A Study on the Immune Response and Safety of the Second Dose of an Investigational Chickenpox Vaccine When Given to Healthy Children 3 Months After a First Dose at 12 to 15 Months of Age

May 27, 2026 updated by: GlaxoSmithKline

A Phase 3a, Observer-blind, Randomized, Controlled, Study to Evaluate the Immunogenicity and Safety of an Investigational Varicella Vaccine Compared With Varivax, When Given as a Second Dose to Healthy Children, 3 Months After the Administration of a First Dose at 12 to 15 Months of Age

The purpose of this study is to evaluate the immune response and safety of GSKs investigational varicella vaccine (VNS Vaccine) compared to an already approved varicella vaccine, Varivax (VV), when administered as second dose to healthy children. 3 months after first dose at 12 to 15 months. The study will be conducted in children who have not previously contracted varicella or received a varicella vaccination.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

600

Phase

  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

  • Dominican Republic
      • Constanza, Dominican Republic, 11201
        • Recruiting
        • GSK Investigational Site
        • Contact:
        • Contact:
        • Principal Investigator:
          • Demian Arturo Herrera Morban
      • Santo Domingo Oeste, Dominican Republic, 11906
        • Recruiting
        • GSK Investigational Site
        • Contact:
        • Contact:
        • Principal Investigator:
          • Luis Martinez
    • La Altagracia Province
      • Salvaleón de Higüey, La Altagracia Province, Dominican Republic, 23000
        • Recruiting
        • GSK Investigational Site
        • Contact:
        • Contact:
        • Principal Investigator:
          • Fior Stephane Severino Medina
  • Honduras
      • San Pedro Sula, Honduras, 21104
        • Recruiting
        • GSK Investigational Site
        • Contact:
        • Contact:
        • Principal Investigator:
          • Agustin Bueso
      • Tegucigalpa, Honduras, 11101
        • Recruiting
        • GSK Investigational Site
        • Contact:
        • Contact:
        • Principal Investigator:
          • Bessy Italia Turcios Gomez
      • Tegucigalpa, Honduras, 2449
        • Recruiting
        • GSK Investigational Site
        • Contact:
        • Contact:
        • Principal Investigator:
          • Pamela Zacasa Vargas

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Participant's parent(s)/Legally acceptable representative (LAR)(s), who, in the opinion of the investigator, can and will comply with the requirements of the protocol
  • Written or witnessed/thumb printed informed consent obtained from the participant's parent(s)/LAR(s) prior to performance of any study-specific procedure.
  • Healthy participants as established by medical history and clinical examination before entering into the study.
  • A male or female between, and including, 12 to 15 months of age (i.e., from the day of 1 year birthday until the day before 16 months of age) at the time of the administration of the first study interventions.
  • Only for children in countries where PCV is recommended at 12 to 15 months of age as per national immunization schedule and provided as part of the study interventions: participant who previously received the primary series of PCV in the first year of life with last dose at least 60 days prior to study entry.

Exclusion Criteria:

  • History of any reaction or hypersensitivity likely to be exacerbated by any component of the study interventions.
  • Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination.
  • Hypersensitivity to latex.
  • Major congenital defects, as assessed by the investigator.
  • Recurrent history of uncontrolled neurological disorders or seizures.
  • History of varicella disease.
  • Active untreated tuberculosis.
  • Any other clinical condition that, in the opinion of the investigator, might pose additional risk to the participant due to participation in the study.
  • Use of any investigational or non-registered product (drug, vaccine or invasive medical device) other than the study interventions during the period beginning 30 days before the first dose of study interventions (Day -29 to Day 1), or their planned use during the study period.
  • Planned administration of a vaccine in the period starting 30 days before the first dose and ending 43 days after the second dose of study interventions administration (Visit 3), with the exception of inactivated influenza vaccine which may be given at any time during the study and administered at a different location than the study interventions.

  • Chronic administration of immune-modifying drugs (defined as more than 14 consecutive days in total) and/or planned use of long-acting immune-modifying treatments at any time up to the end of the study.

    • Up to 90 days prior to the study intervention administration:

      i) For corticosteroids, this will mean prednisone equivalent >=0.5 mg/kg/day with maximum of 20 mg/day for pediatric participants. Inhaled and topical steroids are allowed.

ii) Administration of immunoglobulins and/or any blood products or plasma derivatives.

