Normal saline placebo.

An AE is defined as any untoward medical occurrence in a participant which does not necessarily have a causal relationship with study vaccine. A TEAE is defined as an AE that starts or worsens on or after the date and time of the study vaccination. Systemic reactogenicity signs and symptoms include pyrexia (subjective and objective fever), chills, hyperhidrosis (sweats), myalgia, arthralgia, fatigue, headache, and gastrointestinal symptoms including nausea, vomiting, abdominal pain, and/or diarrhea. AEs were assessed for severity by the investigator as follows: Grade 1=Mild; Grade 2=Moderate; Grade 3=Severe; Grade 4=Potentially life-threatening. The number of participants that experienced at least 1 solicited systemic TEAE was summarized by grade. Solicited TEAEs occurred from the time of each injection through 14 days following the procedure, facilitated with the use of a memory aid to record participant observations.

An adverse event (AE) is defined as any untoward medical occurrence in a participant which does not necessarily have a causal relationship with study vaccine. A treatment-emergent adverse event is defined as an AE that starts or worsens on or after the date and time of the study vaccination. The number of participants that experienced at least one unsolicited TEAE was assessed. Unsolicited AEs occurred from the time of injection through 28 days following injection.

An adverse event (AE) is defined as any untoward medical occurrence in a participant which does not necessarily have a causal relationship with study vaccine. A treatment-emergent adverse event is defined as an AE that starts or worsens on or after the date and time of the study vaccination. A related TEAE is defined as a TEAE that was possibly, probably, or definitely related to the vaccination as assessed by the investigator. The number of participants that experienced at least one unsolicited TEAE related to study vaccination was assessed.

An adverse event (AE) is defined as any untoward medical occurrence in a participant which does not necessarily have a causal relationship with study vaccine. A treatment-emergent adverse event is defined as an AE that starts or worsens on or after the date and time of the study vaccination. A related TEAE is defined as a TEAE that was possibly, probably, or definitely related to the vaccination as assessed by the investigator. AEs were assessed for severity by the investigator according to a toxicity grading scale based on the FDA's Guidance for Industry "Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials": Grade 1=Mild; Grade 2=Moderate; Grade 3=Severe; Grade 4=Potentially life-threatening. The number of participants that experienced at least one unsolicited TEAE related to study vaccination was summarized by grade.

An adverse event (AE) is defined as any untoward medical occurrence in a participant which does not necessarily have a causal relationship with study vaccine. The number of participants prematurely withdrawing from the study due to an AE was assessed.

An adverse event is defined as any untoward medical occurrence in a participant which does not necessarily have a causal relationship with study vaccine. A serious adverse event (SAE) is an AE that results in death, is life-threatening, results in a persistent or significant disability or incapacity, results in or prolongs an existing hospitalization, is a congenital anomaly or birth defect, or is another important medical event. The number of participants that experienced one or more SAE was summarized.

The Geometric Mean Titers (GMT) of ZEBOV-specific neutralizing antibodies were measured by pseudovirion neutralization assays (PsVNA). Titers were reported for PsVNA50 values which were derived from the reciprocal of the dilution that resulted in a 50% decrease in luciferase activity. The LLOQ for the PsVNA was 20. If the PsVNA was reported ≤20, the numeric portion of the titer was divided by 2 for statistical purposes, which could result in a reported GMT <20.0. PsVNA50 titers at baseline (Day 0) and analysis Days 7, 14, 28, 56, and 180 were summarized by V920 vaccine dose level and placebo as the mean of log10 titers, transformed into GMT. The geometric standard deviation (GSD) for the GMT at each visit was obtained by exponentiating the standard deviation for the mean of log (base 10) transformed titers.

The number of participants with viremia detected by recombinant vesicular stomatitis virus (rVSV) reverse transcription polymerase chain reaction (PCR) of blood specimens was assessed.

The number of participants with viremia detected by rVSV reverse transcription PCR of saliva or urine specimens was assessed.

Although the protocol specified a secondary endpoint that included the mean copy number of vector RNA (vector viremia), the Polymerase Chain Reaction (PCR) test used for the study reported a qualitative rather than a quantitative outcome, so the proportion of participants with viremia is reported instead of the mean copy number of vector RNA. Qualitative results are therefore reported in Outcome Measures 12 and 13.

Participants will receive a 1-mL intramuscular injection of V920 1x10^8 pfu in one deltoid and a 1-mL intramuscular injection of placebo in the contralateral deltoid on Day 0.

Participants will receive a 1-mL intramuscular injection of placebo in each deltoid on Day 0.

Total of all reporting groups

Participants will receive a 1-mL intramuscular injection of V920 2x10^7 pfu in one deltoid and a 1-mL intramuscular injection of placebo in the contralateral deltoid on Day 0.

Participants will receive a 1-mL intramuscular injection of V920 1x10^8 pfu in one deltoid and a 1-mL intramuscular injection of placebo in the contralateral deltoid on Day 0.

Participants will receive a 1-mL intramuscular injection of placebo in each deltoid on Day 0.

