Study on a High-Dose Quadrivalent Influenza Vaccine Compared With Standard-Dose Quadrivalent Influenza Vaccine in Children 6 Months Through 35 Months of Age (QHD00014)

December 8, 2025 updated by: Sanofi Pasteur, a Sanofi Company

Efficacy, Immunogenicity, and Safety of High-Dose Quadrivalent Influenza Vaccine Compared With Standard-Dose Quadrivalent Influenza Vaccine in Children 6 Months Through 35 Months of Age

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

Study Overview

Detailed Description

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.

Study Type

Interventional

Enrollment (Actual)

100

Phase

  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • California
      • San Diego, California, United States, 92123-1881
        • California Research Foundation Site Number : 8400008
    • Florida
      • Miami, Florida, United States, 33142
        • Acevedo Clinical Research Associates Site Number : 8400007
    • Georgia
      • Atlanta, Georgia, United States, 30322
        • Emory Childrens Center- Site Number : 8400001
    • Kansas
      • El Dorado, Kansas, United States, 67042
        • Heartland El Dorado- Site Number : 8400032
    • Kentucky
      • Bardstown, Kentucky, United States, 40004
        • Kentucky Pediatrics / Adult Research- Site Number : 8400005
    • Louisiana
      • New Orleans, Louisiana, United States, 70119
        • Velocity Clinical Research- New Orleans Site Number : 8400009
    • Ohio
      • Dayton, Ohio, United States, 45414
        • Ohio Pediatric Research- Site Number : 8400027
    • South Carolina
      • Barnwell, South Carolina, United States, 29812
        • Rainbow Pediatrics- Site Number : 8400033
    • Utah
      • Salt Lake City, Utah, United States, 84107
        • Cenexel JBR- Site Number : 8400006
      • Salt Lake City, Utah, United States, 84121
        • Foothill Family Clinic South- Site Number : 8400045

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

6 months to 2 years (Child)

Accepts Healthy Volunteers

Yes

Description

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.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: 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.
Pharmaceutical form: suspension for injection in a pre-filled syringe; route of administration: intramuscular
Active Comparator: 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.
Pharmaceutical form: suspension for injection in a pre-filled syringe; route of administration: intramuscular