  • Up to 180 days prior to study interventions administration: long acting immune-modifying drugs including among others immunotherapy (e.g., tumor necrosis factor-inhibitors), monoclonal antibodies (except the ones not interfering with the immune response to the study vaccinese.g., nirsevimab), antitumoral medication.
  • Previous vaccination against measles, mumps, and rubella.
  • Previous vaccination against hepatitis A virus.
  • Previous vaccination against varicella virus.
  • Only for children in countries where PCV is recommended at 12 to 15 months of age as per national immunization schedule and provided as part of the study interventions, participant who previously received a booster dose of any PCV.
  • Concurrently participating in another clinical study, at any time during the study period, in which the participant has been or will be exposed to an investigational or a non-investigational intervention (drug/invasive medical device).
  • Child in care.
  • Any study personnel's immediate dependents, family, or household members.

  • Participants with the following high-risk individuals in their household:

    i) Immunocompromised individuals. ii) Pregnant women without documented history of varicella. iii) Newborn infants of mothers without documented history of varicella. iv) Newborn infants born less than (<) 28 weeks of gestation.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: VV-VV Group
Participants receive 2 doses of a VV vaccine on Day 1 and Day 91. 1 dose of measles, mumps, and rubella (MMR) vaccine, 1 dose of hepatitis A vaccine (HAV), and 1 dose of PCV (either PCV 13 or Vaxneuvance or PCV 20) on Day 1. A second dose of MMR vaccine will be co-administered to the participants in countries where a second dose of MMR is recommended at 15 to 18 months of age, as per national immunization schedule.
Biological: MMR vaccine
MMR vaccine co-administered subcutaneously or intramuscularly.
Biological: Hepatitis A vaccine
Hepatitis A vaccine co-administered intramuscularly.
Biological: PCV (pneumococcal conjugate vaccine) 13
The 13-valent pneumococcal conjugate vaccine co-administered intramuscularly. In some countries PCV will only be administered depending on the availability, country's registration status and national recommendations for pneumococcal vaccination at the time of study conduct.
Biological: PCV 20
The 20-valent pneumococcal conjugate vaccine co-administered intramuscularly. In some countries PCV will only be administered depending on the availability, country's registration status and national recommendations for pneumococcal vaccination at the time of study conduct.
Biological: Marketed varicella vaccine
Marketed varicella vaccine administered subcutaneously.
Biological: Vaxneuvance
The Vaxneuvance (15-valent pneumococcal conjugate vaccine co-administered intramuscularly. In some countries PCV will only be administered depending on the availability, country's registration status and national recommendations for pneumococcal vaccination at the time of study conduct.
Experimental: VNS-VNS Group
Participants receive 2 doses of a VNS vaccine on Day 1 and Day 91. 1 doses of MMR vaccine, 1 dose of HAV vaccine, and 1 dose of PCV (either PCV 13, Vaxneuvance or PCV 20) on Day 1. A second dose of MMR vaccine will be co-administered to the participants in countries where second dose of MMR is recommended at 15 to 18 months of age, as per national immunization schedule.
Biological: MMR vaccine
MMR vaccine co-administered subcutaneously or intramuscularly.
Biological: Hepatitis A vaccine
Hepatitis A vaccine co-administered intramuscularly.
Biological: PCV (pneumococcal conjugate vaccine) 13
The 13-valent pneumococcal conjugate vaccine co-administered intramuscularly. In some countries PCV will only be administered depending on the availability, country's registration status and national recommendations for pneumococcal vaccination at the time of study conduct.
Biological: PCV 20
The 20-valent pneumococcal conjugate vaccine co-administered intramuscularly. In some countries PCV will only be administered depending on the availability, country's registration status and national recommendations for pneumococcal vaccination at the time of study conduct.
Biological: Vaxneuvance
The Vaxneuvance (15-valent pneumococcal conjugate vaccine co-administered intramuscularly. In some countries PCV will only be administered depending on the availability, country's registration status and national recommendations for pneumococcal vaccination at the time of study conduct.
Biological: Investigational varicella vaccine
Investigational varicella vaccine administered subcutaneously.
Experimental: VV-VNS Group
Participants receive 1 dose of VV vaccine on Day 1, 1 dose of VNS Vaccine on Day 91. 1 doses of MMR vaccine, 1 dose of HAV, and 1 dose of PCV (either PCV 13, Vaxneuvance or PCV 20) on Day 1. A second dose of MMR vaccine will be co-administered to the participants in countries where second dose of MMR is recommended at 15 to 18 months of age, as per national immunization schedule.
Biological: MMR vaccine
MMR vaccine co-administered subcutaneously or intramuscularly.
Biological: Hepatitis A vaccine
Hepatitis A vaccine co-administered intramuscularly.
Biological: PCV (pneumococcal conjugate vaccine) 13
The 13-valent pneumococcal conjugate vaccine co-administered intramuscularly. In some countries PCV will only be administered depending on the availability, country's registration status and national recommendations for pneumococcal vaccination at the time of study conduct.
Biological: PCV 20
The 20-valent pneumococcal conjugate vaccine co-administered intramuscularly. In some countries PCV will only be administered depending on the availability, country's registration status and national recommendations for pneumococcal vaccination at the time of study conduct.
Biological: Marketed varicella vaccine
Marketed varicella vaccine administered subcutaneously.
Biological: Vaxneuvance
The Vaxneuvance (15-valent pneumococcal conjugate vaccine co-administered intramuscularly. In some countries PCV will only be administered depending on the availability, country's registration status and national recommendations for pneumococcal vaccination at the time of study conduct.
Biological: Investigational varicella vaccine
Investigational varicella vaccine administered subcutaneously.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Percentage of participants with seroresponse to Varicella Zoster Virus (VZV) anti- glycoprotein E (gE) IgG for 2 doses of VNS vaccine compared to 2 doses of VV
Time Frame: At Day 133 (43 days post-dose 2)
Seroresponse is defined as post-vaccination (Day 43 post Dose 2) anti VZV gE Immunoglobulin (IgG) concentration greater than equal to (>=) 300 milli-international units per milliliter (mIU/mL).
At Day 133 (43 days post-dose 2)
Geometric Mean Concentration (GMC) of anti-VZV gE IgG for 2 doses of VNS vaccine compared to 2 doses of VV
Time Frame: At Day 133 (within 43 days post-dose 2)
Concentrations of anti-VZV gE IgG are presented as GMC and expressed in mIU/mL for each group.
At Day 133 (within 43 days post-dose 2)

