Trial Outcomes & Findings for A Study to Evaluate Safety and Immunogenicity of the ExPEC4V Clinical Trial Material After a Single Intramuscular Dose and a Second Dose 6 Months Later in Healthy Participants Aged 18 Years and Older (NCT NCT03500679)

Results Overview

An AE is any untoward medical occurrence in a clinical study participant administered a medicinal (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the study vaccine. An AE can therefore be any unfavorable and unintended sign (including an abnormal finding), symptom, or disease temporally associated with the use of a medicinal (investigational or non-investigational) product, whether or not related to that medicinal (investigational or non-investigational) product. Solicited local AEs were precisely defined local events that participants were specifically asked about and which were noted by participants in the diary. Solicited local AEs included injection-site pain/tenderness, injection-site erythema and injection-site swelling/induration.

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

100 participants

Primary outcome timeframe

14 days after first vaccination (Day 1 to Day 15)

Results posted on

2019-11-26

Participant Flow

Participant milestones

Participant milestones
Measure	ExPEC4V Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
Overall Study STARTED	75	25
Overall Study COMPLETED	66	22
Overall Study NOT COMPLETED	9	3

Reasons for withdrawal

Reasons for withdrawal
Measure	ExPEC4V Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
Overall Study Lost to Follow-up	6	3
Overall Study Withdrawal by Subject	3	0

Baseline Characteristics

A Study to Evaluate Safety and Immunogenicity of the ExPEC4V Clinical Trial Material After a Single Intramuscular Dose and a Second Dose 6 Months Later in Healthy Participants Aged 18 Years and Older

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	ExPEC4V n=75 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=25 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.	Total n=100 Participants Total of all reporting groups
Age, Continuous	55.7 years STANDARD_DEVIATION 18.86 • n=5 Participants	56.4 years STANDARD_DEVIATION 17.56 • n=7 Participants	55.9 years STANDARD_DEVIATION 18.45 • n=5 Participants
Sex: Female, Male Female	39 Participants n=5 Participants	13 Participants n=7 Participants	52 Participants n=5 Participants
Sex: Female, Male Male	36 Participants n=5 Participants	12 Participants n=7 Participants	48 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	5 Participants n=5 Participants	1 Participants n=7 Participants	6 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	69 Participants n=5 Participants	23 Participants n=7 Participants	92 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	1 Participants n=5 Participants	1 Participants n=7 Participants	2 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	1 Participants n=5 Participants	0 Participants n=7 Participants	1 Participants n=5 Participants
Race (NIH/OMB) Asian	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	1 Participants n=5 Participants	1 Participants n=7 Participants	2 Participants n=5 Participants
Race (NIH/OMB) Black or African American	6 Participants n=5 Participants	2 Participants n=7 Participants	8 Participants n=5 Participants
Race (NIH/OMB) White	63 Participants n=5 Participants	22 Participants n=7 Participants	85 Participants n=5 Participants
Race (NIH/OMB) More than one race	1 Participants n=5 Participants	0 Participants n=7 Participants	1 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	3 Participants n=5 Participants	0 Participants n=7 Participants	3 Participants n=5 Participants
Race/Ethnicity, Customized Black or African American	6 Participants n=5 Participants	2 Participants n=7 Participants	8 Participants n=5 Participants
Race/Ethnicity, Customized Hispanic or Latino	1 Participants n=5 Participants	0 Participants n=7 Participants	1 Participants n=5 Participants
Race/Ethnicity, Customized Other	7 Participants n=5 Participants	2 Participants n=7 Participants	9 Participants n=5 Participants
Race/Ethnicity, Customized White Non-Hispanic	61 Participants n=5 Participants	21 Participants n=7 Participants	82 Participants n=5 Participants
Region of Enrollment UNITED STATES	75 Participants n=5 Participants	25 Participants n=7 Participants	100 Participants n=5 Participants

PRIMARY outcome

Timeframe: 14 days after first vaccination (Day 1 to Day 15)

Population: The full analysis set (FAS) included all randomized participants with at least one study vaccine administration documented regardless of the occurrence of protocol deviations.

