Seroconversion was defined as a 4-fold increase in Nab titers as compared to the pre-vaccination value. YF-naive participants (or negative) at baseline corresponded to participants with no detectable YF antibody (Ab) titers before vaccination. The YF NAb titers were determined using a validated live virus microneutralization (MN) assay. Percentages are rounded off to the tenth decimal place.

The per-protocol analysis set (PPAS) was a subset of the full analysis set (FAS). The FAS included the subset of randomized participants who received at least 1 dose of the study vaccine or control vaccine and had a valid post-vaccination blood sample result.

Seroconversion was defined as a 4-fold increase in Nab titers as compared to the pre-vaccination value: compared to the Day 1 titers at each timepoint up to Month 6; and to the last planned previous timepoint from Year 1 onwards. The YF NAb titers were determined using a validated live virus MN assay. Percentages are rounded off to the tenth decimal place.

The FAS included subset of randomized participants who received at least 1 dose of study vaccine or control vaccine and had a valid post-vaccination blood sample result. Day 11: a subset of participants enrolled at some sites provided an additional post-vaccination blood sample on Day 11 to assess the immune response elicited by both vaccines in terms of NAb titers. Only participants with data collected at specified timepoints are reported.

Seroprotection was defined as NAb titers >=threshold of 10 (1/dilution). The YF NAb titers were determined using a validated live virus MN assay. Percentages are rounded off to the tenth decimal place.

The FAS included subset of randomized participants who received at least 1 dose of study vaccine or control vaccine and had a valid post-vaccination blood sample result. Day 11: a subset of participants enrolled at some sites provided an additional post-vaccination blood sample on Day 11 to assess the immune response elicited by both vaccines in terms of NAb titers. Only participants with data collected at specified timepoints are reported.

GMTs of antibody against YF virus was measured using a validated live virus MN assay.

The FAS included subset of randomized participants who received at least 1 dose of study vaccine or control vaccine and had a valid post-vaccination blood sample result. Day 11: a subset of participants enrolled at some sites provided an additional post-vaccination blood sample on Day 11 to assess the immune response elicited by both vaccines in terms of NAb titers. Only participants with data collected at specified timepoints are reported.

GMTs of antibody against YF virus was measured using a validated live virus MN assay. Ratio was calculated as post-vaccination titer at Days 11, 29 and Month 6 to pre-vaccination titer at Day 1; post-vaccination titer at Year 1 to pre-vaccination titer at Month 6; post-vaccination titer at Year 2 to pre-vaccination titer at Year 1.

The FAS included subset of randomized participants who received at least 1 dose of study vaccine or control vaccine and had a valid post-vaccination blood sample result. Day 11: a subset of participants enrolled at some sites provided an additional post-vaccination blood sample on Day 11 to assess the immune response elicited by both vaccines in terms of NAb titers. Only participants with data collected at specified timepoints are reported.

An unsolicited AE was an observed AE that did not fulfill the conditions of solicited reactions, ie, pre-listed in the CRF in terms of diagnosis and onset window post-vaccination.

The safety analysis set (SafAS) included all participants who received at least 1 dose of the study vaccines.

A solicited reaction was an "expected" adverse reaction (AR) (sign or symptom) observed and reported under the conditions (nature and onset) pre-listed in the protocol and CRF. An injection site reaction was an AR at and around the injection site of the study vaccine.

The SafAS included all participants who received at least 1 dose of the study vaccines. Only participants with data collected are reported.

A solicited reaction was an "expected" AR (sign or symptom) observed and reported under the conditions (nature and onset) pre-listed in the protocol and CRF. Solicited systemic reactions were systemic AEs observed and reported under the conditions (nature and onset) pre-listed in the protocol and CRF.

The SafAS included all participants who received at least 1 dose of the study vaccines. Only participants with data collected are reported.

An unsolicited AE was an observed AE that did not fulfill the conditions of solicited reactions, ie, pre-listed in the CRF in terms of diagnosis and onset window post-vaccination.

The SafAS included all participants who received at least 1 dose of the study vaccines.

An SAE was any AE 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 (serious or non-serious) was defined as one of scientific and medical concern specific to the Sponsor's study intervention or program, for which ongoing monitoring and rapid communication by the Investigator to the Sponsor could be appropriate. AESIs included serious hypersensitivity/allergic reactions, organ failure/serious viscerotropic events, serious neurologic events.

The SafAS included all participants who received at least 1 dose of the study vaccines.

An SAE was any AE 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.

The SafAS included all participants who received at least 1 dose of the study vaccines.

An SAE was any AE 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.

Blood samples were collected at specified timepoints for assessment of biochemistry parameters: alanine aminotransferase (ALT), aspartate transaminase (AST), creatine phosphokinase (CPK), alkaline phosphatase (ALP), bilirubin (accompanied by any increase in liver function test (LFT) and normal LFT), creatinine and C-reactive protein (CRP). The intensity grading scale for laboratory abnormalities was pre-specified in the protocol. Number of participants with out-of-range biochemistry parameters are presented.

Analysis was performed on a subset of participants enrolled at some sites who provided an additional post-vaccination blood sample to assess the biological safety parameters on Days 1 and 11. Only participants with data collected on Days 1 and 11 are reported.

Blood samples were collected at specified timepoints for assessment of hematology parameters: red blood cell count (RBC), hematocrit, mean corpuscular volume (MCV), monocytes, basophils, hemoglobin (Hb), white blood cell count (WBC) (increase and decrease), neutrophils and lymphocytes (decrease), eosinophils, platelets (decrease). The intensity grading scale for laboratory abnormalities was pre-specified in the protocol. Number of participants with out-of-range hematology parameters are presented.

Analysis was performed on a subset of participants enrolled at some sites who provided an additional post-vaccination blood sample to assess the biological safety parameters on Days 1 and 11. Only participants with data collected on Days 1 and 11 are reported.