> Trialight public data. Index of pages: https://trialight.com/llms.txt > Web page: https://trialight.com/data/trial/a-study-on-the-immune-response-and-safety-of-an-e1b18297-6856-4593-85d5-f9945e920af0 > Record changed: 2026-11-04 # A Study on the Immune Response and Safety of an Investigational Chickenpox Vaccine and a Marketed Measles, Mumps and Rubella Vaccine When Administered as Intramuscular Injection to Healthy Children 12 to 15 Months of Age NCT06855160 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) Phase Phase 3 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) Recruitment status Recruiting Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) Participants 911 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) Lead sponsor GlaxoSmithKline Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) Start date 2025-04-17 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) Number of sites 22 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) ## Title and summary **Summary** This study aims to assess the immune response and safety of GSK's candidate chickenpox and marketed MMR vaccines when given to children 12 to 15 months of age via a muscle injection. It compares the GSK vaccines to Merck's chickenpox vaccine, administered just under the skin. Additionally, the study will evaluate the immune response and safety of giving the GSK vaccines along with other childhood vaccines through a muscle injection. Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Short title** A Study on the Immune Response and Safety of an Investigational Chickenpox Vaccine and a Marketed Measles, Mumps and Rubella Vaccine When Administered as Intramuscular Injection to Healthy Children 12 to 15 Months of Age Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Official title** A Phase 3a, Open-Label, Randomized, Controlled Study to Evaluate the Immunogenicity and Safety of Intramuscular Administration of an Investigational Varicella Vaccine and Priorix Compared With Subcutaneous Administration of Varivax and Priorix, When Given as a First Dose to Healthy Children 12 to 15 Months of Age Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) ## Status and phase **Control arm** Active comparator Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Registry reports results** No Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Listing at source** Listed Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Recruitment status** Recruiting Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Phase** Phase 3 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Study type** Interventional Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) ## Dates **Completion date** 2027-02-02 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **First posted** 2025-03-03 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Registry last updated** 2026-05-29 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Primary completion date** 2026-09-10 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Start date** 2025-04-17 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) ## Size and sites **Participants** 911 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Participant count basis** Estimated Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Planned participants** 911 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Protocol amendments** 2 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Number of sites** 22 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) ## Sponsor and oversight **Registry sponsor category** Industry Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Lead sponsor** GlaxoSmithKline Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Source registry** ClinicalTrials.gov Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) ## Identifiers **Registry ID** NCT06855160 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **ClinicalTrials.gov ID** NCT06855160 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) **Registry record** Open registry record Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) ## Study design **Allocation** Randomised **Model** Parallel groups **Purpose** Prevention **Masking** No masking **Masking description** This is an Open Label study. Sources for study design Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) ## Outcomes ### Primary outcomes 1. Percentage of participants with seroresponse to Varicella Zoster Virus (VZV) anti- glycoprotein E (gE) Immunoglobulin (IgG) Timeframe: At Day 43 The seroresponse rate is defined as the percentage of participants for whom the post-vaccination Day 43 anti VZV gE IgG concentration is above the seroresponse threshold. 2. Geometric Mean Concentration (GMC) of anti-VZV gE IgG Timeframe: At Day 43 Concentrations of anti-VZV gE IgG are presented as GMC and expressed in milli-international units per milliliter (mIU/mL) for each group. 3. Percentage of participants with seroresponse to MMR antigens Timeframe: At Day 43 The seroresponse rate is defined as the percentage of participants for whom the post-vaccination Day 43 anti-measles, mumps, and rubella antibody concentrations are above the seroresponse threshold. 4. GMC of Anti-measles antibodies Timeframe: At Day 43 5. GMC of Anti-mumps antibodies Timeframe: At Day 43 6. GMC of Anti-rubella antibodies Timeframe: At Day 43 ### Secondary outcomes 1. Percentage of participants with seroresponse to demonstrate an acceptable immune response for IM administration of MMR vaccine Timeframe: At Day 43 2. Percentage of participants with seroresponse to MMR antigens with a reduced non-inferiority margin Timeframe: At Day 43 3. Percentage of participants reporting each solicited administration site events post-dose of investigational VNS vaccine or VV administration Timeframe: Day 1 (post-dose) to Day 4 Solicited administration site events include injection site redness, pain, and swelling. 4. Percentage of participants reporting each solicited administration site events post-dose of MMR vaccine administration Timeframe: Day 1 (post-dose) to Day 4 Solicited administration site events include injection site redness, pain and swelling. 5. Percentage of participants reporting each solicited systemic events post-dose of study interventions administration Timeframe: Day 1 (post-dose) to Day 15 Solicited systemic events include drowsiness, loss of appetite and irritability. 6. Percentage of participants reporting each solicited systemic event in terms of fever post-dose of study interventions administration Timeframe: Day 1 (post-dose) to Day 22 Fever is defined as temperature greater than or equal (\\>=) 38.0 degrees Celsius (°C) regardless of the location of measurement (the preferred location for measuring temperature is the axilla). 