An AE is any untoward medical occurrence in a clinical study participant administered a medicinal (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the study vaccine. An AE can therefore be any unfavorable and unintended sign (including an abnormal finding), symptom, or disease temporally associated with the use of a medicinal (investigational or non-investigational) product, whether or not related to that medicinal (investigational or non-investigational) product. Solicited local AEs were precisely defined local events that participants were specifically asked about and which were noted by participants in the diary. Solicited local AEs included injection-site pain/tenderness, injection-site erythema and injection-site swelling/induration.

Outcome measures

Outcome measures
Measure	ExPEC4V n=75 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=25 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
Percentage of Participants With Solicited Local Adverse Events (AEs) After First Vaccination	38.7 Percentage of participants Interval 27.64 to 50.62	20.0 Percentage of participants Interval 6.83 to 40.7

PRIMARY outcome

Timeframe: 14 days after first vaccination (Day 1 to Day 15)

Population: The FAS included all randomized participants with at least one study vaccine administration documented regardless of the occurrence of protocol deviations.

An AE is any untoward medical occurrence in a clinical study participant administered a medicinal (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the study vaccine. An AE can therefore be any unfavorable and unintended sign (including an abnormal finding), symptom, or disease temporally associated with the use of a medicinal (investigational or non-investigational) product, whether or not related to that medicinal (investigational or non-investigational) product. Solicited systemic AEs were precisely defined systemic events that participants were specifically asked about and which were noted by participants in the diary. Solicited systemic AEs included fatigue, headache, nausea, myalgia and fever.

Outcome measures

Outcome measures
Measure	ExPEC4V n=75 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=25 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
Percentage of Participants With Solicited Systemic Adverse Events After First Vaccination	49.3 Percentage of participants Interval 37.58 to 61.14	20.0 Percentage of participants Interval 6.83 to 40.7

PRIMARY outcome

Timeframe: 29 days after first vaccination (Day 1 to Day 30)

Population: The FAS included all randomized participants with at least one study vaccine administration documented regardless of the occurrence of protocol deviations.

An AE is any untoward medical occurrence in a clinical study participant administered a medicinal (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the study vaccine. An AE can therefore be any unfavorable and unintended sign (including an abnormal finding), symptom, or disease temporally associated with the use of a medicinal (investigational or non-investigational) product, whether or not related to that medicinal (investigational or non-investigational) product. Unsolicited AEs were precisely defined events that participants were not asked about and which were not noted by participants in the diary.

Outcome measures

Outcome measures
Measure	ExPEC4V n=75 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=25 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
Percentage of Participants With Unsolicited Adverse Events After First Vaccination	30.7 Percentage of participants Interval 20.53 to 42.38	32.0 Percentage of participants Interval 14.95 to 53.5

PRIMARY outcome

Timeframe: Up to Day 180

Population: The FAS included all randomized participants with at least one study vaccine administration documented regardless of the occurrence of protocol deviations.

An AE is any untoward medical occurrence in a clinical study participant administered a medicinal (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the study vaccine. An AE can therefore be any unfavorable and unintended sign (including an abnormal finding), symptom, or disease temporally associated with the use of a medicinal (investigational or non-investigational) product, whether or not related to that medicinal (investigational or non-investigational) product. An SAE is any AE that results in: death, is life-threatening, requires inpatient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect and is a suspected transmission of any infectious agent via a medicinal product.

Outcome measures

Outcome measures
Measure	ExPEC4V n=75 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=25 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
Number of Participants With Serious Adverse Events (SAEs) After First Vaccination	1 Participants	1 Participants

PRIMARY outcome

Timeframe: Day 1

Population: The per-protocol immunogenicity (PPI) analysis set consisted of all participants from the FAS excluding those with major protocol deviations expecting to impact the immunogenicity outcomes.

Immunoglobulin G (IgG) antibody levels elicited by the vaccine against each of the 4 vaccine serotypes (serotype O1A, O2, O6A and O25B) were measured by ELISA. GMTs for serotypes O1A, O2, O6A and O25B at Day 1 were reported.

