A Phase 3 interventional study of Investigational varicella vaccine and Marketed varicella vaccine in Chickenpox, sponsored by GlaxoSmithKline. Recruiting at 6 sites in 2 countries. Open to participants aged 12 Months to 15 Months, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-05-29.
Sponsored by GlaxoSmithKline · Phase 3, Interventional, and Prevention
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.
180 studies on the registry are indexed under Chickenpox; 28 are open to participants now.
This study's planned enrollment of 600 is above the median of 475 across 149 interventional studies indexed under Chickenpox.
Browse Chickenpox studies →GlaxoSmithKline is the lead sponsor of 3,650 studies on the registry; 118 are open to participants now.
Of its 264 completed or terminated interventional studies of FDA-regulated products, 241 (91%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
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 , 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.
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.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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: Marketed varicella vaccine · Biological: MMR vaccine · Biological: Hepatitis A vaccine · Biological: PCV (pneumococcal conjugate vaccine) 13 · Biological: PCV 20 · Biological: Vaxneuvance
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: Investigational varicella vaccine · Biological: MMR vaccine · Biological: Hepatitis A vaccine · Biological: PCV (pneumococcal conjugate vaccine) 13 · Biological: PCV 20 · Biological: Vaxneuvance
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: Investigational varicella vaccine · Biological: Marketed varicella vaccine · Biological: MMR vaccine · Biological: Hepatitis A vaccine · Biological: PCV (pneumococcal conjugate vaccine) 13 · Biological: PCV 20 · Biological: Vaxneuvance
Investigational varicella vaccine administered subcutaneously.
Marketed varicella vaccine administered subcutaneously.
MMR vaccine co-administered subcutaneously or intramuscularly.
Hepatitis A vaccine co-administered intramuscularly.
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.
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.
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.
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
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).
Time frame: 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
Concentrations of anti-VZV gE IgG are presented as GMC and expressed in mIU/mL for each group.
Time frame: At Day 133 (within 43 days post-dose 2)
Percentage of participants with seroresponse to anti-VZV gE IgG for VV-VNS group
Seroresponse is defined as post-vaccination (Day 43 post Dose 2) anti-VZV gE IgG concentration \>= 300 mIU/mL.
Time frame: At Day 133 (within 43 days post-dose 2)
GMC of anti-VZV gE IgG for VV-VNS group
Concentrations of anti-VZV gE IgG are presented as GMC and expressed in mIU/mL for each group.
Time frame: At Day 133 (within 43 days post-dose 2)
Percentage of participants reporting each solicited administration site event
Solicited administration site events include injection site redness, pain and swelling.
Time frame: Day 1 (post-dose 1) to Day 4
Percentage of participants reporting each solicited administration site event
Solicited administration site events include injection site redness, pain and swelling.
Time frame: Day 91 (post-dose 2) to Day 94
Percentage of participants reporting each solicited systemic event
Solicited systemic events include drowsiness, loss of appetite and irritability.
Time frame: Day 1 (post-dose 1) to Day 15
Percentage of participants reporting each solicited systemic event
Solicited systemic events include drowsiness, loss of appetite and irritability.
Time frame: Day 91 (post-dose 2) to Day 105
Percentage of participants reporting each solicited systemic event in terms of fever
Fever is defined as temperature \>=38.0 degrees Celsius (°C) by any route (the preferred location for measuring temperature is the axilla).
Time frame: Day 1 (post-dose 1) to Day 22
Percentage of participants reporting each solicited systemic event in terms of fever
Fever is defined as temperature \>=38.0 degrees °C by any route (the preferred location for measuring temperature is the axilla).
Time frame: Day 91 (post-dose 2) to Day 112
Percentage of participants reporting each solicited administration site event
Solicited administration site include injection site varicella-like rash.
Time frame: Day 1 (post-dose 1) to Day 43
Percentage of participants reporting each solicited administration site event
Solicited administration site include injection site varicella-like rash.
Time frame: Day 91 (post-dose 2) to Day 133
Percentage of participants reporting each solicited systemic event
Solicited systemic events includes varicella-like rash (non-injection site), and general rash (not varicella-like).
Time frame: Day 1 (post-dose 1) to Day 43
Percentage of participants reporting each solicited systemic event
Solicited systemic events includes varicella-like rash (non-injection site), and general rash (not varicella-like).
Time frame: Day 91 (post-dose 2) to Day 133
Percentage of participants reporting unsolicited adverse events (AEs)
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.
Time frame: Day 1 (post-dose 1) to Day 43
Percentage of participants reporting unsolicited adverse events (AEs)
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.
Time frame: Day 91 (post-dose 2) to Day 133
Percentage of participants reporting medically attended AEs (MAAE)
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.
Time frame: Day 1 (post-dose 1) to Day 271 (study end)
Percentage of participants reporting serious adverse events (SAEs)
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.
Time frame: Day 1 (post-dose 1) to Day 271 (study end)
Plan to share: Yes — 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
Supporting information: Study protocol, Statistical analysis plan, Informed consent form, Clinical study report
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.
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.
Data sharing details ↗ · www.gsk-studyregister.com
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