Study With Quadrivalent Recombinant Influenza Vaccine (RIV4) in Participants 9 Through 49 Years of Age.

Study Overview
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Brief Summary
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The purpose of this study is to demonstrate the non-inferiority (NI) of the HAI immune response of RIV4 in participants aged 9 to 17 years vs participants aged 18 to 49 years and to describe the immunogenicity and safety profile of RIV4 in all participants.

Detailed Description
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The participation duration will be approximately 6 months for each participant.

Official Title
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Immunogenicity and Safety of Quadrivalent Recombinant Influenza Vaccine (RIV4) in Children and Adolescents Aged 9 to 17 Years and Adults Aged 18 to 49 Years.

Conditions
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Influenza Immunization

Intervention / Treatment
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* Biological: Quadrivalent Recombinant influenza vaccine (RIV4) season/2022-2023/NH


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged 9 to 49 years on the day of inclusion A female participant is eligible to participate if she is not pregnant or breastfeeding and one of the following conditions applies: 1) Is of non-childbearing potential. To be considered of non-childbearing potential, a female must be pre-menarche, post-menopausal for at least 1 year, or surgically sterile OR 2) Is of childbearing potential and agrees to use an effective contraceptive method or abstinence from at least 4 weeks prior to the first study intervention administration until at least 4 weeks after the last study intervention administration Assent form or informed consent form has been signed and dated by the participant (based on local regulations), and if applicable informed consent form has been signed and dated by the parent(s) or another legally acceptable representative Exclusion Criteria: Known or suspected congenital or acquired immunodeficiency, 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 trial or to a vaccine containing any of the same substances Thrombocytopenia Bleeding disorder, or receipt of anticoagulants in the 3 weeks preceding inclusion, contraindicating intramuscular vaccination based on the Investigator's judgment Personal or family history of Guillain-Barre Syndrome (GBS) Personal history of clinically significant development delay (at the discretion of the Investigator), neurologic disorder, or seizure disorder NOTE: The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.

Ages Eligible for Study
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Minimum Age: 9 Years
Maximum Age: 49 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Group 9 to 17 years old<br>Participants of 9 to 17 years old who will receive RIV4 single intramuscular (IM) injection at D01 | Biological: Quadrivalent Recombinant influenza vaccine (RIV4) season/2022-2023/NH<br>* Pharmaceutical form: Solution for injection Route of administration: intramuscular<br>* Other names: Supemtek / Flublok Quadrivalent;|
| Experimental: Group 18 to 49 years old<br>Participants of 18 to 49 years old who will receive RIV4 single intramuscular (IM) injection at D01 | Biological: Quadrivalent Recombinant influenza vaccine (RIV4) season/2022-2023/NH<br>* Pharmaceutical form: Solution for injection Route of administration: intramuscular<br>* Other names: Supemtek / Flublok Quadrivalent;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Individual Hemagglutination inhibition (HAI) titer at D29 after vaccination | Geometric Mean Titers (GMTs) of RIV4 in participants aged 9 to 17 years and participants aged 18 to 49 years | Day 29 (28 days after vaccination) | 
| Percentage of participants achieving seroconversion | Seroconversion for participants with a pre-vaccination titer lower than (<) 10 [1/dil] at D01 and a post-vaccination titer ≥ 40 [1/dil] at D29, or a pre-vaccination titer ≥ 10 [1/dil] at D1 and a ≥ 4-fold increase in post-vaccination titer at D29 | Day 29 (28 days after vaccination) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Individual Hemagglutination inhibition (HAI) titer at Day01 and at D29 after vaccination | Antibody titers are expressed as GMTs at baseline and post-baseline | Day 1 and Day 29 (28 days after vaccination) | 
| Percentage of participants with detectable antibody titers greater than or equal to (≥) 10 [1/dil] |  | Day 1 and Day 29 (28 days after vaccination) | 
| Percentage of participants with antibody titers greater than or equal to (≥) 40 [1/dil] |  | Day 1 and Day 29 (28 days after vaccination) | 
| Occurrence of immediate adverse events (AEs) | Immediate adverse events include unsolicited systemic adverse events within 30 minutes after vaccination | Within 30 minutes after vaccination | 
| Occurrence of solicited injection site reactions and systemic reactions | Adverse reactions pre-listed in the (electronic) case report book (CRB) Injection site reactions: pain, redness, swelling, hardening, bruising Systemic reactions: fever, headache, malaise, myalgia | Within 8 days after vaccination | 
| Occurrence of unsolicited AEs | AEs that other than solicited reactions | Up to 28 days after vaccination | 
| Occurrence of attended adverse event (MAAEs) |  | Up to 28 days after vaccination | 
| Occurrence of serious adverse events (SAEs) | SAEs, including adverse event of special interest (AESIs) | From Day 1 until the EoS (up to 6 months after vaccination) |