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Percentage of participants with seroresponse to anti-VZV gE IgG for VV-VNS group
Time Frame: At Day 133 (within 43 days post-dose 2)
Seroresponse is defined as post-vaccination (Day 43 post Dose 2) anti-VZV gE IgG concentration >= 300 mIU/mL.
At Day 133 (within 43 days post-dose 2)
GMC of anti-VZV gE IgG for VV-VNS group
Time Frame: At Day 133 (within 43 days post-dose 2)
Concentrations of anti-VZV gE IgG are presented as GMC and expressed in mIU/mL for each group.
At Day 133 (within 43 days post-dose 2)
Percentage of participants reporting each solicited administration site event
Time Frame: Day 1 (post-dose 1) to Day 4
Solicited administration site events include injection site redness, pain and swelling.
Day 1 (post-dose 1) to Day 4
Percentage of participants reporting each solicited administration site event
Time Frame: Day 91 (post-dose 2) to Day 94
Solicited administration site events include injection site redness, pain and swelling.
Day 91 (post-dose 2) to Day 94
Percentage of participants reporting each solicited systemic event
Time Frame: Day 1 (post-dose 1) to Day 15
Solicited systemic events include drowsiness, loss of appetite and irritability.
Day 1 (post-dose 1) to Day 15
Percentage of participants reporting each solicited systemic event
Time Frame: Day 91 (post-dose 2) to Day 105
Solicited systemic events include drowsiness, loss of appetite and irritability.
Day 91 (post-dose 2) to Day 105
Percentage of participants reporting each solicited systemic event in terms of fever
Time Frame: Day 1 (post-dose 1) to Day 22
Fever is defined as temperature >=38.0 degrees Celsius (°C) by any route (the preferred location for measuring temperature is the axilla).
Day 1 (post-dose 1) to Day 22
Percentage of participants reporting each solicited systemic event in terms of fever
Time Frame: Day 91 (post-dose 2) to Day 112
Fever is defined as temperature >=38.0 degrees °C by any route (the preferred location for measuring temperature is the axilla).
Day 91 (post-dose 2) to Day 112
Percentage of participants reporting each solicited administration site event
Time Frame: Day 1 (post-dose 1) to Day 43
Solicited administration site include injection site varicella-like rash.
Day 1 (post-dose 1) to Day 43
Percentage of participants reporting each solicited administration site event
Time Frame: Day 91 (post-dose 2) to Day 133
Solicited administration site include injection site varicella-like rash.
Day 91 (post-dose 2) to Day 133
Percentage of participants reporting each solicited systemic event
Time Frame: Day 1 (post-dose 1) to Day 43
Solicited systemic events includes varicella-like rash (non-injection site), and general rash (not varicella-like).
Day 1 (post-dose 1) to Day 43
Percentage of participants reporting each solicited systemic event
Time Frame: Day 91 (post-dose 2) to Day 133
Solicited systemic events includes varicella-like rash (non-injection site), and general rash (not varicella-like).
Day 91 (post-dose 2) to Day 133
Percentage of participants reporting unsolicited adverse events (AEs)
Time Frame: Day 1 (post-dose 1) to Day 43
Unsolicited AEs include any AE reported in addition to solicited events during the study, or any "solicited" symptoms with onset outside of the specified period of follow-up for solicited symptoms, are assessed for each group after the administration of all vaccines.
Day 1 (post-dose 1) to Day 43
Percentage of participants reporting unsolicited adverse events (AEs)
Time Frame: Day 91 (post-dose 2) to Day 133
Unsolicited AEs include any AE reported in addition to solicited events during the study, or any "solicited" symptoms with onset outside of the specified period of follow-up for solicited symptoms, are assessed for each group after the administration of all vaccines.
Day 91 (post-dose 2) to Day 133
Percentage of participants reporting medically attended AEs (MAAE)
Time Frame: Day 1 (post-dose 1) to Day 271 (study end)
A MAAE is an AE for which the participant received medical attention including any symptom or illness requiring hospitalization, or an emergency room visit, or visit to/by a healthcare professional.
Day 1 (post-dose 1) to Day 271 (study end)
Percentage of participants reporting serious adverse events (SAEs)
Time Frame: Day 1 (post-dose 1) to Day 271 (study end)
A SAE is an AE which results in death, is life-threatening, requires inpatient hospitalization or prolongation of existing hospitalization, results in disability/incapacity, or other situations that are considered serious per medical or scientific judgment.
Day 1 (post-dose 1) to Day 271 (study end)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

