Treatment Trials

668 Clinical Trials for Various Conditions

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RECRUITING
Evaluating the Dose, Safety, Tolerability, and Immunogenicity of Mosaic Hexavalent Influenza Vaccine VRCFLUMOS0116-00-VP (FluMos-v2) With and Without ALFQ Adjuvant in Healthy Adults
Description

Background: Vaccines help the body learn to fight infections. Some vaccines are combined with adjuvants, which are added substances that make vaccines work better. FluMos-v2 is an experimental flu vaccine; ALFQ is an experimental adjuvant. Objective: To test FluMos-v2, with and without the ALFQ adjuvant, in healthy adults. Eligibility: Healthy adults aged 18 to 50 years. They must have received at least one flu vaccine from the 2020-21 season through the 2023-24 flu season. They must also agree not to receive the licensed 2025-26 flu vaccine. Design: Participants will have 12 clinic visits over 15 months. Participants will be screened. They will have a physical exam and blood tests. On 2 visits, about 4 months apart, participants will receive a vaccination. The shots will be given into the muscle of the upper arm. They will get a follow-up call the day after each shot. They will keep a daily diary for 7 days; they will record their temperature and any other symptoms they feel after each shot. All clinic visits will include collection of blood, saliva, and nasal secretions. If participants develop flu symptoms (such as fever, runny nose, sore throat), they will be asked to come to the clinic. About 2 weeks after each vaccination, participants may opt to undergo apheresis: Blood will be taken from the body through a needle inserted into one arm. The blood will pass through a machine that separates out the white blood cells. The remaining blood will be returned to the body through a needle in the other arm.

ACTIVE_NOT_RECRUITING
Study of a Combination Vaccine Comprised of Different Recombinant Spike Antigen Levels of a Matrix-M Adjuvanted Recombinant COVID-19 Vaccine and Recombinant Influenza Vaccine in Adult Participants 50 Years of Age and Older
Description

Study VBT00002 is planned to be a Phase 1/2, randomized, modified double-blind, active-controlled, multi-center study to be conducted in approximately 980 adults aged 50 years and older in the United States. The purpose of the study is to assess the safety and immunogenicity of recombinant influenza vaccine (RIV) + adjuvanted recombinant COVID-19 vaccine (rC19) vaccine comprised of RIV combined with different recombinant Spike (rS) antigen levels of rC19 compared to RIV alone, rC19 (dose 1) alone, and RIV and rC19 (dose 1) (coadministered in opposite arms). Placebo will be coadministered in the RIV alone, rC19 (dose 1) alone, and RIV + rC19 study groups to control for the number of injections and to maintain observer blinding. Thus, each participant will receive two injections at enrollment, one in each deltoid muscle. Study details include: * The study duration will be approximately 12 months * Study intervention will be administered via a single intramuscular (IM) injection into the right and left deltoid muscles on Day(D) 01 * Dose escalation with sequential enrollment (sentinel cohort followed by main cohort for a given dose) * The visit frequency for participants will be D01 and D30, and D09-D366 (telephone call) Number of Participants: Approximately 980 participants are expected to be randomized.

ACTIVE_NOT_RECRUITING
Study of a Combination Vaccine Comprised of Different Recombinant Spike Antigen Levels of a Matrix-M Adjuvanted Recombinant COVID-19 Vaccine and High-Dose Inactivated Influenza Vaccine in Adult Participants 50 Years of Age and Older
Description

Study VBT00001 is planned to be a Phase 1/2, randomized, modified double-blind, active-controlled, multi-center study to be conducted in approximately 980 adults aged 50 years and older in the United States. The purpose of the study is to assess the safety and immunogenicity of IIV-HD (high-dose inactivated influenza vaccine) + rC19 (adjuvanted recombinant COVID-19 vaccine) vaccine comprised of IIV-HD combined with different recombinant Spike (rS) antigen levels of rC19 compared to IIV-HD alone, rC19 (dose 1) alone, and IIV-HD and rC19 (dose 1) (coadministered in opposite arms). Placebo will be coadministered in the IIV-HD alone, rC19 (dose 1) alone, and IIV-HD + rC19 study groups to control for the number of injections and to maintain observer-blinding. Thus, each participant will receive two injections at enrollment, one in each deltoid muscle. Study details include: * The study duration will be approximately 12 months * Study intervention will be administered via a single intramuscular (IM) injection into the right and left deltoid muscles on D01 * Dose escalation with sequential enrollment (sentinel cohort followed by main cohort for a given dose) * The visit frequency will be D01, D09 (telephone call), D30, D182 (telephone call), and D366 (telephone call) Number of Participants: Approximately 980 participants are expected to be randomized.

