NCT06740630 · GlaxoSmithKline
A Study on the Immune Response and Safety of an Investigational Chickenpox Vaccine When Given to Healthy Children 12 to 15 Months of Age
What this study is about
The purpose of this study is to assess the consistency of immune response to three different lots of GSK's experimental varicella vaccine (VNS Vaccine), and to compare the safety and immune response of VNS vaccine to an already approved varicella vaccine (VV) known as Varivax.
View original scientific description
The purpose of this study is to assess the consistency of immune response to three different lots of GSK's investigational varicella vaccine (VNS Vaccine), and to compare the safety and immune response of VNS vaccine to an already approved varicella vaccine (VV) known as Varivax. The study will be conducted in healthy children aged 12 to 15 months, who have neither contracted varicella nor received a varicella vaccination.
Interventions
BIOLOGICAL
Investigational varicella vaccine_Lot 1
Investigational varicella vaccine of Lot 1 administered subcutaneously.
BIOLOGICAL
Investigational varicella vaccine_Lot 2
Investigational varicella vaccine of Lot 2 administered subcutaneously.
BIOLOGICAL
Investigational varicella vaccine_Lot 3
Investigational varicella vaccine of Lot 3 administered subcutaneously.
BIOLOGICAL
Marketed varicella vaccine_Lot 1
Marketed varicella vaccine of Lot 1 administered subcutaneously.
BIOLOGICAL
Marketed varicella vaccine_Lot 2
Marketed varicella vaccine of Lot 2 administered subcutaneously.
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.
Primary outcome measures
Percentage of participants with seroresponse to Varicella Zoster Virus (VZV) anti-glycoprotein E (gE) Immunoglobulin (IgG) for the 3 lots of VNS vaccine groups
Time frame: At Day 43
Seroresponse is defined as post-vaccination (Day 43) anti-VZV gE IgG antibody concentration greater than or equal to (\>=) 300 milli-international units per milliliter (mIU/mL) among participants who were seronegative \[(antibody concentration less than (\<) LLOQ (Lower limit of quantification)\] before vaccination. A seronegative participant is a participant whose antibody concentration is below the LLOQ of the assay. A seropositive participant is a participant whose antibody concentration is greater than or equal to the LLOQ of the assay.
Geometric Mean Concentration (GMC) of anti-VZV gE IgG for the 3 lots of VNS vaccine groups
Time frame: At Day 43
Concentrations of anti-VZV gE IgG presented as GMCs and expressed in mIU/mL for each group.
Percentage of participants with seroresponse to anti-VZV gE IgG for the 3 pooled lots of VNS vaccine groups compared with the 2 pooled lots of VV groups
Time frame: At Day 43
Seroresponse is defined as post-vaccination (Day 43) anti-VZV gE IgG concentration \>= 300 mIU/mL among participants who were seronegative (antibody concentration \< LLOQ) before vaccination. A seronegative participant is a participant whose antibody concentration is below the LLOQ of the assay. A seropositive participant is a participant whose antibody concentration is greater than or equal to the LLOQ of the assay.
GMCs of anti-VZV gE IgG for the 3 pooled lots of VNS vaccine groups compared with the 2 pooled lots of VV groups
Time frame: At Day 43
Concentrations of anti-VZV gE IgG are presented as GMCs and expressed in mIU/mL for each group.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Participant's parent(s) Legally acceptable representatives /(LAR\[s\]), who, in the opinion of the investigator, can and will comply with the requirements of the protocol (e.g., completion of the eDiaries, return for follow-up visits).
- 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 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
Where
- Mobile, Alabama
- Hot Springs, Arkansas
- Sherwood, Arkansas
- Canoga Park, California
- Covina, California
- Fullerton, California
- Long Beach, California
- Los Angeles, California
- Paramount, California
- Sacramento, California
- Ventura, California
- Walnut Creek, California
And 41 more locations — see the full list below.
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 29, 2026 · Source of record for eligibility and locations