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

GMTs of anti-influenza antibodies were measured using individual hemagglutination inhibition (HAI) assay for 4 influenza virus strains: A/H1N1, A/H3N2, B/Victoria, and B/Yamagata lineages.

Time frame: Day 29

Population: Analysis was performed on the Per-protocol analysis set (PPAS)-subset of full analysis set (FAS) which included participants who received 1 dose of the study vaccine and had a post-vaccination blood sample.

Anti-influenza antibodies were measured using HAI assay for 4 influenza virus strains: A/H1N1, A/H3N2, B/Victoria, and B/Yamagata lineages. Seroconversion was defined as either a pre-vaccination titer less than (\<) 1:10 (1/dilution) at Day 1 and a post-vaccination titer greater than or equal to (\>=) 1: 40 (1/dilution) at Day 29 or a pre-vaccination titer \>= 1:10 at Day 1 and a \>= 4-fold increase in post-vaccination titer.

Time frame: Day 29

Population: Analysis was performed on the PPAS-subset of FAS which included participants who received 1 dose of the study vaccine and had a post-vaccination blood sample. Only participants with data collected for each category at Day 29 are reported.

GMTR was the ratio of the individual titers post-vaccination over pre-vaccination. The GMTs were measured using HAI assay for 4 influenza virus strains: A/H1N1, A/H3N2, B/Victoria, and B/Yamagata lineages.

Time frame: On Days 1 and 29

Population: Analysis was performed on the PPAS-subset of FAS which included participants who received 1 dose of the study vaccine and had a post-vaccination blood sample. Only participants with data collected for each category on Days 1 and Day 29 are reported.

GMTs of anti-influenza antibodies were measured using HAI assay for 4 influenza virus strains: A/H1N1, A/H3N2, B/Victoria, and B/Yamagata lineages.

Time frame: Pre-vaccination on Day 1

Population: Analysis was performed on the PPAS-subset of FAS which included participants who received 1 dose of the study vaccine and had a post-vaccination blood sample. Only participants with data collected for each category at Day 1 are reported.

An AE was any untoward medical occurrence in a clinical investigation participant temporally associated with the use of study intervention, whether or not considered related to the study intervention. An unsolicited AE was an observed AE that did not fulfill the conditions of solicited reactions, that is, prelisted in the CRF in terms of diagnosis and/or onset window post-vaccination. All participants were observed for 30 minutes after vaccination, and any unsolicited AEs occurred during that time were recorded as immediate unsolicited AEs.

Time frame: Within 30 minutes post-vaccination on Day 1

Population: Analysis was performed on the Safety analysis set which included participants who received 1 dose of the study vaccine.

An MAAE was a new onset or a worsening of a condition that prompted the participant or participant's parent/guardian to seek unplanned medical advice at a physician's office or emergency department.

Time frame: From Day 1 up to 28 days post-vaccination (up to Day 29)

Population: Analysis was performed on the Safety analysis set which included participants who received 1 dose of the study vaccine.

An SAE was any untoward medical occurrence 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 was defined as one of scientific and medical concern specific to the Sponsor's study intervention, events for which ongoing monitoring and rapid communication by the investigator to the sponsor was done.

Time frame: From Day 1 up to 6 months post-vaccination, 181 days

Population: Analysis was performed on the Safety analysis set which included participants who received 1 dose of the study vaccine.

A solicited reaction was an expected adverse reaction (sign or symptom) observed and reported under the conditions (nature and onset) prelisted in the protocol and CRF and considered as related to the study intervention administered. An injection site reaction was an AR at and around the injection site and were commonly inflammatory reactions. Solicited systemic reactions were systemic AEs and those occurring during the specified collection period were always considered related to the intervention even if there was evidence of alternative etiology.

Time frame: From Day 1 up to 7 days post-vaccination (up to Day 8)

Population: Analysis was performed on the Safety analysis set which included participants who received 1 dose of the study vaccine. Number of participants analyzed signifies those participants with data collected for this outcome measure and number analyzed signifies those participants with data collected for specified category.

An AE was any untoward medical occurrence in a clinical investigation participant temporally associated with the use of study intervention, whether or not considered related to the study intervention. An unsolicited AE was an observed AE that did not fulfill the conditions of solicited reactions, that is, prelisted in the CRF in terms of diagnosis and/or onset window post-vaccination.

Time frame: From Day 1 up to 28 days post-vaccination (up to Day 29)

Population: Analysis was performed on the Safety analysis set which included participants who received 1 dose of the study vaccine.

Antibody titers were measured using HAI assay for 4 influenza virus strains: A/H1N1, A/H3N2, B/Victoria, and B/Yamagata lineages. Percentage of participants with antibody titers \>=10 and \>=40 against influenza vaccine antibodies at Day 1 and Day 29 were reported in this outcome measure.

Time frame: On Days 1 and 29

Population: Analysis was performed on the PPAS-subset of FAS which included participants who received 1 dose of the study vaccine and had a post-vaccination blood sample. Only participants with data collected for each category on Days 1 and 29 are reported.