ACTIVE_NOT_RECRUITING
Study to Evaluate Immunogenicity and Safety of a High-Dose Influenza Vaccine in Adults 50 Through 64 Years of Age
Description

The purpose of this study is to evaluate Immunogenicity and Safety of a High-Dose (HD) Influenza Vaccine (IV) in Adults 50 through 64 Years of Age.

Conditions
ACTIVE_NOT_RECRUITING
Text4Vax: Text Message Reminders for Pediatric COVID-19 and Influenza Vaccines 2024-25 Season
Description

This multi-site study assesses the impact of text message reminders on the receipt of COVID-19 and influenza text message reminders takes place primarily in practices from the American Academy of Pediatrics (AAP) Pediatric Research in Office Settings (PROS) network.

ACTIVE_NOT_RECRUITING
A Study of mRNA-1010 Compared With a Licensed Influenza Vaccine in Adults ≥50 Years of Age
Description

The primary objectives of this study are to evaluate the safety and reactogenicity of mRNA-1010, and to evaluate relative vaccine efficacy (rVE) of mRNA-1010 versus an active comparator against reverse transcription polymerase chain reaction (RT-PCR)-confirmed protocol-defined influenza-like illness (ILI) caused by any influenza A or B strains.

ACTIVE_NOT_RECRUITING
Characterizing Late-season Influenza Vaccine Responses to Compare the 2023 and 2024 Vaccine Formulations
Description

Every 1-2 years, the seasonal influenza vaccine composition changes to include updated viruses, yet the precise effects of updating the vaccine remain understudied. Since the vaccine formulation for each season (with a season defined as starting in July and ending the following June) expires on June 30, vaccine formulations cannot be compared head-to-head. Thus, the 2023 and 2024 vaccines have only been compared by analyzing people given the former vaccine in the fall of 2023 and people given the latter vaccine in the fall of 2024, and baseline repertoires may have greatly changed over the course of that year. To that end, the investigators will vaccinate a cohort with the 2023 influenza vaccine between May-June 2024, in order to compare responses between individuals receiving the 2023 vaccine last fall, the 2023 vaccine late in the season (this cohort), and the 2024 vaccine next fall. The investigators will further assess whether the late-season 2023 vaccine primed this cohort to respond better to the standard 2024 vaccine with standard timing (vaccine administered around September-October).

Conditions
ACTIVE_NOT_RECRUITING
A Clinical Study to Investigate the Safety and Immunogenicity in Relation to Product Attributes of mRNA-1083 (Severe Acute Respiratory Syndrome Coronavirus 2 [SARS-CoV-2] and Influenza Vaccine)
Description

The purpose of this study is to evaluate the safety, reactogenicity, and immunogenicity in relation to the product attributes of mRNA-1083 vaccine when administered as a single intramuscular (IM) injection in adults ≥50 to \<65 years of age.

RECRUITING
A Study to Evaluate the Intratumoral Influenza Vaccine Administration in Patients With Breast Cancer
Description

This Phase 1 study will assess the safety and efficacy (usefulness) of administering 2 doses of seasonal flu vaccine directly into breast cancer tissue (primary tumor), and will study the tumor and whole body response to the vaccine. If the tumor is palpable (able to fee by touch), the vaccine will be administered by a Surgeon/oncologist in the outpatient floor - both experienced and trained. If not palpable, the procedure will be done via guided Ultrasound by our Breast Radiologist -- both experienced and trained. Women with triple-negative (TNBC) and HER2+ types of breast cancer will be eligible for enrollment. Up to 18 subjects may be enrolled at Rush. Successive groups of 3 subjects per breast cancer type will be given increasing doses of vaccine. There are 3 potential dosing groups (half-dose, full dose, and high dose). Blood, stool (optional), and tumor tissue samples will be collected and tested. The active participation period is from one week prior to starting chemotherapy through three months post surgery.

