2022 Northern Hemisphere influenza season (Season 1), the 2021-2022 Southern Hemisphere influenza season (Season 2), and the 2021-2022-2023 Northern Hemisphere influenza season (Season 3).

Participants received either 1 or 2 doses of the study vaccine depending on whether they were previously influenza vaccinated or previously influenza unvaccinated, respectively.

Study duration per participant was approximately 6 to 7 months.

Conditions

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Influenza

Study Design

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Allocation Method

RANDOMIZED

Intervention Model

PARALLEL

A sentinel safety cohort was selected for collection safety events where QIV-HD was administered open-label in 100 participants. These subjects did not provide blood samples and were not followed for influenza-like illness (ILI) surveillance.

A re-vaccination cohort was composed of a subset of approximately 120 participants from Season 1 (2021-2022 Northern Hemisphere) were re-enrolled and re-randomized in Season 3. The re-vaccination cohort was included, re-randomized to receive either QIV-HD or QIV-SD, provided blood samples in Season 1 and Season 3, and were not followed for ILI surveillance during their participation in Season 3.
Primary Study Purpose

PREVENTION

Blinding Strategy

QUADRUPLE

Participants Caregivers Investigators Outcome Assessors
A total of 100 participants were in an uncontrolled, open-label sentinel cohort, while all other participants were in an randomized, modified double-blind design. The following measures ensured the integrity of the blinded data for the participants in the randomized, modified double-blind cohort:

* The unblinded qualified study staff member, independent of the safety evaluation and other study evaluations, administered the vaccine
* The Investigators (or delegates) in charge of safety assessment, the study staff who collect the safety data, and the laboratory personnel who analyze the blood samples did not know which product was administered
* The participant / parent / guardian did not know which product was administered. To maintain the blinding of the participant / parent / guardian, the vaccine syringe label was covered with appropriate materials prior to administration.

Study Groups

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QIV-HD

One injection of QIV-HD on Day 0. For participants for whom 2 doses of influenza vaccine were recommended, a second dose was administered on Day 28.

Group Type EXPERIMENTAL

Quadrivalent influenza vaccine, high-dose

Intervention Type BIOLOGICAL

Pharmaceutical form: suspension for injection in a pre-filled syringe; route of administration: intramuscular

QIV-SD

One injection of QIV-SD on Day 0. For participants for whom 2 doses of influenza vaccine were recommended, a second dose was administered on Day 28.

Group Type ACTIVE_COMPARATOR

Quadrivalent influenza vaccine, standard dose

Intervention Type BIOLOGICAL

Pharmaceutical form: suspension for injection in a pre-filled syringe; route of administration: intramuscular

Interventions

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Quadrivalent influenza vaccine, high-dose

Pharmaceutical form: suspension for injection in a pre-filled syringe; route of administration: intramuscular

Intervention Type BIOLOGICAL

Quadrivalent influenza vaccine, standard dose

Pharmaceutical form: suspension for injection in a pre-filled syringe; route of administration: intramuscular

Intervention Type BIOLOGICAL

Eligibility Criteria

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Inclusion Criteria

* Aged 6 to 35 months on the day of the first study visit
* Informed consent form was signed and dated by the parent(s) or guardian(s) and by an independent witness, if required by local regulations.
* Participant and parent / guardian who were able to attend all scheduled visits and to comply with all study procedures.
* Covered by health insurance if required by local regulations
* For Season 3 Re-vaccination Cohort: eligible participants must have been enrolled in the Season 1 (2021-2022 Northern Hemisphere season) immunogenicity subset and must have completed all study procedures (ie, blood draws and vaccinations) in Season 1.

Exclusion Criteria

* Participation at the time of study enrollment (or in the 4 weeks preceding the first study vaccination) or planned participation during the present study period in another clinical study investigating a vaccine, drug, medical device, or medical procedure.
* For all participants: Receipt of any vaccine in the 30 days preceding the first study vaccination. For participants in immunogenicity subset: Planned receipt of any vaccine before Visit 2 for participants receiving 1 dose of influenza vaccine or Visit 3 for participants receiving 2 doses of influenza vaccine.
* Previous vaccination against influenza in the preceding 6 months with either the study vaccine or another influenza vaccine
* Receipt of immune globulins, blood or blood-derived products in the past 3 months.
* Known or suspected congenital or acquired immunodeficiency (eg, HIV); or receipt of immunosuppressive therapy, such as anti-cancer 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).
* 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. Exception: participants with an egg allergy are allowed to enroll in the study.
* Thrombocytopenia, bleeding disorder, or receipt of anticoagulants that based on Investigator's judgment contraindicate intramuscular vaccination
* Chronic illness that, in the opinion of the investigator, was at a stage where it might interfere with study conduct or completion.
* Moderate or severe acute illness/infection (according to investigator judgment) on the day of vaccination or febrile illness (temperature ≥ 38.0 C \[≥ 100.4 F\]). A prospective participant would not be included in the study until the condition was resolved or the febrile event was subsided.
* Identified as natural or adopted child of the Investigator or employee with direct involvement in the proposed study.
* Personal or family history of Guillain-Barre Syndrome.
* Any condition that in the opinion of the Investigator would pose a health risk to the participant if enrolled or could interfere with the evaluation of the vaccine.
* Personal history of clinically significant development delay (at the discretion of the Investigator), neurologic disorder, or seizure disorder.
* For Season 3 (2022-2023 Northern Hemisphere) main cohort: participants who were enrolled in a previous study season are excluded from Season 3, with the exception of the Re-vaccination Cohort.

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

6 Months

Maximum Eligible Age

35 Months

Eligible Sex

ALL

Accepts Healthy Volunteers

Yes

Sponsors

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Sanofi Pasteur, a Sanofi Company

INDUSTRY

Sponsor Role lead

Responsible Party

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Responsibility Role SPONSOR

Principal Investigators

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Clinical Sciences & Operations

Role: STUDY_DIRECTOR

Sanofi Pasteur, a Sanofi Company

Locations

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California Research Foundation Site Number : 8400008

San Diego, California, United States

Site Status

Acevedo Clinical Research Associates Site Number : 8400007

Miami, Florida, United States

Site Status

Emory Childrens Center- Site Number : 8400001

Atlanta, Georgia, United States

Site Status

Heartland El Dorado- Site Number : 8400032

El Dorado, Kansas, United States

Site Status

Kentucky Pediatrics / Adult Research- Site Number : 8400005

Bardstown, Kentucky, United States

Site Status

Velocity Clinical Research- New Orleans Site Number : 8400009

New Orleans, Louisiana, United States

Site Status

Ohio Pediatric Research- Site Number : 8400027

Dayton, Ohio, United States

Site Status

Rainbow Pediatrics- Site Number : 8400033

Barnwell, South Carolina, United States

Site Status

Cenexel JBR- Site Number : 8400006

Salt Lake City, Utah, United States

Site Status

Foothill Family Clinic South- Site Number : 8400045

Salt Lake City, Utah, United States

Site Status

Countries

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United States

Provided Documents

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Document Type: Study Protocol

View Document

Document Type: Statistical Analysis Plan

View Document

Related Links

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Other Identifiers

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U1111-1243-5993

Identifier Type: REGISTRY

Identifier Source: secondary_id

QHD00014

Identifier Type: OTHER

Identifier Source: secondary_id

2019-004721-24

Identifier Type: EUDRACT_NUMBER

Identifier Source: secondary_id

QHD00014

Identifier Type: -

Identifier Source: org_study_id