Outcome measures

Outcome measures
Measure	ExPEC4V n=74 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=24 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
Enzyme-linked Immunosorbent Assay (ELISA) Geometric Mean Titers (GMTs) for Serotypes O1A, O2, O6A and O25B at Day 1 Serotype O1A	3177.8 Titer Interval 2412.54 to 4185.68	3113.7 Titer Interval 1910.56 to 5074.63
Enzyme-linked Immunosorbent Assay (ELISA) Geometric Mean Titers (GMTs) for Serotypes O1A, O2, O6A and O25B at Day 1 Serotype O2	3598.1 Titer Interval 2865.83 to 4517.54	4127.3 Titer Interval 2182.46 to 7805.05
Enzyme-linked Immunosorbent Assay (ELISA) Geometric Mean Titers (GMTs) for Serotypes O1A, O2, O6A and O25B at Day 1 Serotype O6A	864.6 Titer Interval 664.08 to 1125.58	817.9 Titer Interval 473.94 to 1411.46
Enzyme-linked Immunosorbent Assay (ELISA) Geometric Mean Titers (GMTs) for Serotypes O1A, O2, O6A and O25B at Day 1 Serotype O25B	375.3 Titer Interval 285.25 to 493.69	550.8 Titer Interval 288.87 to 1050.27

PRIMARY outcome

Timeframe: Day 15

Population: The PPI analysis set consisted of all participants from the FAS excluding those with major protocol deviations expecting to impact the immunogenicity outcomes. Here 'N' (number of participants analyzed) signifies number of participants evaluable for this outcome measure.

IgG antibody levels elicited by the vaccine against each of the 4 vaccine serotypes (serotype O1A, O2, O6A and O25B) were measured by ELISA. GMTs for serotypes O1A, O2, O6A and O25B at Day 15 were reported.

Outcome measures

Outcome measures
Measure	ExPEC4V n=73 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=24 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
ELISA GMTs for Serotypes O1A, O2, O6A and O25B at Day 15 Serotype O1A	17030.3 Titer Interval 13048.22 to 22227.66	2838.2 Titer Interval 1749.61 to 4604.01
ELISA GMTs for Serotypes O1A, O2, O6A and O25B at Day 15 Serotype O2	44704.8 Titer Interval 33459.35 to 59729.66	3761.6 Titer Interval 2129.94 to 6643.37
ELISA GMTs for Serotypes O1A, O2, O6A and O25B at Day 15 Serotype O6A	8206.6 Titer Interval 6241.05 to 10791.06	746.2 Titer Interval 444.1 to 1253.75
ELISA GMTs for Serotypes O1A, O2, O6A and O25B at Day 15 Serotype O25B	6132.4 Titer Interval 4280.78 to 8784.88	467.1 Titer Interval 249.47 to 874.61

PRIMARY outcome

Timeframe: Day 15/Day 1

Population: The PPI analysis set consisted of all participants from the FAS excluding those with major protocol deviations expecting to impact the immunogenicity outcomes. Here 'N' (number of participants analyzed) signifies number of participants evaluable for this outcome measure.

IgG antibody levels elicited by the vaccine against each of the 4 vaccine serotypes (serotype O1A, O2, O6A and O25B) were measured by ELISA. GMR for serotypes O1A, O2, O6A and O25B (Day 15/Day 1) was reported.

Outcome measures

Outcome measures
Measure	ExPEC4V n=73 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=24 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
ELISA Geometric Mean Ratio (GMR) for Serotypes O1A, O2, O6A and O25B at Day 15/Day 1 Serotype O1A	5.22 Ratio Interval 4.142 to 6.568	0.91 Ratio Interval 0.799 to 1.04
ELISA Geometric Mean Ratio (GMR) for Serotypes O1A, O2, O6A and O25B at Day 15/Day 1 Serotype O2	12.06 Ratio Interval 9.221 to 15.771	0.89 Ratio Interval 0.682 to 1.149
ELISA Geometric Mean Ratio (GMR) for Serotypes O1A, O2, O6A and O25B at Day 15/Day 1 Serotype O6A	8.61 Ratio Interval 6.515 to 11.379	0.94 Ratio Interval 0.817 to 1.079
ELISA Geometric Mean Ratio (GMR) for Serotypes O1A, O2, O6A and O25B at Day 15/Day 1 Serotype O25B	12.02 Ratio Interval 8.46 to 17.09	0.87 Ratio Interval 0.658 to 1.159

PRIMARY outcome

Timeframe: Day 15

Population: The PPI analysis set consisted of all participants from the FAS excluding those with major protocol deviations expecting to impact the immunogenicity outcomes. Here 'N' (number of participants analyzed) signifies number of participants evaluable for this outcome measure.