COMPLETED
A Study of 9-valent Extraintestinal Pathogenic Escherichia Coli Vaccine (ExPEC9V) and High-dose Quadrivalent Influenza Vaccine, With and Without Co-administration, in Adults Aged 65 Years or Older
Description

The purpose of this study is to show that high-dose quadrivalent seasonal influenza vaccine (HD QIV) given together with 9-valent extraintestinal pathogenic Escherichia coli vaccine (ExPEC9V) does not induce lower antibody response against each of the 4 influenza vaccine strains, as compared to HD QIV given alone and further show that ExPEC9V given together with HD QIV does not induce lower antibody response against each of the vaccine O-serotype antigens, as compared to ExPEC9V given alone.

COMPLETED
A Study of mRNA-1083 (SARS-CoV-2 and Influenza) Vaccine in Healthy Adult Participants, ≥50 Years of Age
Description

The purpose of this study is to evaluate the immunogenicity, safety, and reactogenicity of mRNA-1083 as compared with active control, co-administered licensed influenza and severe acute respiratory syndrome coronavirus 2 (SARS CoV 2) vaccines, in 2 independent age-group sub-study cohorts, healthy adults 65 years and older (Cohort A) and healthy adults 50 to \<65 years of age (Cohort B).

COMPLETED
Patient Portal Flu Vaccine Reminders (RCT 6)
Description

This trial is taking place in Los Angeles, CA at 21 clinics within the UCLA Health System. The study design is a 3 arm randomized trial. Patients will be randomized into 1) receiving portal based reminder messages with a video from their PCP encouraging them to receive the influenza vaccine, 2) portal-based reminder messages with an infographic with the image of their PCP encouraging them to receive the influenza vaccine, or 3) the control group. Patients randomized to the intervention arms will receive reminders if they are due for influenza vaccine. Despite the Advisory Committee on Immunization Practices (ACIP) recommendation in 2010 that all people above 6 months of age should receive an annual flu vaccine, vaccination rates remain low: at 6m-4.9 yrs. (70%), 5-17.9 yrs. (56%), 18-64.9 yrs. (38%), and \>65 yrs. (63%). The investigators will assess the effectiveness of MyChart R/R video messages and infographic messages as compared to the standard of care control (Health system messages).

ACTIVE_NOT_RECRUITING
Trial to Evaluate the Safety, Tolerability, and Immunogenicity of a Mosaic Hexavalent Influenza Vaccine VRC-FLUMOS0116-00-VP (FluMos-v2) in Healthy Adults
Description

Background: Influenza (flu) virus causes 3 to 5 million cases of severe illness and up to 650,000 deaths per year worldwide. Current vaccines work well against single strains of flu virus. But no single vaccine works well against all flu viruses that can cause illness. Objective: To test an experimental flu vaccine (FluMos-v2) in healthy adults. Eligibility: Healthy adults aged 18 to 50 years. Design: Participants will have 11 clinic visits in 10 months. They must agree not to get a licensed flu vaccine while taking part in this study. FluMos-v2 will be given with a needle injected into a muscle in the upper arm. Participants will receive a follow-up phone call the following day. Participants will be given a diary card, a ruler, and a thermometer. They will take their temperature every day for 7 days after receiving the shot. They will measure any skin changes at the injection site. They will record their findings and how they feel. Participants will receive a second FluMos-v2 shot after 4 months. They will repeat the other follow-up steps. Participants will have 9 other clinic follow-up visits. Blood will be drawn at each visit. Participants should also come to the clinic if they develop flu-like symptoms during the study. Participants may opt for an apheresis 2 weeks after each shot: Blood will be removed through a needle in the vein of 1 arm. The blood will run through a machine that separates out the white blood cells. The remaining blood is returned through a needle in the other arm.