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Number of Participants With Laboratory-Confirmed Influenza Illness Caused by Any Influenza Viral Types/Subtypes
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Laboratory-confirmed influenza was a positive influenza result on either polymerase chain reaction (PCR) or viral culture. An influenza-like illness (ILI) was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches).
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Number of Participants With Influenza-Like Illness Laboratory-Confirmed as Positive for Viral Strains Similar to Those Contained in the Vaccine
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Laboratory-confirmed influenza was a positive influenza result on either PCR or viral culture. An ILI was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches).
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Number of Participants With Influenza-Like Illness Laboratory-Confirmed as Positive in Participants Aged 6 Through 23 Months for Any Influenza A or B Type
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Laboratory-confirmed influenza was a positive influenza result on either PCR or viral culture. An ILI was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches).
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Number of Participants With Influenza-Like Illness Laboratory-Confirmed as Positive for Any Influenza A or B Type According to Previous Vaccination Status
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Laboratory-confirmed influenza was a positive influenza result on either PCR or viral culture. An ILI was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches).
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Number of Participants With Influenza-Like Illness Laboratory-Confirmed as Positive for Viral Strains Similar to Those Contained in the Vaccine According to Previous Vaccination Status
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Laboratory-confirmed influenza was a positive influenza result on either PCR or viral culture. An ILI was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches).
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Number of Participants With Influenza-Like Illness Laboratory-Confirmed as Positive for Any Influenza A or B Type and Associated With Acute Otitis Media (AOM)
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Laboratory-confirmed influenza was a positive influenza result on either PCR or viral culture. An ILI was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches). The AOM was based on clinical diagnosis.
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Number of Participants With Influenza-Like Illness Laboratory-Confirmed as Positive for Viral Strains Similar to Those Contained in the Vaccine and Associated With Acute Otitis Media
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Laboratory-confirmed influenza was a positive influenza result on either PCR or viral culture. An ILI was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches). The AOM was based on clinical diagnosis.
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Number of Participants With Influenza-Like Illness Laboratory-Confirmed as Positive for Any Influenza A or B Type and Associated With Acute Lower Respiratory Infection (ALRI)
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Laboratory-confirmed influenza was a positive influenza result on either PCR or viral culture. An ILI was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches). The ALRI was based on a clinical and/or x-ray diagnosis.
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Number of Participants With Influenza-Like Illness Laboratory-Confirmed as Positive for Viral Strains Similar to Those Contained in the Vaccine and Associated With Acute Lower Respiratory Infection
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Laboratory-confirmed influenza was a positive influenza result on either PCR or viral culture. An ILI was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches). The ALRI was based on a clinical and/or x-ray diagnosis.
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Number of Participants With Influenza-Like Illness Polymerase Chain Reaction-Confirmed as Positive for Viral Strains Similar to Those Contained in the Vaccine
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
The PCR-confirmed influenza was a positive influenza result on PCR. An ILI was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches).
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Number of Participants With Influenza-Like Illness Culture-Confirmed as Positive for Viral Strains Similar to Those Contained in the Vaccine
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Culture-confirmed influenza was a positive influenza result on viral culture. An ILI was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches).
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Number of Participants With Influenza-Like Illness Polymerase Chain Reaction-Confirmed as Positive for Any Influenza A or B Types
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
The PCR-confirmed influenza was a positive influenza result on PCR. An ILI was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches).
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Number of Participants With Influenza-Like Illness Culture-Confirmed as Positive for Any Influenza A or B Types
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Culture-confirmed influenza was a positive influenza result on viral culture. An ILI was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches).
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Number of Participants With Influenza-Like Illness Laboratory-Confirmed as Positive for Any Influenza A or B Types and Associated With Hospitalization
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Laboratory-confirmed influenza was a positive influenza result on either PCR or viral culture. An ILI was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches).
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Number of Participants With Influenza-Like Illness Laboratory-Confirmed as Positive for Viral Strains Similar to Those Contained in the Vaccine and Associated With Hospitalization
Time Frame: From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Laboratory-confirmed influenza was a positive influenza result on either PCR or viral culture. An ILI was occurrence of fever concurrently with at least 1 of the following symptoms: cough, wheezing, difficulty breathing, nasal congestion, rhinorrhea, pharyngitis (sore throat), otitis, vomiting, diarrhea, shivering (chills), fatigue (tiredness), headache, or myalgia (muscle aches).
From 14 days after the first vaccine administration up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 196 days
Geometric Mean Titer of Influenza Vaccine Antibodies
Time Frame: Days 0 and 56
Antibody titers were measured by hemagglutination inhibition (HAI) assay.
Days 0 and 56
Number of Participants With Seroconversion
Time Frame: Days 0 and 56
Seroconversion for participants with a pre-vaccination titer <10 [1/dilution (dil)]: Post-injection titer >=40 (1/dil) on 28 days after the last vaccination or significant increase. Seroconversion for participants with a pre-vaccination titer >=10 (1/dil): >=4-fold increase from pre- to post-injection titer on 28 days after the last vaccination. Antibody titers were measured by HAI assay.
