HI antibody titers against H1N1, H3N2, B/Victoria, and B/Yamagata Influenza vaccine strains 29 days after the administration of HD quadrivalent seasonal influenza vaccine as measured by HI assay were reported.

Per protocol influenza immunogenicity (PPII) analysis set included all randomized participants who received first study vaccination (ExPEC9V in combination with HD quadrivalent seasonal influenza vaccine for CoAd group and HD quadrivalent seasonal influenza vaccine alone for the Control group) for whom immunogenicity data were available for at least 1 of the influenza strains in vaccine. N (Overall number of participants analyzed) signifies participants evaluable for this outcome measure (OM).

Antibody titers to vaccine O-serotype antigens (O1A, O2, O4, O6A, O15, O16, O18A, O25B, and O75) as determined by ECL based Immunoassay 29 days after administration of ExPEC9V on Day 1 in CoAd group and on Day 30 in Control group were reported.

Per protocol ExPEC immunogenicity (PPEI) analysis set included all randomized participants who received ExPEC9V in combination with a HD quadrivalent seasonal influenza vaccine for the CoAd group and ExPEC9V alone for the control group and for whom O-antigen immunogenicity data were available for at least one E. coli serotype.

Seroconversion was defined for each of the 4 influenza vaccine strains as 1) HI titer greater than or equal to (>=) 1:40 in participants with a pre-vaccination HI titer of less than (<) 1:10, or 2) a >=4-fold HI titer increase in participants with a pre-vaccination HI titer of >=1:10.

PPII analysis set included all randomized participants who received first study vaccination (ExPEC9V in combination with HD quadrivalent seasonal influenza vaccine for CoAd group and HD quadrivalent seasonal influenza vaccine alone for Control group) and for whom immunogenicity data were available for at least 1 of the influenza strains in vaccine. Here, N (Overall number of participants analyzed) signifies participants evaluable for this outcome measure.

Seroprotection was defined for each of the 4 influenza vaccine strains as HI titer >=1:40 at 29 days after the administration of a HD quadrivalent seasonal influenza vaccine.

PPII analysis set included all randomized participants who received first study vaccination (ExPEC9V in combination with HD quadrivalent seasonal influenza vaccine for CoAd group and HD quadrivalent seasonal influenza vaccine alone for Control group) and for whom immunogenicity data were available for at least 1 of the influenza strains in vaccine. Here, N (Overall number of participants analyzed) signifies participants evaluable for this outcome measure.

An AE was any untoward medical occurrence in a clinical study participant administered a pharmaceutical (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the study vaccination. Solicited local AEs were used to assess the reactogenicity of the study vaccine and were pre-defined local (injection site) events for which participants were to be specifically questioned and which were noted by participants in their participant diary for 14 days post vaccination (day of vaccination and the subsequent 14 days). Solicited local AEs were injection site pain or tenderness, erythema and swelling at the study vaccine injection site.

FAS included all participants who received at least one study vaccination, regardless of the occurrence of protocol deviations and vaccine type (HD quadrivalent seasonal influenza vaccine, ExPEC9V, or placebo). Here, n (number analyzed) signifies participants evaluated at specified timepoints.

An AE was any untoward medical occurrence in a clinical study participant administered a pharmaceutical (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the study vaccination. Solicited systemic AEs were used to assess the reactogenicity of the study vaccine and were pre-defined systemic events for which participants were to be specifically questioned and which were noted by participants in their participant diary for 14 days post vaccination (day of vaccination and the subsequent 14 days). Solicited systemic AEs included fever (body temperature >=100.4 degree Fahrenheit), fatigue, headache, nausea, myalgia, and fever.

FAS included all participants who received at least one study vaccination, regardless of the occurrence of protocol deviations and vaccine type (HD quadrivalent seasonal influenza vaccine, ExPEC9V, or placebo). Here, n (number analyzed) signifies participants evaluated at specified timepoints.

Percentage of participants with unsolicited AEs for 29 days after each vaccination was reported. An AE was any untoward medical occurrence in a clinical study participant administered a pharmaceutical (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the study vaccination. Unsolicited AEs were all AEs for which the participant was not specifically questioned in the participant diary.

FAS included all participants who received at least one study vaccination, regardless of the occurrence of protocol deviations and vaccine type (HD quadrivalent seasonal influenza vaccine, ExPEC9V, or placebo). Here, n (number analyzed) signifies participants evaluated at specified timepoints.