Conditions
RECRUITING
High vs.Standard Dose Influenza Vaccine in Pediatric Solid Organ Transplant (SOT) Recipients
Description

Influenza virus is a significant pathogen in pediatric solid organ transplant (SOT) recipients. However, these individuals respond poorly to standard-dose (SD) inactivated influenza vaccine (IIV). Recent studies have investigated two strategies to overcome poor immune responses in SOT recipients: (1) administration of high-dose (HD)-IIV compared to SD-IIV and (2) two doses of SD-IIV compared to one dose of SD-IIV in the same influenza season. One study compared HD-IIV vs. SD-IIV in adult SOT recipients and noted that HD-IIV was safe and more immunogenic; however, the median post-transplant period was 38 months. A phase I pediatric study comparing a single dose of HD-IIV vs. SD-IIV was safe with higher immunogenicity, but the study was limited by small sample size and median post-transplant vaccine administration was 26 months. In another phase II trial of adult SOT recipients, two doses of SD-IIV one month apart compared to one-dose of SD-IIV revealed modestly increased immunogenicity when given at a median of 18 months post-transplant. Therefore, these studies lack both evaluation in the early post-transplant period and substantive pediatric populations. Additionally, the administration of two-doses of HD-IIV in the same influenza season has not been evaluated in pediatric SOT recipients. Thus, the optimal immunization strategy for pediatric SOT recipients less than 24 months post-transplant is unknown. In addition, immunologic predictors and correlates of influenza vaccine immunogenicity in pediatric SOT recipients have not been well-defined. The central hypothesis of our proposal is that pediatric SOT recipients 1-23 months post-transplant who receive two doses of HD-quadrivalent inactivated influenza vaccine (QIV) will have similar safety but higher Hemagglutination Inhibition (HAI) geometric mean titers (GMTs) to influenza antigens compared to pediatric SOT recipients receiving two doses of SD-QIV.

COMPLETED
A Clinical Study to Evaluate an Experimental Universal Influenza Vaccine, INFLUENZA G1 mHA, in Healthy Adults
Description

The primary purpose of this study is to evaluate safety/ reactogenicity of INFLUENZA G1 mini-hemagglutinin stem-derived protein vaccine antigen (mHA), with or without Al(OH)3 adjuvant, in healthy adults greater than or equal to (\>=) 18 to less than or equal to (\<=) 45 years of age.

COMPLETED
Study to Evaluate Immunogenicity, Safety and Tolerability of Adjuvanted and Non-Adjuvanted H2N3 Influenza Vaccines in Adults
Description

This Phase 1, randomized, observer-blind, dose-ranging clinical study is evaluating 6 different formulations of MF59-adjuvanted and non-adjuvanted H2N3 influenza vaccine. Approximately 600 healthy adult subjects are to be randomized into 1 of 6 possible treatment groups with 100 subjects per group, stratified by age group (born after or before 1968). Each subject will receive an influenza vaccine injection on Day 1 and Day 22. Subjects will be followed up for approximately 12 months after the second vaccine injection. The primary immunogenicity analysis is based on the Day 1, Day 8, Day 22, Day 29, and Day 43 serology data. The primary safety analysis is based on solicited local and systemic adverse events (AEs) reported within 10 days after each vaccination, unsolicited AEs reported within 3 weeks after each vaccination, and serious AEs (SAEs), medically attended AEs (MAAEs), AEs leading to withdrawal from the study, and AEs of special interest (AESIs) reported throughout the study.

COMPLETED
Study to Evaluate Safety and Immunogenicity of Different Priming and Booster Regimens With Adjuvanted H5N8 and/or H5N6 Influenza Vaccine in Adults
Description

This Phase 2, randomized, observer-blind clinical study is evaluating 3 different priming and booster regimens with MF59-adjuvanted H5N8 and/or H5N6 cell culture-derived influenza vaccine (aH5N8c; aH5N6c). Approximately 480 healthy adult subjects are to be randomized into 1 of 3 possible treatment groups, stratified by age group (18-64 years and ≥65 years) and by poultry worker status (yes/no). Each subject will receive a priming influenza vaccine injection on Day 1 and Day 22 and a booster vaccination on Day 202. Subjects will be followed up for approximately 6 months after the booster injection. The primary immunogenicity analysis is based on antibody responses against H5N8 and H5N6 as measured by hemagglutination inhibition (HI) assay on Day 1, Day 22, Day 29, Day 43, Day 202, Day 209 (H5N8 only), and Day 223.

COMPLETED
This Study Intends to Describe the Characteristics of Patients Given the Pfizer-BioNTech Bivalent mRNA COVID-19 Vaccine and Any Commercially Available Influenza Vaccines at the Same Time Versus at Different Times.
Description

This study intends to describe the characteristics of patients given the Pfizer-BioNTech bivalent mRNA COVID-19 vaccine and any commercially available influenza vaccines at the same time versus at different times.

