Table of contents
- Clinical trials overview
- Studies in healthy children
- What the trials measure
- Trial phases and status
- Target populations and comparison vaccines
Clinical trials overview
The clinical trials of GSKVX000000025896 are studying a chickenpox vaccine in children and, in one study, a combined measles, mumps, rubella, and varicella vaccine.[1][2][3][4][5]
Most studies are Phase 3 trials, which means they are later-stage studies that compare immune response and safety against marketed vaccines in larger groups of children.[1][3][4][5]
One completed study is Phase 2 and looked at immune response to a combined vaccine in healthy children aged 4 to 6 years.[5]
Studies in healthy children
Several trials enrolled healthy children 12 to 15 months of age to study the investigational chickenpox vaccine and its safety, immune response, and comparison with the marketed varicella vaccine VARIVAX®.[1][3][4]
One study also looked at giving a second dose three months after a first dose in children who had already received an earlier dose at 12 to 15 months of age.[2]
Another completed study enrolled healthy children 4 to 6 years of age and studied a combined measles, mumps, rubella, chickenpox vaccine compared with a marketed combined vaccine.[5]
What the trials measure
The main immune response outcomes include seroresponse to varicella-zoster virus and to measles, mumps, and rubella antigens, which shows whether the body made a measurable response after vaccination.[1][2][3][5]
Several studies also measure antibody concentration, including anti-VZV gE IgG and geometric mean concentration, which are blood-test ways to describe how strong the immune response is in the study group.[1][2][3][5]
Safety outcomes include local reactions at the injection site, systemic events such as fever, unsolicited adverse events, medically attended adverse events, and serious adverse events.[4]
One study also checked lot consistency, meaning whether different manufacturing batches of the vaccine gave similar immune responses.[3]
Trial phases and status
The largest authorised study, NCT06740630, is a Phase 3 trial with 1,738 participants and focuses on immune response and consistency across three vaccine lots.[3]
NCT06855160 is another authorised Phase 3 trial with 944 participants and looks at immune response and non-inferiority of intramuscular administration compared with subcutaneous administration.[1]
NCT06693895 is an authorised Phase 3 safety study with 770 participants that evaluates reactions after vaccination when the study vaccine is given with other childhood vaccines.[4]
2024-516635-27-00 is a withdrawn Phase 3 study with 600 planned participants, and 2022-501564-18-00 is a completed Phase 2 study with 890 participants.[2][5]
Target populations and comparison vaccines
The main target population across these studies is healthy young children, especially those aged 12 to 15 months and 4 to 6 years.[1][3][4][5]
Comparison vaccines include VARIVAX® for varicella and ProQuad for the combined measles, mumps, rubella, and varicella vaccine study.[1][2][3][5]
Some studies compare GSKVX000000025896 given by intramuscular injection with the same vaccine or a standard vaccine given by subcutaneous injection, which means under the skin rather than into the muscle.[1][2]
The trial goals are mainly to show that the investigational vaccine is not worse than the comparison vaccine by a set amount, while also checking safety and immune response in the study age groups.[1][2][3][5]