An AE is defined as any untoward medical occurrence in a participant which does not necessarily have a causal relationship with study vaccine. A TEAE is defined as an AE that starts or worsens on or after the date and time of the study vaccination. Local reactogenicity signs and symptoms include pain, erythema (redness), and induration (swelling). AEs were assessed for severity by the investigator according to a toxicity grading scale based on the FDA's Guidance for Industry "Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials": Grade 1=Mild; Grade 2=Moderate; Grade 3=Severe; Grade 4=Potentially life-threatening. The number of participants that experienced at least one solicited local TEAE was summarized by grade. Solicited TEAEs occurred from the time of each injection through 14 days following the procedure, facilitated with the use of a memory aid to record participant observations.

All randomized participants who received study vaccination (V920 dose level or placebo).

An adverse event (AE) is defined as any untoward medical occurrence in a participant which does not necessarily have a causal relationship with study vaccine. A treatment-emergent adverse event is defined as an AE that starts or worsens on or after the date and time of the study vaccination. Systemic reactogenicity signs and symptoms include pyrexia (subjective and objective fever), chills, hyperhidrosis (sweats), myalgia, arthralgia, fatigue, headache, and gastrointestinal symptoms including nausea, vomiting, abdominal pain, and/or diarrhea. The number of participants that experienced at least one solicited systemic TEAE was assessed. Solicited TEAEs occurred from the time of each injection through 14 days following the procedure, facilitated with the use of a memory aid to record participant observations.

All randomized participants who received study vaccination (V920 dose level or placebo).

An AE is defined as any untoward medical occurrence in a participant which does not necessarily have a causal relationship with study vaccine. A TEAE is defined as an AE that starts or worsens on or after the date and time of the study vaccination. Systemic reactogenicity signs and symptoms include pyrexia (subjective and objective fever), chills, hyperhidrosis (sweats), myalgia, arthralgia, fatigue, headache, and gastrointestinal symptoms including nausea, vomiting, abdominal pain, and/or diarrhea. AEs were assessed for severity by the investigator as follows: Grade 1=Mild; Grade 2=Moderate; Grade 3=Severe; Grade 4=Potentially life-threatening. The number of participants that experienced at least 1 solicited systemic TEAE was summarized by grade. Solicited TEAEs occurred from the time of each injection through 14 days following the procedure, facilitated with the use of a memory aid to record participant observations.

All randomized participants who received study vaccination (V920 dose level or placebo).

An adverse event (AE) is defined as any untoward medical occurrence in a participant which does not necessarily have a causal relationship with study vaccine. A treatment-emergent adverse event is defined as an AE that starts or worsens on or after the date and time of the study vaccination. The number of participants that experienced at least one unsolicited TEAE was assessed. Unsolicited AEs occurred from the time of injection through 28 days following injection.

All randomized participants who received study vaccination (V920 dose level or placebo).

An adverse event (AE) is defined as any untoward medical occurrence in a participant which does not necessarily have a causal relationship with study vaccine. A treatment-emergent adverse event is defined as an AE that starts or worsens on or after the date and time of the study vaccination. A related TEAE is defined as a TEAE that was possibly, probably, or definitely related to the vaccination as assessed by the investigator. The number of participants that experienced at least one unsolicited TEAE related to study vaccination was assessed.

All randomized participants who received study vaccination (V920 dose or placebo).

An adverse event (AE) is defined as any untoward medical occurrence in a participant which does not necessarily have a causal relationship with study vaccine. A treatment-emergent adverse event is defined as an AE that starts or worsens on or after the date and time of the study vaccination. A related TEAE is defined as a TEAE that was possibly, probably, or definitely related to the vaccination as assessed by the investigator. AEs were assessed for severity by the investigator according to a toxicity grading scale based on the FDA's Guidance for Industry "Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials": Grade 1=Mild; Grade 2=Moderate; Grade 3=Severe; Grade 4=Potentially life-threatening. The number of participants that experienced at least one unsolicited TEAE related to study vaccination was summarized by grade.

All randomized participants who received study vaccination (V920 dose level or placebo).

An adverse event (AE) is defined as any untoward medical occurrence in a participant which does not necessarily have a causal relationship with study vaccine. The number of participants prematurely withdrawing from the study due to an AE was assessed.

All randomized participants who received study vaccination (V920 dose level or placebo).

The Geometric Mean Titers (GMT) of ZEBOV-specific Immunoglobulin G antibodies were measured by unqualified ZEBOV immunoglobulin (IgG) enzyme-linked immunosorbent assay (ELISA). For titers expressed in ELISA Units/mL, the lower level of quantitation (LLOQ) was 58.84. ZEBOV IgG titers at baseline (Day 0) and analysis Days 7, 14, 28, 56, 84, and 180 were summarized by V920 vaccine dose level and placebo as the mean of log10 titers, transformed into GMT. The geometric standard deviation (GSD) for the GMT at each visit was obtained by exponentiating the standard deviation for the mean of log (base 10) transformed titers.