COMPLETED
PROmotion of FLU Vaccine Uptake in the Emergency Department - PROFLUVAXED
Description

The goal of this research is to increase influenza vaccine acceptance and uptake in vulnerable populations whose primary (and often only) health care access occurs in emergency departments (ED Usual Source of Care Patients). Toward this goal, the investigators will conduct one on one interviews and focus groups with ED Usual Source of Care Patients and community partners and produce trusted messaging informational platforms (PROmotion of FLU VA(X)ccination in the Emergency Department - PROFLUVAXED) that will address barriers to flu vaccination, especially vaccine hesitancy. The investigators will then conduct a cluster-randomized, controlled trial of PROFLUVAXED platforms in six EDs to determine whether their implementation is associated with greater flu vaccine acceptance and uptake in ED Usual Source of Care Patients.

COMPLETED
Study of mRNA-1010 Seasonal Influenza Vaccine in Adults
Description

This study includes 3 parts: Parts A, B, and C. The purpose of this study is to evaluate the immunogenicity and safety of mRNA-1010 seasonal influenza vaccine in adults.

COMPLETED
A Study of mRNA-1011.1, mRNA-1011.2, and mRNA-1012.1 Candidate Seasonal Influenza Vaccines in Healthy Adults
Description

The purpose of this study is to measure the safety and the immune response to 3 next-generation influenza vaccine candidates (mRNA-1011.1, mRNA-1011.2, and mRNA-1012.1) compared with influenza vaccine candidate mRNA-1010 controls in healthy adult participants.

RECRUITING
Seasonal Influenza Vaccine High Dose Boosting in Solid Organ Transplant Recipients
Description

In solid organ transplant (SOT) the receipt of influenza vaccine in an influenza season is associated with decreased disease severity as demonstrated by the presence of pneumonia and ICU admissions. Different strategies have been assessed to optimize vaccine efficacy and immunogenicity of the influenza vaccine in the solid organ transplant recipient (SOTR). The primary objective of the study is to evaluate the immunogenicity of 2 doses of the high dose influenza vaccine utilizing neutralizing antibody assays. A control group receiving 1 HD influenza vaccine will be included.

COMPLETED
A Study of mRNA-1010 Seasonal Influenza Vaccine in Adults 50 Years Old and Older
Description

The purpose of this study is to evaluate the safety and efficacy of mRNA-1010 in preventing seasonal influenza in adults 50 years and older.

COMPLETED
Patient Portal Flu Vaccine Reminders_RCT 5 (LADHS)
Description

This trial is taking place in Los Angeles, CA at clinics within the Los Angeles Department of Health clinics. The study design is a comparative effectiveness trial design. Patients will be randomized into 1) receiving enhanced texting with a callback by a trained call-center staff member to schedule a vaccine visit if the patient presses "1" in response to the text, 2) receiving enhanced bidirectional texting with a texting response from a trained call-center staff member who will help the patient schedule a vaccine visit through a series of back-and-forth texts, or 3) standard text reminders (control group). Patients in all arms will receive reminders if they are due for influenza vaccine. Despite the Advisory Committee on Immunization Practices (ACIP) recommendation in 2010 that all people above 6 months of age should receive an annual flu vaccine, vaccination rates remain low: at 6m-4.9 yrs. (70%), 5-17.9 yrs. (56%), 18-64.9 yrs. (38%), and \>65 yrs. (63%). The investigators will assess the effectiveness of enhanced text R/R messages as compared to the standard of care control (standard text reminders).

COMPLETED
A Study to Evaluate the Safety, Tolerability, and Immunogenicity of V116 When Administered Concomitantly With Influenza Vaccine in Adults 50 Years of Age or Older (V116-005, STRIDE-5)
Description

This a study of V116 in adults ≥50 years of age who concomitantly received Influenza vaccine. The primary objectives of this study are to evaluate the safety, tolerability, and immunogenicity of V116 when administered concomitantly with Quadrivalent Influenza Vaccine (QIV) compared with V116 administered sequentially with QIV. The primary hypotheses state that immune responses to V116 and to QIV are non-inferior when administered concomitantly as compared with sequential administration as measured by serotype-specific opsonophagocytic activity (OPA) for V116 and hemagglutination inhibition (HAI) geometric mean titers (GMTs) for QIV, at 30 days postvaccination.