Percentage of participants with a 2-fold and 4-fold increase from baseline in serum antibody titers as measured by ELISA at Day 15 were reported.

Outcome measures

Outcome measures
Measure	ExPEC4V n=73 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=24 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
Percentage of Participants With a 2-fold and 4-fold Increase From Baseline in Serum Antibody Titers (ELISA) at Day 15 Serotype O1A: ELISA 2-fold	82.2 Percentage of participants Interval 71.47 to 90.16	0.0 Percentage of participants Interval 0.0 to 14.25
Percentage of Participants With a 2-fold and 4-fold Increase From Baseline in Serum Antibody Titers (ELISA) at Day 15 Serotype O1A: ELISA 4-fold	57.5 Percentage of participants Interval 45.41 to 69.03	0.0 Percentage of participants Interval 0.0 to 14.25
Percentage of Participants With a 2-fold and 4-fold Increase From Baseline in Serum Antibody Titers (ELISA) at Day 15 Serotype O2: ELISA 2-fold	91.8 Percentage of participants Interval 82.96 to 96.92	0.0 Percentage of participants Interval 0.0 to 14.25
Percentage of Participants With a 2-fold and 4-fold Increase From Baseline in Serum Antibody Titers (ELISA) at Day 15 Serotype O2: ELISA 4-fold	83.6 Percentage of participants Interval 73.05 to 91.21	0.0 Percentage of participants Interval 0.0 to 14.25
Percentage of Participants With a 2-fold and 4-fold Increase From Baseline in Serum Antibody Titers (ELISA) at Day 15 Serotype O6A: ELISA 2-fold	84.9 Percentage of participants Interval 74.64 to 92.23	0.0 Percentage of participants Interval 0.0 to 14.25
Percentage of Participants With a 2-fold and 4-fold Increase From Baseline in Serum Antibody Titers (ELISA) at Day 15 Serotype O6A: ELISA 4-fold	75.3 Percentage of participants Interval 63.86 to 84.68	0.0 Percentage of participants Interval 0.0 to 14.25
Percentage of Participants With a 2-fold and 4-fold Increase From Baseline in Serum Antibody Titers (ELISA) at Day 15 Serotype O25B: ELISA 2-fold	89.0 Percentage of participants Interval 79.54 to 95.15	0.0 Percentage of participants Interval 0.0 to 14.25
Percentage of Participants With a 2-fold and 4-fold Increase From Baseline in Serum Antibody Titers (ELISA) at Day 15 Serotype O25B: ELISA 4-fold	75.3 Percentage of participants Interval 63.86 to 84.68	0.0 Percentage of participants Interval 0.0 to 14.25

SECONDARY outcome

Timeframe: 14 days after second vaccination (Day 181 to Day 195)

Population: The FAS included all randomized participants with at least one study vaccine administration documented regardless of the occurrence of protocol deviations. Here 'N' (number of participants analyzed) signifies number of participants evaluable for this outcome measure.

An AE is any untoward medical occurrence in a clinical study participant administered a medicinal (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the study vaccine. An AE can therefore be any unfavorable and unintended sign (including an abnormal finding), symptom, or disease temporally associated with the use of a medicinal (investigational or non-investigational) product, whether or not related to that medicinal (investigational or non-investigational) product. Solicited local AEs were precisely defined local events that participants were specifically asked about and which were noted by participants in the diary. Solicited local AEs included injection-site pain/tenderness, injection-site erythema and injection-site swelling/induration.