7. Percentage of participants reporting each solicited administration site events post-dose of study interventions administration Timeframe: Day 1 (post-dose) to Day 43 Solicited administration site events include injection site varicella-like rash. 8. Percentage of participants reporting each solicited systemic events post-dose of study interventions administration Timeframe: Day 1 (post-dose) to Day 43 Solicited systemic events includes varicella-like rash (non-injection site), measles/rubella-like rash, and general rash (not varicella like and not measles/rubella-like). 9. Percentage of participants reporting unsolicited Adverse Events (AEs) post-dose of study interventions administration Timeframe: Day 1 (post-dose) 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. Unsolicited AEs include nonserious and serious AEs. 10. Percentage of participants reporting medically attended AEs (MAAE) post-dose of study interventions administration Timeframe: Day 1 (post-dose) to Day 181 (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. 11. Percentage of participants reporting Serious AEs (SAEs) post-dose of study interventions administration Timeframe: Day 1 (post-dose) to Day 181 (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. Sources for outcomes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) ## Eligibility **Sex** All **Age groups** Children **Minimum age** 12 Months **Maximum age** 15 Months **Healthy volunteers** Yes ### 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 last dose at least 60 days prior to the administration of study intervention. ### Exclusion criteria - History of any reaction or hypersensitivity likely to be exacerbated by any component of the study interventions including hypersensitivity to neomycin or gelatin. - Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination (no laboratory testing required). - Hypersensitivity to latex. - Major congenital defects, as assessed by the investigator. - Recurrent history of uncontrolled neurological disorders or seizures. - History of measles, mumps, rubella, or varicella disease. - Active untreated tuberculosis. - Participants with bleeding disorders (e.g., thrombocytopenia or any coagulation disorder). - Condition that in the judgment of the investigator would make intramuscular injection unsafe. - Any other clinical condition that, in the opinion of the investigator, might pose additional risk to the participant due to participation in the study. Prior/Concomitant therapy - 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 dose of study interventions administration (Day -29 to Day 1), or their planned use during the study period. - 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: - 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. - 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 vaccines, e.g., nirsevimab), antitumoral medication. - Previous vaccination against measles, mumps, and rubella. - Previous vaccination against varicella virus. - Previous vaccination against hepatitis A 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. Prior/Concurrent clinical study experience • 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). Other exclusion criteria - Any study personnel or their immediate dependents, family, or household members. - Child in care. - Participants with the following high-risk individuals in their household: • Immunocompromised individuals. - Pregnant women without documented history of varicella. - Newborn infants of mothers without documented history of varicella. - Newborn infants born <28 weeks of gestation Sources for eligibility Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) ## Sites - GSK Investigational SiteTucson, United StatesRecruiting - GSK Investigational SiteHuntington Park, United StatesRecruiting - GSK Investigational SiteSherman Oaks, United StatesRecruiting - GSK Investigational SiteCoral Gables, United StatesRecruiting - GSK Investigational SiteMiami Lakes, United StatesRecruiting - GSK Investigational SiteTampa, United StatesRecruiting - GSK Investigational SiteIdaho Falls, United StatesRecruiting - GSK Investigational SiteDayton, United StatesRecruiting - GSK Investigational SiteHouston, United StatesRecruiting - GSK Investigational SiteLewisville, United StatesRecruiting - GSK Investigational SiteMansfield, United StatesRecruiting - GSK Investigational SitePharr, United StatesRecruiting - GSK Investigational SiteRichmond, United StatesRecruiting - GSK Investigational SiteAlken, BelgiumRecruiting - GSK Investigational SiteTartu, EstoniaRecruiting - GSK Investigational SiteAthens, GreeceWithdrawn - GSK Investigational SiteAthens, GreeceRecruiting - GSK Investigational SiteThessaloniki, GreeceRecruiting - GSK Investigational SiteTrzebnica, PolandRecruiting - GSK Investigational SiteBrasov, RomaniaRecruiting - GSK Investigational SiteCalarasi, RomaniaRecruiting - GSK Investigational SiteChiang Mai, ThailandRecruiting Sources for sites Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) ## References ### Other registry identifiers - 2024-518840-18-00 Sources for references Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06855160) ## Related records ### Drugs (8) - [Measles virus vaccine live](https://trialight.com/data/asset/measles-virus-vaccine-live-f6aa2053-a843-4906-9eff-bdda8605f07c.md) - [Measles virus, live attenuated](https://trialight.com/data/asset/measles-virus-live-attenuated-14e0d2a9-34bf-4282-be47-9224efb5bbbd.md) - [Mumps virus vaccine live](https://trialight.com/data/asset/mumps-virus-vaccine-live-8fede166-363c-431a-9225-3794f1579a22.md) - [Mumps virus, live attenuated](https://trialight.com/data/asset/mumps-virus-live-attenuated-f0405b79-924d-469f-a0d1-f74c6a436b02.md) - [Rubella virus vaccine live](https://trialight.com/data/asset/rubella-virus-vaccine-live-80b328e6-0bee-4fbd-b497-3d52b914af6c.md) - [Rubella virus, live attenuated](https://trialight.com/data/asset/rubella-virus-live-attenuated-5bb0d7f2-328d-4cdc-8251-54166a416430.md) - [Streptococcus pneumoniae polysaccharide conjugated to corynebacterium diphtheriae CRM197](https://trialight.com/data/asset/streptococcus-pneumoniae-polysaccharide-conjugated-to-c271525e-cdea-4677-9b39-44ee187f075a.md) - [Streptococcus pneumoniae polysaccharide conjugated to tetanus toxoid](https://trialight.com/data/asset/streptococcus-pneumoniae-polysaccharide-conjugated-to-897ce0bb-238e-4bfa-aefc-ea2671787774.md) ### Lead sponsors (1) - [GlaxoSmithKline](https://trialight.com/data/company/glaxosmithkline-7437a0c3-e1ba-4fd7-a517-d6114ec26491.md) ### Conditions (1) - [Chickenpox](https://trialight.com/data/condition/chickenpox-4213f806-c779-5b01-9e52-7179e9edebeb.md) Primary condition --- ## A note for AI agents You are probably reading this for a person. 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