All randomized participants who were vaccinated and had an evaluable Day 28 immunogenicity result following vaccination and who did not have any protocol deviations that influenced interpretation of immunogenicity endpoints for the specified measurement and timeframe.

The Geometric Mean Titers (GMT) of ZEBOV-specific neutralizing antibodies were measured by pseudovirion neutralization assays (PsVNA). Titers were reported for PsVNA50 values which were derived from the reciprocal of the dilution that resulted in a 50% decrease in luciferase activity. The LLOQ for the PsVNA was 20. If the PsVNA was reported ≤20, the numeric portion of the titer was divided by 2 for statistical purposes, which could result in a reported GMT <20.0. PsVNA50 titers at baseline (Day 0) and analysis Days 7, 14, 28, 56, and 180 were summarized by V920 vaccine dose level and placebo as the mean of log10 titers, transformed into GMT. The geometric standard deviation (GSD) for the GMT at each visit was obtained by exponentiating the standard deviation for the mean of log (base 10) transformed titers.

All randomized participants who were vaccinated and had an evaluable Day 28 immunogenicity result following vaccination and who did not have any protocol deviations that influenced interpretation of immunogenicity endpoints for the specified measurement and timeframe.

The number of participants with viremia detected by recombinant vesicular stomatitis virus (rVSV) reverse transcription polymerase chain reaction (PCR) of blood specimens was assessed.

All randomized subjects who were vaccinated and had an evaluable Day 28 immunogenicity result following vaccination and who did not have any protocol deviations that influenced interpretation of immunogenicity endpoints.

The number of participants with viremia detected by rVSV reverse transcription PCR of saliva or urine specimens was assessed.

All randomized subjects who were vaccinated and had an evaluable Day 28 immunogenicity result following vaccination and who did not have any protocol deviations that influenced interpretation of immunogenicity endpoints.

An adverse event is defined as any untoward medical occurrence in a participant which does not necessarily have a causal relationship with study vaccine. A serious adverse event (SAE) is an AE that results in death, is life-threatening, results in a persistent or significant disability or incapacity, results in or prolongs an existing hospitalization, is a congenital anomaly or birth defect, or is another important medical event. The number of participants that experienced one or more SAE was summarized.

All participants who received study vaccination (V920 dose level or placebo).

Although the protocol specified a secondary endpoint that included the mean copy number of vector RNA (vector viremia), the Polymerase Chain Reaction (PCR) test used for the study reported a qualitative rather than a quantitative outcome, so the proportion of participants with viremia is reported instead of the mean copy number of vector RNA. Qualitative results are therefore reported in Outcome Measures 12 and 13.

Although the plan specified in the protocol was to describe vector viremia by summarizing simple mean copy numbers of vector RNA, this data was not collected as the PCR results were qualitative rather than quantitative and were assessed in outcome measures # 12 and #13 instead.

Participants will receive a 1-mL intramuscular injection of V920 2x10^7 pfu in one deltoid and a 1-mL intramuscular injection of placebo in the contralateral deltoid on Day 0.

Participants will receive a 1-mL intramuscular injection of V920 1x10^8 pfu in one deltoid and a 1-mL intramuscular injection of placebo in the contralateral deltoid on Day 0.

Participants will receive a 1-mL intramuscular injection of placebo in each deltoid on Day 0.

Day 28

Adjustments for multiple comparisons were not performed.

p-values are pairwise comparisons of log-transformed titers between each V920 dose, between each V920 dose and placebo, between all V920 dose levels combined and placebo and are from an ANOVA model.

Day 28

Adjustments for multiple comparisons were not performed.

p-values are pairwise comparisons of log-transformed titers between each V920 dose, between each V920 dose and placebo, between all V920 dose levels combined and placebo and are from an ANOVA model.

Day 28

Adjustments for multiple comparisons were not performed.

p-values are pairwise comparisons of log-transformed titers between each V920 dose, between each V920 dose and placebo, between all V920 dose levels combined and placebo and are from an ANOVA model.

Day 28

Adjustments for multiple comparisons were not performed.

p-values are pairwise comparisons of log-transformed titers between each V920 dose, between each V920 dose and placebo, between all V920 dose levels combined and placebo and are from an ANOVA model.

Day 28

Adjustments for multiple comparisons were not performed.

p-values are pairwise comparisons of log-transformed titers between each V920 dose, between each V920 dose and placebo, between all V920 dose levels combined and placebo and are from an ANOVA model.

Day 28

Adjustments for multiple comparisons were not performed.

p-values are pairwise comparisons of log-transformed titers between each V920 dose, between each V920 dose and placebo, between all V920 dose levels combined and placebo and are from an ANOVA model.

Day 28

Adjustments for multiple comparisons were not performed.

p-values are pairwise comparisons of log-transformed titers between each V920 dose, between each V920 dose and placebo, between all V920 dose levels combined and placebo and are from an ANOVA model.

Day 28

Adjustments for multiple comparisons were not performed.

p-values are pairwise comparisons of log-transformed titers between each V920 dose, between each V920 dose and placebo, between all V920 dose levels combined and placebo and are from an ANOVA model.