Outcome measures

Outcome measures
Measure	ExPEC4V n=68 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=24 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
Percentage of Participants With Solicited Local Adverse Events After Second Vaccination	45.6 Percentage of participants Interval 33.45 to 58.12	4.2 Percentage of participants Interval 0.11 to 21.12

SECONDARY outcome

Timeframe: 14 days after second vaccination (Day 181 to Day 195)

Population: The FAS included all randomized participants with at least one study vaccine administration documented regardless of the occurrence of protocol deviations. Here 'N' (number of participants analyzed) signifies number of participants evaluable for this outcome measure.

An AE is any untoward medical occurrence in a clinical study participant administered a medicinal (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the study vaccine. An AE can therefore be any unfavorable and unintended sign (including an abnormal finding), symptom, or disease temporally associated with the use of a medicinal (investigational or non-investigational) product, whether or not related to that medicinal (investigational or non-investigational) product. Solicited systemic AEs were precisely defined systemic events that participants were specifically asked about and which were noted by participants in the diary. Solicited systemic AEs included fatigue, headache, nausea, myalgia and fever.

Outcome measures

Outcome measures
Measure	ExPEC4V n=68 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=24 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
Percentage of Participants With Solicited Systemic Adverse Events After Second Vaccination	48.5 Percentage of participants Interval 36.22 to 60.97	29.2 Percentage of participants Interval 12.62 to 51.09

SECONDARY outcome

Timeframe: 29 days after second vaccination (Day 181 to Day 210)

Population: The FAS included all randomized participants with at least one study vaccine administration documented regardless of the occurrence of protocol deviations. Here 'N' (number of participants analyzed) signifies number of participants evaluable for this outcome measure.

An AE is any untoward medical occurrence in a clinical study participant administered a medicinal (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the study vaccine. An AE can therefore be any unfavorable and unintended sign (including an abnormal finding), symptom, or disease temporally associated with the use of a medicinal (investigational or non-investigational) product, whether or not related to that medicinal (investigational or non-investigational) product. Unsolicited AEs were precisely defined events that participants were not asked about and which were not noted by participants in the diary.

Outcome measures

Outcome measures
Measure	ExPEC4V n=68 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=24 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
Percentage of Participants With Unsolicited Adverse Events After Second Vaccination	11.8 Percentage of participants Interval 5.22 to 21.87	8.3 Percentage of participants Interval 1.03 to 27.0

SECONDARY outcome

Timeframe: Day 181 until Day 360

Population: The FAS included all randomized participants with at least one study vaccine administration documented regardless of the occurrence of protocol deviations. Here 'N' (number of participants analyzed) signifies number of participants evaluable for this outcome measure.

An AE is any untoward medical occurrence in a clinical study participant administered a medicinal (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the study vaccine. An AE can therefore be any unfavorable and unintended sign (including an abnormal finding), symptom, or disease temporally associated with the use of a medicinal (investigational or non-investigational) product, whether or not related to that medicinal (investigational or non-investigational) product. An SAE is any AE that results in: death, is life-threatening, requires inpatient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect and is a suspected transmission of any infectious agent via a medicinal product.

Outcome measures

Outcome measures
Measure	ExPEC4V n=68 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=24 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
Number of Participants With Serious Adverse Events After Second Vaccination	1 Participants	0 Participants

SECONDARY outcome

Timeframe: Days 1 and 15

Population: The PPI analysis set consisted of all participants from the FAS excluding those with major protocol deviations expecting to impact the immunogenicity outcomes. Here 'n' (number analyzed) signifies number of participants evaluable for specified time points for specified categories.

Specific functional antibacterial antibodies were measured by OPKA. GMTs for serotypes O1A, O2, O6A and O25B at Days 1 and 15 were reported.

