The varicella zoster virus (VZV) antibody response rate was defined as the percentage of participants with VZV antibody titer ≥5 glycoprotein enzyme-linked immunosorbent assay (gpELISA) units/mL among participants who were seronegative to VZV (titers <1.25 gpELISA units/mL) at baseline.

The analysis population included the number of participants with seronegative antibody titer (<1.25 gpELISA units/mL) at baseline and postvaccination serology.

The geometric mean titer (GMT) of VZV antibodies after vaccination 1 was assessed. Antibody titers were measured with gpELISA.

The analysis population included the number of participants with seronegative antibody titer (<1.25 gpELISA units/mL) at baseline and postvaccination serology.

The percentage of participants with fever ≥102.2 °F oral equivalent for Day 1 through Day 42 after vaccination 1 and Day 1 through Day 42 after vaccination 2 was reported.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with temperature data at the time of assessment.

The percentage of participants with measles-like, rubella-like, varicella-like, zoster-like rash, and mumps-like symptoms after vaccination 1 was assessed. A specific adverse event was reported only if its incidence was >0% in one or more vaccination groups after rounding.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with data at the time of assessment.

The percentage of participants with measles-like, rubella-like, varicella-like, zoster-like rash, and mumps-like symptoms after vaccination 2 was assessed. A specific adverse event was reported only if its incidence was >0% in one or more vaccination groups after rounding.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with data at the time of assessment.

The percentage of participants with solicited (on a Vaccine Report Card) injection-site erythema, injection-site swelling, or injection-site pain/tenderness was assessed.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with data at the time of assessment.

The percentage of participants with solicited (Vaccine Report Card) injection-site erythema, injection-site swelling, and injection-site pain/tenderness was assessed.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with data at the time of assessment.

An adverse event (AE) is any untoward medical occurrence in a participant administered a pharmaceutical product and which does not necessarily have to have a causal relationship with this treatment. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding, for example), symptom, or disease temporally associated with the use of a medicinal product or protocol - specified procedure, whether or not considered related to the medicinal product or protocol - specified procedure. Any worsening (i.e., any clinically significant adverse change in frequency and/or intensity) of a preexisting condition that is temporally associated with the use of the Sponsor's product, is also an AE. The percentage of participants with one or more adverse events for Day 1 through Day 42 after vaccination 1 and Day 1 through Day 42 after vaccination 2 was reported.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with data at the time of assessment.

A serious adverse event (SAE) is defined as an adverse event that resulted in death, was life threatening, resulted in persistent or significant disability or incapacity, resulted in or prolonged a hospitalization, is a congenital anomaly or birth defect, is a cancer, was an overdose, or was an important medical event based on appropriate medical judgment. The percentage of participants with one or more SAEs ~180 days after vaccination 2 was reported.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with data at the time of assessment.

The percentage of participants with one or more vaccine-related adverse events for Day 1 through Day 42 after vaccination 1 and Day 1 through Day 42 after vaccination 2 was reported.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with data at the time of assessment.

All systemic adverse events were recorded on an electronic vaccination report card (eVRC) for Day 1 through Day 42 after vaccination 1. The percentage of participants with one or more systemic adverse events (incidence ≥4 participants in one or more of the vaccination groups) was reported.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with data at the time of assessment.

All systemic adverse events were recorded on an electronic vaccination report card (eVRC) for Day 1 through Day 42 after vaccination 2. The percentage of participants with one or more systemic adverse events was assessed. A specific adverse event was reported only if its incidence was >0% in one or more vaccination groups after rounding.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with data at the time of assessment.

The percentage of participants with seropositive antibody titer (≥1.25gpELISA units/mL) at baseline and postvaccination serology contributing to the per-protocol analysis was assessed. Confidence interval is calculated if there are at least 5 subjects who are seropositive. Antibody titers were assessed using gpELISA.

The analysis population consisted of all participants with seropositive antibody titer (≥1.25gpELISA units/mL) at baseline and with available postvaccination serology data.

Blood samples were taken at pre-vaccination (baseline) and approximately 43 days after vaccination 1 to determine the geometric mean titer (GMT) of VZV antibodies via gpELISA. The geometric mean fold rise (GMFR) was calculated as GMT post vaccination 1/GMT pre-vaccination (baseline). Confidence interval is calculated if there are at least 5 subjects who are seropositive.

The analysis population consisted of all participants with with seropositive antibody titer (≥1.25gpELISA units/mL) at baseline and with available postvaccination serology data.

The percentage of participants with a geometric mean ≥4-fold rise from baseline of ≥1.25gpELISA units/mL in VZV antibody titer at approximately 43 days after vaccination 1 was assessed.

The analysis population consisted of all participants with seropositive antibody titer (≥1.25gpELISA units/mL) and available postvaccination serology data.

The percentage of participants with one or more vaccine-related serious adverse events up to ~180 days after vaccination 2 was reported. The study investigator determines whether the serious adverse event is related to the vaccine.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with data at the time of assessment.

The percentage of participants discontinued from the study due to an adverse event for Day 1 through Day 42 after vaccination 1 and Day 1 through Day 42 after vaccination 2 was reported.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with data at the time of assessment.

The percentage of participants with unsolicited injection-site adverse events (or AEs not superficially listed on eVRC) for Day 1 through Day 42 after vaccination 1 was assessed. A specific adverse event was reported only if its incidence was >0% in one or more vaccination groups after rounding.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with data at the time of assessment.

The percentage of participants with unsolicited injection-site adverse events (or AEs not superficially listed on eVRC) for Day 1 through Day 42 after vaccination 2 was assessed. A specific adverse event was reported only if its incidence was >0% in one or more vaccination groups after rounding.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with data at the time of assessment.

The percentage of participants with medically-attended AEs up to ~180 days after vaccination 2 that did not meet the definition of serious adverse event (incidence ≥5% in one or more vaccination groups) was reported.

The analysis population consisted of all randomized/allocated participants who received at least 1 vaccination of study treatment with data at the time of assessment.