COMPLETED
Patient Portal Flu Vaccine Reminders (5)
Description

This trial is taking place in Los Angeles, CA at clinics within the UCLA Health System. The study design is a 2x2 nested factorial design. Patients will be randomized into 1) receiving text based reminder messages with direct scheduling link, 2) portal-based reminder messages with direct scheduling link, or 3) the control group. Patients randomized to the intervention arms will receive reminders if they are due for influenza vaccine. Nested within the portal reminder arm, we will have two additional components for which patients will be randomized separately: 1. A pre-commitment prompt, asking patients which time (September, October, November or December) and which place (UCLA, pharmacy, workplace or school, or other) they plan to get their Influenza vaccine with tailored monthly messages based on responses (pre-commitment message with tailored recall messages with direct scheduling vs. standard portal reminders with direct scheduling). 2. A pre-appointment reminder encouraging patients to ask for their influenza vaccine at their upcoming appointment (pre-appointment reminder encouraging influenza vaccination vs. standard pre-appointment reminder not mentioning influenza vaccination) Nested within the text message reminder arm, we will have one additional component for which patients will be randomized separately: 1) A pre-appointment reminder encouraging patients to ask for their influenza vaccine at their upcoming appointment (pre-appointment reminder encouraging influenza vaccination vs. standard pre-appointment reminder not mentioning influenza vaccination) Despite the Advisory Committee on Immunization Practices (ACIP) recommendation in 2010 that all people above 6 months of age should receive an annual flu vaccine, vaccination rates remain low: at 6m-4.9 yrs. (70%), 5-17.9 yrs. (56%), 18-64.9 yrs. (38%), and \>65 yrs. (63%). The investigators will assess the effectiveness of MyChart R/R messages and text R/R messages as compared to the standard of care control (no messages).

RECRUITING
A Deep Longitudinal Analysis of Next Generation Influenza Vaccines in Older Adults
Description

This is a prospective, single-arm study designed to understand the mechanisms that lead to a loss of response to influenza vaccine in older adults. The investigators will recruit and longitudinally follow a cohort of 75 older adults (65 years and older) who will receive three different influenza vaccines over three annual influenza seasons. Blood samples will be collected from the participants at sixteen study visits over three years. Nasal swab and stool samples will also be collected from participants at seven time-points across the study period. The study is not designed to assess safety or tolerability of the influenza vaccines administered as part of this study.

TERMINATED
Comparison of Recombinant Influenza Vaccine Versus Standard Egg-Based Inactivated Influenza Vaccine in Adults 18-64 Years
Description

This randomized, active comparator trial will compare the clinical efficacy of recombinant influenza vaccine (RIV) to standard-dose egg-based inactivated influenza vaccine (SD IIV) among adults aged 18-64 years. The primary study hypothesis is that the clinical efficacy of RIV is superior to that of SD IIV to prevent and attenuate influenza-like illness (ILI)-associated influenza virus infection. Relative efficacy will be assessed by comparing rates of ILI-associated reverse transcription polymerase chain reaction (RT-PCR)-confirmed influenza virus infection and measures of infection and illness attenuation among participants who receive RIV versus SD IIV. A secondary hypothesis is that humoral and cell-mediated immune responses to RIV are superior to responses to SD IIV. Relative immunogenicity will be assessed by comparing markers of humoral and cell-mediated immune responses post-vaccination among a subset of participants who receive RIV versus SD IIV.

TERMINATED
Study With Quadrivalent Recombinant Influenza Vaccine (RIV4) Compared With Egg-Based Quadrivalent Influenza Vaccine (IIV4) in Participants Aged 3 to 8 Years
Description

The purpose of this study was to demonstrate the non-inferior HAI immune response of quadrivalent recombinant influenza vaccine (RIV4) vs licensed Egg-Based Quadrivalent Influenza Vaccine (IIV4) for the 4 strains based on the egg-derived antigen in all participants aged 3 to 8 years and to describe the immunogenicity and safety profile of RIV4 compared to IIV4 in participants aged 3 to 8 years.

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

The purpose of this study was 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.