GlaxoSmithKline

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

May 15, 2025

Primary Completion (Estimated)

December 14, 2026

Study Completion (Estimated)

May 3, 2027

Study Registration Dates

First Submitted

January 31, 2025

First Submitted That Met QC Criteria

January 31, 2025

First Posted (Actual)

February 3, 2025

Study Record Updates

Last Update Posted (Actual)

May 29, 2026

Last Update Submitted That Met QC Criteria

May 27, 2026

Last Verified

May 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 214002
  • 2024-516635-27-00 (Other Identifier: EU CT Number)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

Study Sponsor will assess requests from qualified researchers for anonymized individual patient-level data and related study documents. Data sharing is subject to certain criteria, conditions, and exceptions. For further information, refer to https://www.gsk-studyregister.com/About_GSK_Patient_Level_Data_Sharing_Final_13July2023.pdf

IPD Sharing Time Frame

Anonymized IPD will be made available within 6 months of publication of primary, key secondary and safety results for studies in product with approved indication(s) or asset(s) with development terminated across all indications.

IPD Sharing Access Criteria

Anonymized IPD is shared with researchers whose proposals are approved by an Independent Review Panel and after a Data Sharing Agreement is in place. Access is provided for an initial period of 12 months, but an extension may be granted, when justified, for up to 6 months.

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • SAP
  • ICF
  • CSR

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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