MAAEs were defined as AEs with medically-attended visits including hospital, emergency room, urgent care clinic, or other visits to or from medical personnel for any reason. An AE was any untoward medical occurrence in a clinical study participant administered a pharmaceutical (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the study vaccination.

FAS included all participants who received at least one study vaccination, regardless of the occurrence of protocol deviations and vaccine type (HD quadrivalent seasonal influenza vaccine, ExPEC9V, or placebo).

Percentage of participants with SAEs from vaccination 1 to until 6 months after vaccination 2 was reported. An AE was any untoward medical occurrence in a clinical study administered a medicinal (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the study vaccine. An SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly/birth defect; suspected transmission of any infectious agent via a medicinal product or medically important.

FAS included all participants who received at least one study vaccination, regardless of the occurrence of protocol deviations and vaccine type (HD quadrivalent seasonal influenza vaccine, ExPEC9V, or placebo).

Antibody titers to vaccine O-serotype antigens (O1A, O2, O4, O6A, O15, O16, O18A, O25B, and O75) and EPA as determined by multiplex ECL-based immunoassay were reported.

PPEI analysis set: who received ExPEC9V with HD quadrivalent seasonal influenza vaccine (CoAd) and ExPEC9V alone (control), with O-antigen immunogenicity data available for atleast one E. coli serotype. N (Overall number of participants analyzed): participants evaluable for this OM, n (number analyzed): participants analyzed at specified timepoints. n=0: data was not planned to be collected and analyzed for Control group at Day 1 as participants did not receive ExPEC9V vaccine on Day 1.

Opsonophagocytic antibody titers to vaccine O-serotype antigens O1A, O2, O4, O6A, O15, O16, O18A, O25B, and O75 as determined by MOPA were reported.

PPEI analysis set included all randomized participants who received ExPEC9V in combination with a HD quadrivalent seasonal influenza vaccine for the CoAd group and ExPEC9V alone for the control group and for whom O-antigen immunogenicity data were available for at least one E. coli serotype. Here, N (Overall number of participants analyzed) signifies participants evaluable for this outcome measure and n (number analyzed) signifies participants evaluated for specified categories.

Opsonophagocytic antibody titers to vaccine O-serotype antigens (O1A, O2, O4, O6A, O15, O16, O18A, O25B, and O75) as determined by MOPA were reported.

PPEI analysis set included all randomized participants who received ExPEC9V in combination with a HD quadrivalent seasonal influenza vaccine for the CoAd group and ExPEC9V alone for the control group and for whom O-antigen immunogenicity data were available for at least one E. coli serotype. Here, N (Overall number of participants analyzed) signifies participants evaluable for this outcome measure and n (number analyzed) signifies participants evaluated for specified categories.

Antibody titers to vaccine O-serotype antigens (O1A, O2, O4, O6A, O15, O16, O18A, O25B, and O75) in participants with and without history of UTI at enrollment as determined by multiplex ECL-based immunoassay were reported.

Analysis population included participants with and without history of UTI at enrollment. Here, N (Overall number of participants analyzed) signifies participants evaluable for this OM and n (number analyzed) signifies participants evaluated for specified categories.

Antibody titers to vaccine O-serotype antigens (O1A, O2, O4, O6A, O15, O16, O18A, O25B, and O75) in participants with and without history of UTI at enrollment as determined by multiplex ECL-based immunoassay were reported.

Analysis population included participants with and without history of UTI at enrollment. Here, N (Overall number of participants analyzed) signifies participants evaluable for this OM and n (number analyzed) signifies participants evaluated for specified categories.

Opsonophagocytic antibody titers to vaccine O-serotype antigens (O1A, O2, O4, O6A, O15, O16, O18A, O25B, and O75) in participants with and without history of UTI at enrollment as determined by MOPA were reported.

Analysis population included participants with and without history of UTI at enrollment. Here, N (Overall number of participants analyzed) signifies participants evaluable for this OM and n (number analyzed) signifies participants evaluated for specified categories.

Opsonophagocytic antibody titers to vaccine O-serotype antigens (O1A, O2, O4, O6A, O15, O16, O18A, O25B, and O75) in participants with and without history of UTI at enrollment as determined by MOPA were reported.

Analysis population included participants with and without history of UTI at enrollment. Here, N (Overall number of participants analyzed) signifies participants evaluable for this OM and n (number analyzed) signifies participants evaluated for specified categories.