Outcome measures

Outcome measures
Measure	ExPEC4V n=74 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=24 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
Opsonophagocytic Killing Assay (OPKA) GMTs for Serotypes O1A, O2, O6A and O25B at Days 1 and 15 Serotype O1A: Day 1	156.8 Titer Interval 131.76 to 186.53	173.0 Titer Interval 116.55 to 256.69
Opsonophagocytic Killing Assay (OPKA) GMTs for Serotypes O1A, O2, O6A and O25B at Days 1 and 15 Serotype O1A: Day 15	735.6 Titer Interval 535.33 to 1010.75	165.3 Titer Interval 111.87 to 244.12
Opsonophagocytic Killing Assay (OPKA) GMTs for Serotypes O1A, O2, O6A and O25B at Days 1 and 15 Serotype O2: Day 1	207.2 Titer Interval 167.79 to 255.74	295.0 Titer Interval 179.18 to 485.64
Opsonophagocytic Killing Assay (OPKA) GMTs for Serotypes O1A, O2, O6A and O25B at Days 1 and 15 Serotype O2: Day 15	2667.3 Titer Interval 1896.34 to 3751.64	241.8 Titer Interval 156.39 to 373.8
Opsonophagocytic Killing Assay (OPKA) GMTs for Serotypes O1A, O2, O6A and O25B at Days 1 and 15 Serotype O6A: Day 1	304.8 Titer Interval 229.09 to 405.46	380.7 Titer Interval 217.04 to 667.59
Opsonophagocytic Killing Assay (OPKA) GMTs for Serotypes O1A, O2, O6A and O25B at Days 1 and 15 Serotype O6A: Day 15	802.4 Titer Interval 632.29 to 1018.16	468.5 Titer Interval 241.48 to 908.8
Opsonophagocytic Killing Assay (OPKA) GMTs for Serotypes O1A, O2, O6A and O25B at Days 1 and 15 Serotype O25B: Day 1	68.8 Titer Interval 54.64 to 86.65	59.3 Titer Interval 39.08 to 90.08
Opsonophagocytic Killing Assay (OPKA) GMTs for Serotypes O1A, O2, O6A and O25B at Days 1 and 15 Serotype O25B: Day 15	188.9 Titer Interval 141.11 to 252.78	51.9 Titer Interval 35.59 to 75.63

SECONDARY outcome

Timeframe: Day 15/Day 1

Population: The PPI analysis set consisted of all participants from the FAS excluding those with major protocol deviations expecting to impact the immunogenicity outcomes. Here 'N' (number of participants analyzed) signifies number of participants evaluable for this outcome measure.

Specific functional antibacterial antibodies were measured by OPKA. GMR for serotypes O1A, O2, O6A and O25B (Day 15/Day 1) was reported.

Outcome measures

Outcome measures
Measure	ExPEC4V n=73 Participants Participants received a single 0.5 milliliter (mL) dose of ExPEC4V vaccine as an intramuscular (IM) injection into the deltoid muscle on Day 1 and Day 181.	Placebo n=24 Participants Participants received placebo matching to ExPEC4V as an IM injection into the deltoid muscle on Day 1 and Day 181.
OPKA GMR for Serotypes O1A, O2, O6A and O25B at Day 15/Day 1 Serotype O1A	3.47 Ratio Interval 2.687 to 4.479	0.98 Ratio Interval 0.959 to 1.009
OPKA GMR for Serotypes O1A, O2, O6A and O25B at Day 15/Day 1 Serotype O2	10.78 Ratio Interval 7.943 to 14.631	0.84 Ratio Interval 0.629 to 1.132
OPKA GMR for Serotypes O1A, O2, O6A and O25B at Day 15/Day 1 Serotype O6A	2.49 Ratio Interval 1.989 to 3.12	1.23 Ratio Interval 0.834 to 1.816
OPKA GMR for Serotypes O1A, O2, O6A and O25B at Day 15/Day 1 Serotype O25B	2.37 Ratio Interval 1.892 to 2.976	0.87 Ratio Interval 0.739 to 1.034

SECONDARY outcome

Timeframe: Day 15

Population: The PPI analysis set consisted of all participants from the FAS excluding those with major protocol deviations expecting to impact the immunogenicity outcomes. Here 'N' (number of participants analyzed) signifies number of participants evaluable for this outcome measure.

Percentage of participants with a 2-fold and 4-fold increase from baseline in serum antibody titers as measured by OPKA at Day 15 were reported.