Days 0 and 56
Number of Participants With Influenza Vaccine Antibody Titer >=10 (1/Dilution)
Time Frame: Days 0 and 56
Antibody titers were measured by HAI assay. The influenza vaccine antibody titer level assessed was >=10 (1/dil).
Days 0 and 56
Influenza Vaccine Antibody Titer Ratio
Time Frame: Days 0 and 56
Antibody titer ratio was calculated as individual antibody titer 28 days after the last vaccination (Day 56) divided by individual antibody titer at Day 0. Antibody titers were measured by HAI assay.
Days 0 and 56
Number of Participants With Influenza Vaccine Antibody Titer >=40 (1/Dilution)
Time Frame: Days 0 and 56
Antibody titers were measured by HAI assay. The influenza vaccine antibody titer level assessed was >=40 (1/dil).
Days 0 and 56
Influenza Seroneutralization (SN) Antibody Titer
Time Frame: Days 0 and 56
The antibody titers were measured by the SN method.
Days 0 and 56
Influenza Seroneutralization Antibody Titer Ratio
Time Frame: Day 56
Antibody titer ratio was calculated as fold increase in serum SN post-vaccination relative to Day 0. Antibody titers were measured by the SN method.
Day 56
Number of Participants With Influenza Seroneutralization Antibody Titer >=20 (1/Dilution), >=40 (1/Dilution) and >=80 (1/Dilution)
Time Frame: Day 56
Antibody titers were measured by the SN method. The SN antibody titer levels assessed were >=20 (1/dil), >=40 (1/dil) and >=80 (1/dil).
Day 56
Number of Participants With Influenza Seroneutralization Antibody Titer >=2 and >=4 Fold-Rise
Time Frame: Day 56
Increase of titer levels >=2 and >=4 were assessed. Antibody titers were measured by the SN method.
Day 56
Detectable Influenza Seroneutralization Antibody Titer
Time Frame: Days 0 and 56
Detectable antibody titers were >=10 (1/dil). Antibody titers were measured by the SN method.
Days 0 and 56
Anti-Neuraminidase (Anti-NA) Antibody Titer
Time Frame: Days 0 and 56
Antibody titers were measured by enzyme-linked lectin assay.
Days 0 and 56
Anti-Neuraminidase Antibody Titer Ratio
Time Frame: Day 56
Antibody titer ratio was calculated as fold increase in anti-NA antibodies post-vaccination relative to Day 0. Antibody titers were measured by enzyme-linked lectin assay.
Day 56
Number of Participants With Anti-Neuraminidase Antibody Titer >=20 (1/Dilution), >=40 (1/Dilution) and >=80 (1/Dilution)
Time Frame: Day 56
Antibody titers were measured by enzyme-linked lectin assay. Anti-NA antibody titer levels assessed were >=20 (1/dil), >=40 (1/dil) and >=80 (1/dil).
Day 56
Number of Participants With Anti-Neuraminidase Antibody Titer >=2 and >=4 Fold-Rise
Time Frame: Day 56
Increase of titer levels >=2 and >=4 were assessed. Antibody titers were measured by enzyme-linked lectin assay.
Day 56
Detectable Anti-Neuraminidase Antibody Titer
Time Frame: Days 0 and 56
Detectable antibody titers were >=10 (1/dil). Antibody titers were measured by enzyme-linked lectin assay.
Days 0 and 56
Number of Participants With Unsolicited Systemic Adverse Events (AEs) After Each Vaccine Dose Administration
Time Frame: Within 30 minutes after each vaccine administration (vaccines administered at Days 0 and 28)
An AE was any untoward medical occurrence in a clinical study participant, temporally associated with the use of study vaccine, whether or not considered related to the study vaccine. Immediate events were recorded to capture medically relevant unsolicited systemic AEs which occurred within the first 30 minutes after vaccination. An unsolicited AE was an observed AE that did not fulfill the conditions of solicited reactions, that is, pre-listed in the case report form in terms of diagnosis and onset window post-vaccination.
Within 30 minutes after each vaccine administration (vaccines administered at Days 0 and 28)
Number of Participants With Solicited Injection Site Reactions After Each Vaccine Dose Administration
Time Frame: Within 7 days after each vaccine administration (vaccines administered at Days 0 and 28)
A solicited reaction was an "expected" adverse reaction (AR) (sign or symptom) observed and reported under the conditions (nature and onset) pre-listed in the protocol and case report form, and were considered to be related to the study vaccine administered. An injection site reaction was an AR at and around the injection site of the study vaccine.
Within 7 days after each vaccine administration (vaccines administered at Days 0 and 28)
Number of Participants With Solicited Systemic Reactions After Each Vaccine Dose Administration
Time Frame: Within 7 days after each vaccine administration (vaccines administered at Days 0 and 28)
A solicited reaction was an "expected" AR (sign or symptom) observed and reported under the conditions (nature and onset) pre-listed in the protocol and case report form, and were considered to be related to the study vaccine administered. Systemic AR were all ARs that were not injection site reactions.
Within 7 days after each vaccine administration (vaccines administered at Days 0 and 28)
Number of Participants With Unsolicited Adverse Events After Each Vaccine Dose Administration
Time Frame: Within 28 days after each vaccine administration (vaccines administered at Days 0 and 28)
An AE was any untoward medical occurrence in a clinical study participant, temporally associated with the use of study vaccine, whether or not considered related to the study vaccine. An unsolicited AE was an observed AE that did not fulfill the conditions of solicited reactions, that is, pre-listed in the case report form in terms of diagnosis and onset window post-vaccination.
Within 28 days after each vaccine administration (vaccines administered at Days 0 and 28)
Number of Participants With Serious Adverse Events (SAEs) and Adverse Events of Special Interest (AESIs)
Time Frame: From first dose of study vaccine administration (Day 1) up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 210 days
An SAE was defined as any AE that at any dose resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect, or was an important medical event. An AESI (serious or non-serious) was 1 of scientific and medical concern specific to the Sponsor's study vaccine or program, for which ongoing monitoring and rapid communication by the Investigator to the Sponsor could be appropriate.
From first dose of study vaccine administration (Day 1) up to 6 months after the last vaccine administration (vaccines administered at Days 0 and 28), approximately 210 days

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Study Director: Clinical Sciences & Operations, Sanofi Pasteur, a Sanofi Company

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

September 15, 2020

Primary Completion (Actual)

June 2, 2021

Study Completion (Actual)

June 2, 2021

Study Registration Dates

First Submitted

September 3, 2020

First Submitted That Met QC Criteria

September 3, 2020

First Posted (Actual)

September 10, 2020

Study Record Updates

Last Update Posted (Estimated)

December 24, 2025

Last Update Submitted That Met QC Criteria

December 8, 2025

Last Verified

December 1, 2025

More Information

Terms related to this study

Other Study ID Numbers

  • QHD00014 (Other Identifier: Sanofi Identifier)
  • U1111-1243-5993 (Registry Identifier: ICTRP)
  • 2019-004721-24 (EudraCT Number)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

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

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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